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Long Life Dairy, Food and Beverage Products
White Paper
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Long Life Dairy, Food and Beverage Products
Table of Contents
Executive Summary . . . . . . . . . . . . . . . . . . .3
Introduction to SPX FLOW . . . . . . . . . . . .3Vision and commitment . . . . . . . . . . . . . . . . . . . . . . . . 3
Customer focus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Introduction to long life dairy, food and beverage products . . . . . . . . . . . . . . . . . . .4
Microbiology . . . . . . . . . . . . . . . . . . . . . . . .5Bacteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Spores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Enzymes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Moulds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Yeast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Bacteriophages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Toxicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Process classification . . . . . . . . . . . . . . . . .7Pasteurisation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Extended shelf life . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
UHT treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Sterilisation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
EU classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Process evaluation . . . . . . . . . . . . . . . . . .10The logarithmic reduction of spores and
sterilising efficiency . . . . . . . . . . . . . . . . . . . . . . . . . .10
Terms and expressions to characterise heat
treatment processes . . . . . . . . . . . . . . . . . . . . . . . . .10
Residence time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Commercial sterility . . . . . . . . . . . . . . . . . . . . . . . . . .12
Chemical and bacteriological changes at
high temperatures . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Raw material quality . . . . . . . . . . . . . . . . . . . . . . . . . .12
Shelf life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Choosing the right process . . . . . . . . . . 13The heat treatment processes . . . . . . . . . . . . . . . . .14
Plate heat exchangers . . . . . . . . . . . . . . . . . . . . . . . .14
Tubular heat exchangers . . . . . . . . . . . . . . . . . . . . . .15
Corrugated tubular heat exchangers . . . . . . . . . . . .15
Steam injection nozzles . . . . . . . . . . . . . . . . . . . . . . .16
Steam infusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Scraped surface heat exchangers . . . . . . . . . . . . . .17
Various aseptic UHT systems . . . . . . . . 17Indirect Plate Steriliser . . . . . . . . . . . . . . . . . . . . . . . .17
Indirect Tubular Steriliser . . . . . . . . . . . . . . . . . . . . . .19
Steam Infusion Steriliser . . . . . . . . . . . . . . . . . . . . . .20
High Heat Infusion Steriliser . . . . . . . . . . . . . . . . . . .21
Instant Infusion Pasteuriser . . . . . . . . . . . . . . . . . . . .22
Steam Injection Steriliser . . . . . . . . . . . . . . . . . . . . . .23
Scraped Surface Heat Exchanger Steriliser . . . . . .24
Pilot UHT Plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Sterile Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Deaerator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Extended shelf life/ESL . . . . . . . . . . . . . 26The Pure-LacTM process . . . . . . . . . . . . . . . . . . . . . .26
Comparison between different systems . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Process controls . . . . . . . . . . . . . . . . . . . 27
Filling and packaging . . . . . . . . . . . . . . . 29
Product development . . . . . . . . . . . . . . . 29
About SPX FLOW . . . . . . . . . . . . . . . . . 30
Contact us . . . . . . . . . . . . . . . . . . . . . . . . 31
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Long Life Dairy, Food and Beverage Products
There are a number of important microbiological factors that
need to be addressed in the production of long life dairy, food
and beverage products. The presence of microorganisms in the
milk must be reduced to a safe number in order to ensure suf-
ficient shelf life under appropriate storage conditions.
This can be achieved by a variety of thermal processes. The effi-
ciency of these processes is a factor of temperature and holding
time and can, if not properly controlled, lead to adverse effects
on flavour and appearance.
A number of systems of relevance to the dairy, food and bever-
age industries are discussed and advice is offered on how to
achieve the best quality product at a reasonable cost, taking into
account safe and trouble-free operation.
Efficient aseptic processing is an important factor in develop-
ment of new products. The SPX FLOW Innovation Centre in
Denmark offers Pilot Plant Testing and application solution
guidance services to help customers maximise the performance
of their plant. Pilot Testing can also be conducted on customers’
own premises based on rental equipment and, if required, with
support from SPX FLOW experts.
VI S ION AN D COM M ITM E NT
SPX FLOW designs, manufactures and markets process engi-
neering and automation solutions to the dairy, food, beverage,
marine, pharmaceutical and personal care industries through its
global operations.
We are committed to helping our customers all over the world to
improve the performance and profitability of their manufacturing
plant and processes. We achieve this by offering a wide range of
products and solutions from engineered components to design
of complete process plants supported by world-leading applica-
tions and development expertise.
We continue to help our customers optimise the performance
and profitability of their plant throughout its service life with
support services tailored to their individual needs through a
coordinated customer service and spare parts network.
CUSTOM E R FOCUS
Founded in 1910, APV, an SPX FLOW Brand, has pioneered
groundbreaking technologies over more than a century, setting
the standards of the modern processing industry.
Continuous research and development based on customer
needs and an ability to visualise future process requirements
drives continued mutual growth.
Executive Summary Introduction to SPX FLOW
SPX FLOW Innovation Centre, Silkeborg, Denmark
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Long Life Dairy, Food and Beverage Products
As one of the most complete food products of all, dairy products
are very important in human nutrition. However, dairy products are
also highly perishable and would easily lose their nutritional value,
flavour and appearance if protective measures were not taken.
Consequently, the dairy industry is one of the most advanced
industries in the food processing area, taking care of the milk
from when it leaves the udder of the cow – through transporta-
tion to the dairy, processing, packaging, and distribution – until it
reaches the consumer.
The technology of producing long-life products is today applied
throughout the food and beverage industries and in many cases
the processing plants are designed for multipurpose operation.
When aseptic technology was introduced more than 50 years
ago, it revolutionised the food industry by making it possible to
distribute high quality food products over long distances in a
cost-effective way.
The heart of aseptic technology for production of long-life dairy
products is aseptic processing, and since its introduction this
concept has been developed and refined to a point where any
need in respect of capacity, product viscosity, particulate content,
acidity or sensitivity to heat treatment can be met while securing
high quality, long-life products.
SPX FLOW was one of the pioneers in aseptic processing and
over the years we have developed a wide range of processing
concepts to satisfy all the needs of the industry.
In this publication, we will first discuss some of the micro-biolog-
ical factors, which must be considered in all aseptic processing,
together with the heating processes most commonly used for
reducing micro-organisms in dairy products: pasteurisation, steri-
lisation and ultra high temperature (UHT) treatment.
So-called commercial sterility is the aim of all UHT processes,
and the extent to which this is achieved in a particular process
can be measured, notably by reference to the bacteriological ef-
fect (B*) and the chemical effect (C*) of such processes. These
factors are explained in the section “Process Evaluation”.
The main part of the publication is devoted to an analysis of the
processing systems of most interest to the dairy, food and bev-
erage industry: Indirect Plate Steriliser, Indirect Tubular Steriliser,
Steam Infusion Steriliser, High Heat Infusion Steriliser, Instant
Infusion Pasteuriser, Steam Injection Steriliser and Indirect
Scraped Surface Heat Exchanger (SSHE) Steriliser.
In each case we describe the system, discuss its advantages
and limitations, and list a number of products for which the
system in question is particularly suitable (See Table 1 on page
5 and table 4 on page 28).
The Pilot UHT Plant is able to combine most of the aseptic pro-
cesses in one unit, which provides an efficient tool for pilot trials
and product development.
In aseptic processing, special consideration must be given to
some of the auxiliary equipment required. Aseptic tanks are not
a necessary requirement but often serve as a useful buffer for
sterilised products.
The area of extended shelf life products is becoming increas-
ingly important, and the development of the Pure-LacTM concept
is offering the industry and the consumers new solutions and
exciting opportunities.
With the large number of options available it becomes important
to be able to choose the solution, which provides the best quality
product at a reasonable cost, giving safe and trouble-free opera-
tion. A separate section has been made to cover this subject.
The process control system is not only necessary, it must incor-
porate up-to-date technology – not least on the software side.
Special attention must be given to the subsequent filling and
packaging of aseptically processed products.
Finally, we address the area of product development. SPX
FLOWs world wide capabilities in respect of product testing
makes it possible to work closely with customers in their efforts
to upgrade production and launch new products.
This publication is purely dealing with the indirect and direct
heat transfer processes.
SPX FLOW is also manufacturing various types of electrical – or
“electroheat” thermal processing equipment. This is dealt with in
a separate publication.
Introduction to long life dairy, food and beverage products
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Long Life Dairy, Food and Beverage Products
The key to production of long-life products with aseptic technol-
ogy is a detailed understanding of the microbiology of food.
Using the example of the dairy industry, the milk in the udder
of a healthy cow is free from bacteria, but as soon as the milk
comes into contact with the air it becomes contaminated with
micro-organisms.
If the temperature is favourable, the micro-organisms multiply
and very soon the milk will turn sour (or putrefy), developing an
unpleasant flavour. To prevent this from happening, the raw milk
is sub jected to heat treatment.
The term aseptic is usually defined as “free from or keeping
away” disease producing or putrefying microorganisms. In the
food industry the terms aseptic, sterile and commercially sterile
are often used interchangeably. This is not strictly correct. Sterili-
sation means 100% destruction of all living organisms, including
their spores, and this is very difficult to achieve.
Commercial sterility means that the product is free from mi-
croorganisms, which grow and consequently contribute to the
deterioration of the product. Microorganisms are extremely small
and can only be seen under a microscope. However, hundreds
or thousands of individual cells or groups of cells can form colo-
nies, which are visible to the naked eye, and some colonies have
colours, shapes, textures or odours, which make the organism
identifiable.
BACTE R IA
The term bacteria strictly means rod-shaped microorganisms
only, but is also used in a loose sense to include all micro-organ-
isms except yeast and moulds. The individual bacterium varies in
size from 0.5 to 3 micron.
The groups of bacteria, which are most important in the dairy
industry are the lactic acid, coliform, butyric acid, and putrefac-
tion bacteria. The bacterial count in milk coming from the farm
varies from a few thousands bacteria/ml for high quality milk
to several millions if the standard of cleaning, disinfection and
chilling is poor.
For milk to be classified as top quality, the CFU (Colony Forming
Units) should be less than 100,000/ml.
Bacteria are single-celled organisms, which normally multiply by
binary fission, i.e. splitting in two. The simplest and most com-
mon way to classify bacteria is according to their appearance
and shape. However, in order to be able to see bacteria, they
must first be stained and then studied under a microscope at a
magnification of approximately 1,000 X.
Microbiology
Table 1: A variety of dairy, food and beverage products and their suitability for treatment in thermal heat processing systems.
DAI RY, FOOD & B EVE RAG E PROD UCTS
PL
AT
E S
TE
RIL
ISE
R
TU
BU
LA
R S
TE
RIL
ISE
R
ST
EA
M I
NF
US
ION
S
TE
RIL
ISE
R
HIG
H H
EA
T I
NF
US
ION
S
TE
RIL
ISE
R
INS
TAN
T I
NF
US
ION
P
AS
TE
UR
ISE
R
ST
EA
M I
NJE
CT
ION
S
TE
RIL
ISE
R
SC
RA
PE
D S
UR
FA
CE
HE
AT
EX
CH
AN
GE
R S
YS
TE
MS
M I LK X X X X X
M I LK (F LAVO U R E D) X X X X X
M I LK (EVAP O RATE D) X X X X
M I LK (C O N C E NTRATE D) X X X X X
M I LK (S HAK E M I X) X X X X X
C R EAM X X X X X
C R EAM (WH I P P I N G) X X X X
C R EAM (SYNTH ETI C) X X X X X
YO G H U RT X X X X
YO G H U RT (D R I N K I N G) X X
YO G H U RT (F R U IT) X X
Q UAR K P R O D U CTS X
S OYA M I LK X X X X X
BABY FO O D X X X X
I C E C R EAM M I X X X X X X
C H E E S E D I P S X X X X
P R O C E S S E D C H E E S E X X X
D E S E RTS / P U D D I N G S X X X X
WH EY P R OTE I N C O N C . X X
C O F F E E WH ITE N E R X X X X X X X
E G G-BAS E D P R O D U CTS X
SAU C E X X X
S O U P S X X
C O F F E E / I C E TEA X X
F R U IT J U I C E X X
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Long Life Dairy, Food and Beverage Products
Based on a method of staining, developed by the Danish bacte-
riologist Gram, bacteria are divided into Gram negative (red) and
Gram positive (blue). The three characteristic shapes of bacteria
are spherical, rod-shaped and spiral. Diplococci arrange them-
selves in pairs, staphylococci form clusters, while streptococci
form chains.
Another way of classification is according to temperature prefer-
ence:
• Psychrotrophic bacteria (cold-tolerant) reproduce at
temperatures of 7°C or below.
• Psychrophilic bacteria (cold-loving) have an optimum growth
temperature below 20°C.
• Mesophilic bacteria ( loving the middle range) have optimum
growth temperatures between 20°C and 44°C.
• Thermophilic bacteria (heat-loving) have their optimum growth
temperatures between 45°C and 60°C.
• Thermoduric bacteria (heat-enduring) can tolerate high
temperatures – above 70°C. They do not grow and reproduce
at high temperatures, but can resist them without being killed.
Bacteria can only develop within certain temperature limits,
which vary from one species to another. Temperatures below
the minimum cause growth to stop, but do not kill the bacteria.
They are, however, damaged by repeated freezing and thawing.
If the temperature is raised above the maximum, the bacteria are
soon killed by heat. Most cells die within a few seconds of being
exposed to 70°C, but some bacteria can survive heating to 85°C
for 15 minutes, even though they do not form spores.
A third way of classifying micro-organisms is by their oxygen
requirement. The availability of oxygen is vital to the metabo-
lism of all organisms. Some bacteria consume oxygen from
the atmosphere; they are called aerobic bacteria. However, to
some bacteria free oxygen is a poison; they are called anaero-
bic bacteria and obtain the oxygen they need from chemical
compounds in their food supply. Some bacteria consume free
oxygen if it is present, but they can also grow in the absence of
oxygen; they are called facultatively anaerobic.
The acidity of the nutrient substrate for bacteria is also im-
portant. Sensitivity to pH changes varies from one species to
another, but most bacteria prefer a growth environment with
a pH around 7. Furthermore the salt and/or sugar concentra-
tion of a substrate has an important influence on the growth
of bacteria. The higher the concentration, the more growth
is inhibited. This is caused by the high osmotic pressure,
which will draw water out from the cell, thereby dehydrating it.
Osmotic pressure is used as a means of food preservation in
sweetened condensed milk, salted fish and fruit preserves like
jam and marmalade.
S POR E S
The spore is a form of protection against adverse conditions, e.g.
heat and cold, lack of moisture, lack of nutrients, or presence of
disinfectants. Only a few bacteria are spore forming e.g. Bacillus
and Clostridium. The spores germinate back into a vegetative
cell and start reproduction when conditions become favourable
again. The spores have no metabolism and can survive for years
in dry air and are much more resistant to adverse conditions
than bacteria. This includes heat treatment and it takes typically
20 minutes at 120°C to kill them with 100 percent certainty.
The UHT time/temperature combination reduces the number of
bacteria spores by a minimum of log 9, leaving very few bacteria
spores in UHT treated products.
E N ZYM E S
When the milk leaves the udder it contains enzymes, the so-
called original enzymes. Enzymes are also produced by the
bacteria in the milk,
the so-called bacterial
enzymes. Enzymes are
not micro-organisms but
are formed as a result of
the metabolism of micro-
organisms. The ability
of enzymes to trigger
chemical reactions can
be important when UHT
products are produced.
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Long Life Dairy, Food and Beverage Products
Some of the bacterial enzymes are able to cause sweet coagu-
lation of milk products, which destroys the product. The majority
of these enzymes are produced by Gram negative Pseudomonas
bacteria developing mainly in cold raw milk stored for exces-
sive time in milk cooling tanks, road tankers or milk silos. This
problem will be aggravated if the milk has been contaminated
because of unhygienic conditions or lack of cleaning-in-place
(CIP). The vast majority of enzymes will be destroyed by UHT
treatment, but a few may still be active in the final product.
MOU LD S
Moulds belong to the fungi group of micro-organisms, which
are very widely distributed in nature among plants, animals and
human beings. Moulds normally grow anaerobically, and their
optimum growth temperature is between 20 and 30°C. Moulds
can grow in substrates with pH 2 to 8.5, but many species prefer
an acid environment. The most common species in milk do not
survive pasteurisation conditions, and the presence of mould
in pasteurised products is therefore a sign of reinfection. The
penicillium family is one of the most common types of moulds.
Their powerful protein splitting properties make them the chief
agent in ripening of, for instance, Blue Cheese.
YEAST
Yeast also belong to the fungi group of micro-organisms. They
vary greatly in size. Saccharomyces cerevisiae, used for brewing
of beer, has a diameter of 2 to 8 micron, but other species may
be as large as 100 micron.
Yeast has the ability to grow both in the presence and absence
of oxygen. The optimum temperature is between 20 and 30°C.
Optimum pH values are 4.5 to 5.0, but yeast will grow in the pH
range of 3 to 7.5.
From a dairy point of view, yeast are generally undesirable
organisms. They ferment milk and cream and cause defects in
cheese and butter. In the brewing, baking and distillation indus-
tries, on the other hand, they are very valuable organisms.
BACTE R IOPHAG E S
Bacteriophages belong to the group of micro-organisms called
viruses. Viruses have no metabolism of their own and therefore
cannot grow on a nutrient substrate. Viruses infect living cells
in plants and animals. Bacteriophages (also known as phages)
infect bacteria and are consequently a problem in all dairy pro-
cesses where bacteria cultures are used. They are very small in
size – in the order of 0.02 to 0.06 micron and can only be seen
in an electron microscope.
Bacteriophages grow at temperatures between 10 and 45°C.
They are killed by exposure to 63 to 88°C for 30 minutes and
tolerate pH values in the range of 3 to 11.
TOXICITY
Micro-organisms, which are harmful to man or animals are
called pathogens. They can cause death or severe illness by the
secretion of toxins either directly into contaminated foodstuffs,
which are subsequently eaten, or by transfer to an animal host
offering ideal conditions for reproduction and further generation
of toxins. Some toxins are inactivated by heat treatment at 60°C
for one hour.
Process classificationA number of different expressions are commonly used in the
food industry in relation to food preservation. This section will
briefly describe the most common terms used.
PASTE U R I SATION
Most commercial liquid food products undergo some form of
heat treatment, and pasteurisation is the most common.
As it is usually bacterial growth that causes food to deteriorate,
pasteurisation preserves the freshness of the food product.
There are basically two ranges of pasteurisation:
• Low-temperature pasteurisation. For milk, this is based
on heating the product to 72 to 76°C and holding at that
temperature for at least 15 to 20 seconds (or equivalent) (Fig. 1).
The pasteurisation may vary from country to country
according to national legislation. A common requirement
in all countries, however, is that the heat treatment must
guarantee the destruction of unwanted micro-organisms and
all pathogenic bacteria.
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Temperature
Time
135ºCPure-LacTM
85ºCHigh pasteurisation
72ºCLow pasteurisation
Fig. 1: Low-temperature pasteurisation.
ºC150
100
50
0Time
High Heat Infusion
Direct Infusion
Indirect UHT
Fig. 2: Temperature profiles for direct infusion, high heat infusion and indirect UHT processes.
ºC150
100
50
010 20 30 40 50 60
MinutesFig. 3: Temperature profiles for conventional in-container sterilisation.
8
Long Life Dairy, Food and Beverage Products
The shelf life of pasteurised milk is limited (typically 5 to 7
days) and primarily depends on raw milk quality and storage
temperature.
During the low-temperature pasteurisation the phosphatase
enzyme is destroyed, while the peroxidase enzyme is
preserved. This serves as a measure to control the process
and distinguish it from high-temperature pasteurisation.
• High-temperature pasteurisation. This is based on heating the
product to 85°C or higher for a few seconds (or equivalent)
(Fig. 1 above). The aim is to kill the entire population of
bacteria, which are pathogenic for both man and animals
and almost all other bacteria as well. By careful monitoring
of the process parameters a product with excellent quality
can be obtained with minimum heat damage. The shelf life
can be extended to several weeks in the cooling chain. The
so-called Pure-LacTM process is based on high-temperature
pasteurisation.
During the high-temperature pasteurisation both the phos-
phatase and the peroxidase enzymes are destroyed, and this
serves as a measure to control that the process has actually
taken place as specified.
EXTE N D E D S H E LF LI FE
The term extended shelf life or ESL is being applied more and
more frequently.
There is no single general definition of ESL. Basically what
it means is the capability to extend the shelf life of a product
beyond its traditional well-known and generally accepted shelf
life without causing any significant degradation in product qual-
ity. A typical temperature/time combination for high-temperature
pasteurisation of ESL milk is 125 to 130°C for 2 to 4 seconds.
This is also known in the USA as ultra-pasteurisation.
SPX FLOW has in recent years developed a patented process
where the temperature may be raised to as high as 135°C but
only for fractions of a second. This is the basis for the Pure-
LacTM process described in a separate chapter, see table of
contents.
U HT TR EATM E NT
UHT – or Ultra High Temperature – treatment is based on the
fact that higher temperatures permit a much shorter processing
time. By proper time and temperature combination it is possible to
achieve commercial sterility with only limited undesirable chemi-
cal changes in the product. In terms of nutritive value, flavour and
appearance, the quality of the product is more vulnerable to the
duration of the treatment than to the temperature applied.
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Long Life Dairy, Food and Beverage Products
In the UHT process, the milk is typically heated to 137 to 150°C
and held at that temperature for just a few seconds before it
is cooled rapidly down to room temperature (Fig. 2 ). After the
product has been cooled it is led to an aseptic filling machine in
a closed piping system – either directly or by way of an aseptic
storage tank. The product obtained in this way has a shelf life at
room temperature of several months.
The quality of the final product depends on the raw material
quality but also to a large extent on the type of heat treatment
system applied. This is the case for UHT milk and for a wide
range of long life food products like sauces, salad dressings,
mayonnaise and soups, as well as for juices and soft drinks.
In order to combat the Heat Resistant Spores (HRS) SPX FLOW
developed the patented so-called High Heat Infusion system
enabling heat treatment temperatures as high as 150ºC without
adversely affecting the product quality and still maintaining ac-
ceptable running times in the order of 24 hours between cleaning.
Products with very high viscosity are more difficult to handle in
a UHT system, and SPX FLOW developed a special patented
version of the infusion system to handle high viscosity products.
This so-called Instant Infusion system is based on very short
but controllable and well defined retention time in the infusion
chamber.
STE R I LI SATION
Sterilisation is another type of heating process used for prod-
ucts to increase keeping quality without refrigeration. The heat
treatment takes place after the product is packed. The package
with its content is heated to approx. 120°C and held at that tem-
perature for 10 to 20 minutes after which it is cooled to room
temperature (Fig 3 on page 8). Because of the lengthy heat
treatment at a relatively high temperature this process reduces
the nutritive value of the product, and it is also liable to change
its colour and flavour considerably.
E U CLASS I FICATION
In the EU Milk Hygiene Directive (92/46) it is suggested that
“limits and methods to enable a distinction to be made between
different types of heat treated milk” may be established (Article
20).
The proposed parameters, limits and methods may be summa-
rised as shown in Table 2 .
By this method the hygienic requirements concerning food
safety can be satisfied taking into consideration the keeping
qualities over varying length of time. This method also makes it
possible to establish a new definition of different types of fluid
milk products in a way that is independent of the technology of
the heat treatment and the filling such as for instance, Pure-
LacTM.
It should be noted that the chemical criteria in Table 2 are the
recommendation given by IDF and EU to the legislators, but the
general perception is that this proposal will be followed.
M I LK HYG I E N E D I R ECTIVE 92/46/ E U
TH E R M I S E D PASTE U R I S E D H IG H TE M PE RATU R EPASTE U R I S E D HTP U HT STE R I LI S E D
63 - 65ºC/15 S E C . 71 .7ºC/15 S E C .O R E Q U IVALE NT >135ºC AN D >1 S E C . >135ºC AN D > 1 S E C .
P H O S P HATAS E+ P H O S P HATAS E-P E R OX I DAS E+
P H O S P HATAS E-P E R OX I DAS E-
15 DAYS AT 30ºC O R7 DAYS AT 55ºC 0 ⇒
<10 C F U /0 .1 M L
15 DAYS AT 30ºC O R7 DAYS AT 55ºC 0 ⇒
<10 C F U /0 .1 M L
** * * * * * *
B ETA-LACTO G LO B U LI N> 2600 M G / L
&
B ETA-LACTO G LO B U LI N> 2000 M G / L
&
> 50 M G / L&
B ETA-LACTO G LO B U LI N< 50 M G / L
O R
LACTU LO S EN OT D ETE CTAB LE
LACTU LO S E< 40 M G / KG
LACTU LO S E< 600 M G / KG
LACTU LO S E> 600 M G / KG
Table 2: Present legislation according to EU directive 92/46 ** IDF & EU suggestions for Dual Chemical Criteria
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 9 27/06/2018 07.38
10
Long Life Dairy, Food and Beverage Products
All UHT processes are designed to achieve commercial
sterility. This calls for application of heat to the product and a
chemical sterilant or other treatment that render the equipment,
final packaging containers and product free of viable micro-
organisms able to reproduce in food under normal conditions of
storage and distribution. In addition it is necessary to inactivate
toxins and enzymes present and to limit chemical and physical
changes in the product. In very general terms it is useful to have
in mind that an increase in temperature of 10°C increases the
sterilising effect 10-fold whereas the chemical effect only in-
creases approximately 3-fold. In this section we will define some
of the more commonly used terms and how they can be used for
process evaluation.
TH E LOGAR ITH M IC R E D UCTION OF S POR E S
AN D STE R I LI S I NG E FFICI E NCY
When micro-organisms and/or spores are exposed to heat treat-
ment not all of them are killed at once.
However, in a given period of time a certain number is killed
while the remainder survives. If the surviving micro-organisms
are once more exposed to the temperature treatment for the
same period of time an equal proportion of them will be killed.
On this basis the lethal effect of sterilisation can be expressed
mathematically as a logarithmic function:
A logarithmic function can never reach zero, which means that
sterility defined as the absence of living bacterial spores in an
unlimited volume of product is impossible to achieve. Therefore
the more workable concept of “sterilising effect” or “sterilising
efficiency” is commonly used.
The sterilising effect is expressed as the number of decimal
reductions achieved in a process. A sterilising effect of 9 indi-
cates that out of 109 bacterial spores fed into the process only
1 (100) will survive.
Spores of Bacillus subtilis or Bacillus stearothermophilus are
normally used as test organisms to determine the efficiency of
UHT systems because they form fairly heat resistant spores.
TE R M S AN D EXPR E SS ION S TO
CHARACTE R I S E H EAT TR EATM E NT
PROCE SS E S
Q10 value. The sterilising effect of heat sterilisation increases
rapidly with the increase in temperature as described above.
This also applies to chemical reactions, which take place as a
consequence of an increase in temperature. The Q10 value has
been introduced as an expression of this increase in speed of
reactions and specifies how many times the speed of a reac-
tion increases when the temperature is raised by 10°C. Q10 for
flavour changes is in the order of 2 to 3, which means that a
temperature increase of 10°C doubles or triples the speed of
the chemical reactions.
A Q10 value calculated for killing bacterial spores would range
from 8 to 30 depending on the sensitivity of a particular strain to
the heat treatment.
D-Value. This is also called the decimal reduction time and is
defined as the time required to reduce the number of micro-
organisms to one-tenth of the original value corresponding to a
reduction of 90%.
Z-Value. This is defined as the temperature change which gives
a 10-fold change in the D-value.
F0 value. This is defined as the total integrated lethal effect
and is expressed in terms of minutes at a selected reference
temperature of 121.1°C. F0 can be calculated as follows:
F0 = 10(T - 121.1) /z · t / 60 , where
T = processing temperature (°C)
z = Z-value (°C)
t = processing time (seconds)
Process evaluation
K · t = log N/Nt , where
N = number of micro-organisms/spores originally present
Nt = number of micro-organisms/spores present after a
given time of treatment (t)
K = constant
t = time of treatment
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 10 27/06/2018 07.38
2.7 2.6 2.5 2.4 2.3
1T
4000
2000
3000
1000
800
900
600
700
400
500
200
300
100
80
60
70
90
40
50
20
30
10
8
6
4
5
7
9
2
3
1110100 120 130 140 150 160ºC
loss of thiamine = 80%
threshold range of discolouration
loss of thiamine = 3% / C*=1
HM
F 1 µmol/l
HMF 100 µm
ol/l
HMF 10 µm
ol/l
60%
40%
10%
loss of lysine = 1%
lactulose 600 mg/l
lactulose 400 mg/l
20%
region ofsterilisation
thermal death value =
9
thermophilic spor
es / B*=
1
UHT-region
Hea
ting
time
or e
quiv
alen
t hea
ting
time
in s
econ
ds
·10 in K3 -1
Fig. 4: Bacteriological and chemical changes of heated milk (H.G. Kessler).
11
Long Life Dairy, Food and Beverage Products
F0 = 1 after the product has been heated to 121.1°C for one
minute. To obtain commercially sterile milk from good quality raw
milk, for example, an F0 value of minimum 5 to 6 is required.
B* and C* Values. In the case of milk treatment some countries
are using the following terms:
• Bacteriological effect:
B* (known as B star)
• Chemical effect
C* (known as C star)
B* is based on the assumption that commercial sterility is
achieved at 135°C for 10.1 seconds with a corresponding Z-
value of 10.5°C; this reference process is giving a B* value of
1.0, representing a reduction of thermophilic spore count of 109
per unit (log 9 reduction).
The B* value for a process is calculated similarly to the F0 value:
B* = 10 ( T - 135 ) / 10.5 · t / 10.1, where
T = processing temperature (°C)
t = processing time (seconds)
The C* value is based on the conditions for a 3 percent destruc-
tion of thiamine (vitamin B1); this is equivalent to 135°C for 30.5
seconds with a Z-value of 31.4°C. Consequently the C* value
can be calculated as follows:
C* = 10 ( T - 135 ) /31.4 · t / 30.5
Fig. 4 on the right shows that a UHT process is deemed to be
satisfactory with regard to keeping quality and organoleptic
quality of the product when B* is > 1 and C* is < 1.
The B* and C* calculations may be used for designing UHT
plants for milk and other heat sensitive products. The B* and
C* values also include the bacteriological and chemical effects
of the heating up and cooling down times and are therefore
important in designing a plant with minimum chemical change
and maximum sterilising effect.
The more severe the heat treatment is, the higher the C* value
will be. For different UHT plants the C* value corresponding
to a sterilising effect of B* = 1 will vary greatly. A C* value of
below 1 is generally accepted for an average design UHT plant.
Improved designs will have C* values significantly lower than 1.
The APV Steam Infusion Steriliser has a C* value of 0.15.
R E S I D E NCE TI M E
Particular attention must be paid to the residence time in a hold-
ing cell or tube and the actual dimensioning will depend on sev-
eral factors such as turbulent versus laminar flow, foaming, air
content and steam bubbles. Since there is a tendency to operate
at reduced residence time in order to minimise the chemical
degradation (C* value < 1) it becomes increasingly important to
know the exact residence time.
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ToVacuumChamber
TURBULENT FLOW OF IS WELL DEFINEDLIQUID
V
ToVacuumChamber
SIGHT GLASS
SIGHT GLASS
V1V2
3V
HOLDING TIME NOT DEFINED
V > V > V3 2 1
Holding Tube without Centrifugal Pump
Holding Tube with Centrifugal Pump
From otherDirect UHT Systems
Multi-phase system:
Single-phase system:
From APV InfusionChamber
Fig. 5: Holding Tube.
80 90 100 110 120 130 140
Type A deposit
Deposit build-up
Type B deposit
Temperature, ºC
Inlet to Heater Milk Flow Outlet to Holding Tube
Fig. 6: Deposits in UHT plants.
12
Long Life Dairy, Food and Beverage Products
In SPX FLOW the infusion system has been designed with a
special pump mounted directly below the infusion chamber, which
ensures a sufficient over-pressure in the holding tube in order to
have a single phase flow free from air and steam bubbles.
This principle enables SPX FLOW to define and monitor the
holding time and temperature precisely and makes it the only
direct steam heating system, which allows true validation of flow
and temperature at the point of heat transfer.
The concept is illustrated in Fig. 5.
COM M E RCIAL STE R I LITY
The expression of commercial sterility has been mentioned
previously and it has been pointed out that complete sterility in
its strictest sense is not possible. In working with UHT products
commercial sterility is used as a more practical term, and a
commercially sterile product is defined as one which is free from
micro-organisms which grow under the prevailing conditions.
CH E M ICAL AN D BACTE R IOLOG ICAL
CHANG E S AT H IG H TE M PE RATU R E S
Heating milk and other food products to high temperatures re-
sults in a range of complex chemical reactions causing changes
in colour (browning), development of off-flavours and formation
of sediments. These unwanted reactions are largely avoided
through heat treatment at a higher temperature for a very short
time, and it is important to seek the optimum time/temperature
combination, which provides sufficient kill effect on spores but,
at the same time, limits the heat damage, in order to comply with
market requirements for the final product.
Even though the time/temperature combination is decisive for
the final quality of the product attention also has to be paid to
the actual heating profile since various reactions take place at
different temperatures. This is illustrated in Fig. 6 in which type
A deposit is a voluminous protein-rich deposit, whereas type
B deposit is a mineral rich deposit developing primarily at high
temperatures. In particular type A deposit, which originates from
protein denaturation, must be minimised since it is harmful to
the product quality.
RAW MATE R IAL QUALITY
It is important that all raw materials are of very high quality as
the quality of the final product will be directly affected. Raw ma-
terials must be free from dirt and have a very low bacteria spore
count, and any powders must be easy to dissolve.
All powder products must be dissolved prior to UHT treatment
because bacteria spores can survive in dry powder particles
even at UHT temperatures. Undissolved powder particles will
also damage homogenising valves causing sterility problems.
Heat stability. The question of heat stability is an important
parameter in UHT processing.
Different products have different heat stabilities and although
the UHT plant will be chosen on this basis it is desirable to be
able to measure the heat stability of the products to be UHT
treated.
For most products this is possible by applying the alcohol test.
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13
Long Life Dairy, Food and Beverage Products
When samples of milk are mixed with equal volumes of an ethyl
alcohol solution the proteins become unstable and the milk floc-
culates.
The higher the concentration of ethyl alcohol is without floccula-
tion the better the heat stability of the milk.
Production and shelf life problems are usually avoided provided
the milk remains stable at an alcohol concentration of 75%.
High heat stability is important because of the need to produce
stable homogeneous products, but also to prevent operational
problems like fouling in the UHT plant. This will decrease run-
ning hours between CIP cleanings and thereby increase product
waste, water, chemical and energy consumption.
Generally it will also disrupt smooth operation and increase the
risk of insterility.
S H E LF LI FE
The shelf life of a product is generally defined as the time for
which the product can be stored without the quality falling below
a certain minimum acceptable level. This is not a very sharp and
exact definition and it depends to a large extent on the percep-
tion of “minimum acceptable quality”. Having defined this it will
be raw material quality, processing and packaging conditions
and conditions during distribution and storage, which will deter-
mine the shelf life of the product.
Milk is a good example of how wide a span the concept of shelf
life covers:
The usual organoleptic factors limiting shelf life are deteriorated
taste, smell and colour, while the physical and chemical limiting
factors are incipient gelling, increase in viscosity, sedimentation
and cream lining.
In order to be able to produce a product with specific product
qualities in the most cost-effective way it is essential to make the
correct choice with respect to processing system and technology.
In many cases the choice is straightforward, but in other cases
there may be more options to choose between. Some of the
more important questions to ask when choosing a system are:
• What is the specification of the product to be processed?
• Which are the quality requirements to the final product?
• Viscosity specifications of products and raw materials?
• Specification of particulate and fibre content/size and shape
and variation in content?
• Acidity of product/high or low acid?
• Sensitivity to high temperatures/heat stability?
• Requirement for flexibility/multi-purpose systems?
• Requirement for variable capacity?
• Requirement for direct or indirect systems?
• Skills of technical personnel/operators?
Fig. 7 on page 14 illustrates three of the selection criteria –
viscosity, capacity and content of particulates – for the most
common processing systems.
The systems are often flexibly designed to allow for processing
a range of products in the same plant.
It is quite common to process both low-acid (pH>4.5) and high-
acid (pH<4.5) products in the same UHT plant.
However, only low-acid products require UHT treatment to make
them commercially sterile.
Spores cannot develop in high-acid products such as juice, and the
heat treatment is therefore only intended to kill yeast and moulds.
Consequently high temperature pasteurisation at 90 - 95°C for
15 to 30 seconds is sufficient to make most high-acid products
commercially sterile.
In some cases where new products have to be processed it may
be necessary to carry out trials in small scale to observe the
performance of specific products in different types of systems.
SPX FLOW has designed a pilot unit for this purpose.
PROD UCT SHELF LIFE STORAGE
PASTE U R ISE D M I LK 5 TO 10 DAYS R E FR IG E RATE D
ESL/ PU R E-LAC TM 20 TO 45 DAYS R E FR IG E RATE D
U HT M I LK 3 TO 6 MONTH S AM B I E NT TE M P.
Choosing the right process
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 13 27/06/2018 07.38
Fig. 7: Aseptic processing systems.
Capacity l/h35.000 l/h
50 cP
200 cP100 cP
50,000 cP
500 cP
Plate Steriliser
Steam Injectio
n Steriliser
Steam Infusio
n Steriliser
Tubular Sterili
ser
SSHE Steriliser
Increasingparticle size
Viscosity cP
14
Long Life Dairy, Food and Beverage Products
The trend for processors to focus increasingly on flexibility to
process a range of products and the importance of being able to
produce high quality products has driven the choice of systems
towards indirect tubular systems and direct steam infusion
systems.
The following sections will deal with the various heating princi-
ples and UHT systems followed by a more detailed comparison
of the individual systems.
TH E H EAT TR EATM E NT PROCE SS E S
SPX FLOW invented the plate heat exchanger in 1923 and has
ever since pioneered new heat treatment principles. Scraped
surface heat exchangers were developed in the USA while the
direct steam infusion system was developed in Denmark. The
tubular systems were developed partly in Denmark and partly
in Germany and later supplemented by the corrugated tubular
heat exchangers in Spain. In addition SPX FLOW is known for
electroheat thermal processing equipment, which is dealt with in
a separate publication.
PLATE H EAT EXCHANG E R S
The plate heat exchanger is the most cost-effective and versatile
method for indirect heating or cooling of liquid food pro ducts.
Today SPX FLOW’s comprehensive Paraflow range of plates
is the basis for a wide range of plate heat exchanger applica-
tions in many industries, and in the food and dairy industry the
plate heat exchanger is one of the most indispensable pieces of
equipment.
As illustrated in Fig. 8.1 on page 15 the plate heat exchanger
incorporates a number of parallel, closely spaced stainless
steel, gasketed and corrugated plates, which are compressed
and locked together in a rugged frame. As product is pumped
through the plate heat exchanger, the flow is distributed through
narrow, corrugated flow passages, which produce a high level of
turbulence resulting in high rates of heating or cooling with low
hold-up volume. Product contact time is thereby reduced to a
matter of seconds minimising thermal damage.
A very important advantage of the plate heat exchanger is its
extremely high regenerative capability, reducing energy require-
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 14 27/06/2018 07.38
Fig. 8.3.1: APV Double Tube.
Fig. 8.3.2: APV Triple Tube.
Fig. 8.3.4: APV Multi-Tube-in-Tube.
Fig. 8.3.3: APV Quadruple Tube.
Fig. 8.1: APV Plate Heat Exchanger.
Product in Product out
Media inMedia out
Fig. 8.2: APV Tubular Heat Exchanger.
Media out
Media in
Productout
Productin
15
Long Life Dairy, Food and Beverage Products
ments for heating or cooling by more than 90%. Plate heat ex-
changers provide a maximum amount of heat exchange surface
in a minimum amount of floor space.
TU B U LAR H EAT EXCHANG E R S
SPX FLOW has developed a range of sanitary tubular heat
exchangers for the food industry, and an increasing number
of customers choose this system. Various tubular systems are
available, but the most commonly used system is the multi-tube-
in-tube (MTNT) system as illustrated in Fig. 8.2. The heat trans-
fer modules are multiple small diameter sanitary tubes aligned
within a large diameter shell.
The diameter of the inner tubes may vary, but is usually in the
range of 10 to 12 mm for low viscous products like milk and
juice.
The SPX FLOW tubular system is designed with a “loose” jacket
around the tube bundles giving a floating head design.
This allows thermal expansion without any risk of tube cracking,
prevents stress corrosion and allows easy inspection of all heat
exchange surfaces.
In some countries, e.g. Germany, the tubular system has become
very popular because of its rugged construction and easy opera-
tion and maintenance.
COR R UGATE D TU B U LAR H EAT EXCHANG E R S
SPX FLOW has extended its range of heat exchangers with cor-
rugated tubular heat exchangers. By corrugating the tube wall it
is possible to improve the heat transfer coefficient and conse-
quently reduce the requirement for heating surface area. The
corrugation causes increased turbulence and breaks the laminar
flow in high viscosity products.
Double-tube, triple-tube, quadruple-tube and multi-tube are the
basis for the range as illustrated in Fig. 8.3.1, 8.3.2, 8.3.3 and
8.3.4. The design of the double-, triple- and quadruple-tube
makes it possible to arrange direct regeneration because both
sides of the tube wall are a sanitary design.
Through a variety in corrugation depth, pitch and angle it is pos-
sible to optimise heat transfer and pressure drop depending on
shear characteristics of the product. Furthermore, the possibility
of adjusting the annular space adds one further parameter for
optimising the design.
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 15 27/06/2018 07.38
Steam
Product
Fig. 8.4: APV Steam Injection Nozzle.
Air out
CIP in
Holding tube
Steam in Product in
Cooling waterin/out
Fig. 8.5: APV Steam Infusion Chamber.
16
Long Life Dairy, Food and Beverage Products
STEAM I NJ ECTION NOZ Z LE S
SPX FLOW was one of the pioneers in applying steam in direct
contact with a product to heat it to aseptic temperatures. The
first generation systems were based on the steam injection prin-
ciple and were launched under the Uperiser brand name.
The system operates by direct injection of steam through a
specially designed nozzle as illustrated in Fig. 8.4. The injection
of steam raises the product temperature instantly. In order to
prevent the product from boiling it is necessary to pressurise the
product during the steam injection to a pressure of 3 to 4 bar
depending on the sterilisation temperature.
Flash cooling takes place in a vacuum expansion vessel where
the vacuum is maintained by means of a vacuum pump. The
vacuum is controlled in order to ensure that the same amount
of water is flashed off as was injected into the product as steam
thereby preventing dilution/concentration of the product.
STEAM I N FUS ION
In the 1960s APV, An SPXFLOW Brand, launched the first steam
infusion system under the Palarisator brand name. Since then sig-
nificant developments and progress have taken place, which have
led to one of the most sophisticated systems in the world.
After pre-heating the product is pumped into the infuser, which
is a pressure vessel fitted with cones at both top and bottom as
illustrated in Fig 8.5.
At the top cone the product is distributed through a number of
nozzles (patented) and passes down through a steam atmos-
phere in a number of jets without hitting the walls of the vessel
until it reaches the bottom cone.
This is equipped with a cooling jacket keeping the temperature
of the inner cone wall below the product temperature inside the
vessel. This creates a condensate film on the inner cone wall,
which effectively prevents any burn-on of product. During the
heating air, unwanted gases and odours are stripped off through
the CIP inlet at the top of the cone.
The product leaves the infusion chamber through the bottom
of the cone through a pump and an expansion valve before
it passes through the holding tube into the expansion vessel
where the product is cooled down in a similar way as described
for the injection heating system.
As previously mentioned (Fig. 5 on page 12) this system ensures
a single phase flow and a very accurate flow profile.
The pump and the valve in the holding tube also serve as level
control, which means that there is no product level prior to the
pump and consequently no influence on the holding time due to
varying liquid level at the bottom of the cone, since it will always
be empty.
The heating in the infuser is extremely rapid, and the final steri-
lisation temperature is reached in less than 0.2 seconds, which
corresponds to a heating rate of 500 to 600ºC/second.
The system is very flexible and can be used for a wide range
of products covering a broad viscosity range. It provides an
excellent product quality due to the gentle and rapid heating and
subsequent cooling.
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 16 27/06/2018 07.38
Product out Product in
Media in Media out
Fig. 8.6: APV Scraped Surface Heat Exchanger.
Fig. 9: APV VT+660 Scraped Surface Heat Exchanger.
PRODUCT FILLING
STEAM
1. Product to productregenerative
2. Homogeniser4. Holding tubes5. Indirect cooling
6. Sterile tank7. Cip unit8. Sterilising loop
COOLINGWATER
31
2
6
7
8
5ºC 75ºC
3 5
CHILLEDWATER
4 490ºC 138ºC
5
<25ºC25ºC
3. Indirect heating
Fig. 11.1: Flowdiagram for Plate Steriliser.Fig.10: APV HD Scraped Surface Heat Exchanger.
17
Long Life Dairy, Food and Beverage Products
SCRAPE D SU R FACE H EAT EXCHANG E R S
SPX FLOW’s product range includes a number of scraped sur-
face heat exchangers specially designed to heat or cool viscous
or sticky products or products containing particulates.
The scraped surface heat exchanger consists of a smooth cylin-
der through which the product is pumped, counter current to the
service medium in the surrounding jacket.
Rotating scraper blades keep the heating surface free from
deposits. The scraper blades are fixed to a rotating shaft called
a dasher (Fig. 8.6).
Selection of different blades and dasher types depends on the
product being processed. The cylinders are usually character-
ised by their diameter and SPX FLOW supplies units of 4, 6 and
8 inches.
Furthermore, both vertical (Fig. 9) and horizontal models
(Fig. 10) are available.
The most recent addition to the range is a VT+660 model with
0,65 m2 surface area, which is 41 percent higher than for the 4”
range.
The maximum operating pressure for the VT range is 6 bar while
the HD range is able to operate at 12 bar maximum pressure.
In terms of viscosity the VT model is able to process products
with viscosity up to 100,000 cP.
The HD range is a Heavy Duty model able to handle viscosity as
high as 500,000 cP.
Various aseptic UHT systemsThe best way to characterise UHT systems is to rank them ac-
cording to the primary type of heating principle used for bringing
the product into the aseptic area.
The type of system preferred has developed differently in differ-
ent countries at different times. In the following section we will
give a brief description of each type of system available on the
market today. For each system the advantages and limitations
will be emphasised and finally the products most commonly
processed in the system will be listed.
All SPX FLOW UHT systems are pre-assembled and tested in
the factory with steam. This minimises installation and start-up
costs and ensures a safe and trouble-free plant commissioning.
I N D I R ECT PLATE STE R I LI S E R
UHT systems based on plate heat exchangers are used where
the manufacturer’s primary requirement is a dependable system
for heating liquid products at minimum operating costs.
In Fig. 11.1 a flow diagram illustrates the principle design includ-
ing some of the processing parameters.
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 17 27/06/2018 07.38
Fig. 11.3: APV Plate Steriliser.
LOW MEDIUM HIGH
Energy recovery
PLATE
TUBULAR
LOW MEDIUM HIGH
Plant volume at 90% regenerative
PLATE
TUBULAR
Fig. 11.2: Comparison of data for Plate and Tubular Steriliser.
LOW MEDIUM HIGH
Product shear at equivalent heat transfer
PLATE
TUBULAR
LOW MEDIUM HIGH
Heat transfer at equivalent surface
PLATE
TUBULAR
18
Long Life Dairy, Food and Beverage Products
Careful design of the heating and regenerative systems opti-
mises the performance of the system and minimises product
damage. Fig. 11.2 above compares some key data for plate and
tubular systems.
The SPX FLOW system has a high degree of flexibility and can
be supplied with variable capacity and with two-speed or vari-
able speed homogenisers.
The system can be built up to a maximum capacity of 25 to
30,000 l/h.
Fig. 11.3 shows a typical design for an APV Plate Steriliser.
Advantages
• Excellent for low viscosity products
• High regenerative effect and low energy consumption
• High heat transfer area in minimal space
• Easy inspection
• Low hold-up volume
• High degree of flexibility
• Variable capacity
• Large capacity plants
• Relatively low investment
• Low CIP costs
Limitations
• Limited capability for particulates or fibres
• Exchange of gaskets required periodically
• Unsuitable for high pressure drops
• Some product degradation may occur
Products
• Milk, flavoured milk
• Fermented milk products, drinking yogurt
• Cream, coffee whiteners
• Soy milk
• Baby food
• Juice
• Coffee, tea
• Combination plants for milk, juice, coffee, tea, etc.
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 18 27/06/2018 07.38
Fig. 12.3: APV Tubular Steriliser.
PRODUCT FILLING
4
8
5
10
6
79
5ºC
75ºC
21 1
95ºC 140ºC
25ºC
STEAM
COOLINGWATER
1. Tubular regenerativepreheaters
2. Homogeniser3. Holding tubes
4. Tubular final heater5. Tubular regenerative
cooler6. Final cooler
7. Sterile tank8. CIP unit9. Sterilising loop10. Water Heater
3 3
Fig. 12.1: Flow diagram for Tubular Steriliser.
Fig. 12.2: Comparison of data for Tubular and Plate Steriliser.
Running time (hours)0 84 12 16 20 24
Tubular UHTPlate UHT
Tolerated pressure drop (bar)0 50 80 90706010 20 30 40 100
Tubular UHTPlate UHT
10 305 252015
Particle sizes/Fibre lengths (mm)
Tubular UHTPlate UHT
19
Long Life Dairy, Food and Beverage Products
I N D I R ECT TU B U LAR STE R I LI S E R
UHT systems based on tubular heat exchangers have become
popular in many countries and are typically chosen where large
volumes of commodity products has to be processed at the low-
est possible costs.
In Fig. 12.1 a flow diagram illustrates the principle design includ-
ing some of the processing parameters.
In Fig. 12.2 it is shown how the pressure drop affects the maxi-
mum running hours. In a plate based steriliser the increase in
pressure drop is limited to 30 to 40 percent.
This is not a limiting factor in tubular systems and 16 to 20
hours operating time between CIP is possible. It is also possible
to operate with an intermediate cleaning each 20 hours and
reduce the full CIP cycles to once a week, which may increase
the capacity with as much as 7 to 9 percent.
Exact times will depend on particular products and microbiologi-
cal considerations.
Advantages
• Less vulnerable to fouling giving long production runs
• High operating pressures are acceptable
• Processes products with fibres and particulates
• Processes high viscosity products
• Low shear characteristics for cream
• Low requirement for gasket material and easy gasket exchange
• Very robust design
• Low maintenance costs
• Can be designed as a multi-purpose plant
• Easy to operate
Limitations
• Lower regenerative effect than for plate sterilisers
• Slightly higher investment costs compared with plate sterilisers
• Higher degree of product degradation
Products
• Milk, flavoured milk
• Fermented milk products, drinking yogurt
• Cream, coffee whiteners
• Whipping cream, ice cream mix
• Evaporated milk, desserts, puddings
• Soy milk
• Coffee, tea
• Juices, juices with pulp
• Salad dressings
• Gravy, sauces, soups
• Combination plants for milk, juice, coffee, tea, etc.
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 19 27/06/2018 07.38
Fig. 13.3: APV Steam Infusion Steriliser.
5
25
50
75
100
125
ºC150
Time
Hot FillIing /Spray Drying
Filling
Cold Filling
Insta
nt
ESL UHT
Various Temperature Profiles for Direct Infusion
Fig. 13.2: Time/temperature profiles for various infusion based processes.
6 6
143ºC 75ºC 25ºC <25ºC
FILLING
5
7
VACUUM
STEAM
1. Plate preheaters2. Steam infusion chamber3. Holding tube
4. Flash vessel5. Aseptic homogeniser6. Plate coolers
7. Aseptic tank8. Non aseptic cooler9. Condenser
COOLINGWATER
2
STEAM
75ºC
COOLING
COOLING
WATER
WATER
4
9
3
1
PRODUCT
5ºC
8 COOLINGWATER
Fig. 13.1: Flow diagram for Steam Infusion Steriliser.
20
Long Life Dairy, Food and Beverage Products
STEAM I N FUS ION STE R I LI S E R
UHT systems based on the infusion heating are used where the
manufacturer wants to produce a high quality product with as
little heat degradation as possible. Also flexibility in throughput
and variety in product range speak for an infusion based system.
In Fig. 13.1 a flow diagram illustrates the principle design includ-
ing some of the processing parameters.
The system can basically be supplied from 150 l/h (pilot plant) to
44,000 l/hour with a temperature profile as shown in Fig. 13.2.
The plate heat exchangers for pre-heating and cooling can be
replaced with tubular heat exchangers as an option.
The SPX FLOW infusion UHT concept can also be supplied
as an add-on solution to all common UHT plants from other
manufacturers.
Fig. 13.2 shows a comparison of various temperature profiles for
infusion based processes, which are all characterised by a very
rapid and controlled heating and cooling profile and a short and
carefully monitored holding time.
Fig 13.3 shows an APV Steam Infusion Steriliser.
Advantages
• Gentle and accurate heating in the infusion chamber
• Accurate holding time
• Superior product quality
• Closed loop during pre-sterilising
• High product flexibility
• Low fouling rate
• Long operating time
• Operator friendly
Limitations
• Relatively higher capital costs compared to indirect systems
• Relatively higher operating costs due to lower heat regeneration
• Requirement for culinary steam
Products
• Milk, flavoured milk, creams
• Soy milk products
• Vla, custard, pudding
• Soft ice mix, ice cream mix
• Baby food, condensed milk
• Processed cheese
• Sauces
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 20 27/06/2018 07.39
PRODUCT
FILLING
64
9
VACUUM
COOLINGWATER
5
STEAM
711 7
5ºC 60ºC
2
90ºC 125ºC
2
810 8
150ºC 75ºC 25ºC
STEAMSTEAM
1. Tubular preheaters2. Holding tube3. Flash vessel (non aseptic)
4.5. Steam infusion chamber6.
Non aseptic flavour dosing (option)
Homogeniser (aseptic)
7.8.9.10.
Tubular coolersTubular HeatersAseptic tankNon aseptic cooler
COOLINGWATER
3
Fig. 14.1: Flow diagram for High Heat Infusion Steriliser.
UHT of products with HRS (comparative temperature profiles with Fo= 40)
0
50
100
150
Time
ºC
Direct UHT 150ºCHigh Heat Infusion 150ºCIndirect UHT 147ºCReference Indirect UHT 140ºC
Fig. 14.2: Time/temperature profiles illustrating High Heat Infusion processing parameters.
Fig.14.3: APV High Heat Infusion Steriliser.
21
Long Life Dairy, Food and Beverage Products
H IG H H EAT I N FUS ION STE R I LI S E R
The growing incidents of heat resistant spores (HRS) are chal-
lenging traditional UHT technologies and setting new targets.
The HRS are extremely heat resistant and require a minimum of
145 to 150°C for 3 to 10 seconds to achieve commercial steril-
ity. If the temperature is increased to this level in a traditional in-
direct UHT plant it would have an adverse effect on the product
quality and the overall running time of the plant. Furthermore it
would result in higher product losses during start and stop and
more frequent CIP cycles would have to be applied. Using the
traditional direct steam infusion system would result in higher
energy consumption and increased capital cost. On this basis
SPX FLOW developed the new High Heat Infusion system.
In Fig. 14.1 a flow diagram illustrates the principle design includ-
ing the most important processing parameters while
Fig. 14.2 shows the temperature/time profile in comparison to
conventional infusion and indirect systems.
Note that the vacuum chamber has been installed prior to
the infusion chamber. This design facilitates improvement in
energy recovery and it is possible to achieve 75% regeneration
compared to 40% with conventional infusion systems and 80 to
85% with indirect tubular systems.
Fig. 14.3 shows a design of a High Heat Infusion system deliv-
ered as a combi-plant consisting of an APV Tubular Steriliser
with the infuser module added on.
Advantages
• Micro-biological product safety by elimination of HRS spores
• Very long operating time between CIP
• Reduced contamination risk having vacuum chamber
• on non-aseptic side
• No flavour losses
• Add-on solutions and combi-systems
Limitations
• Capital investment costs
• Requirement for culinary steam
Products
• Milk and milk products
• Desserts
• Other products with conventional infusion systems
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 21 27/06/2018 07.39
Air out
Steam in
CIP in
Product in
Cooling water in/out
Fig. 15.1: Instant Infusion Chamber.
Fig. 15.2: APV Instant Infusion Pasteuriser.
22
Long Life Dairy, Food and Beverage Products
I N STANT I N FUS ION PASTE U R I S E R
The infusion heating principle has increasingly been used for
high viscous and sticky products. However, some products have
been found to be very difficult or nearly impossible to handle
unless very short run-times were accepted.
This challenge led SPX FLOW to develop the patented Instant
Infusion system. The objective was to design a system where a
high kill rate can be achieved using high pasteurisation tempera-
tures and very low holding time (<0.5 second) for products like
egg white and whey protein concentrate.
The patented design principle for the Instant Infusion Pasteur-
iser is based on the conventional infusion system.
In order to have an efficient removal of the viscous and sticky
product from the infusion chamber, a positive displacement
pump has been placed in the outlet tube from the bottom cone
very close to the actual cone.
This effectively prevents any type of build-up of product at the
bottom of the infusion chamber and it has been possible to
increase the number of operating hours between CIP cleanings
from a few to more than 20 hours for some products.
In Fig 15.1 is shown the design of the infusion chamber with the
pump arrangement.
Fig. 15.2 shows an industrial installation of an Instant Infusion
plant.
Advantages
• Can handle high fouling products with long running time (>20 hrs.)
• High degree of flexibility
• Reduced chemical changes in comparison to conventional infusion
• Very high product quality
Products
• Whey protein concentrate
• Egg-based products
• Baby food
• Processed cheese
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 22 27/06/2018 07.39
PRODUCT
6 6
143ºC 75ºC 25ºC <25ºC
FILLING
5
7
VACUUM5ºC
STEAM
1. Plate preheaters2. Steam injection nozzle3. Holding tube
4. Flash vessel5. Aseptic homogeniser6. Plate coolers
7. Aseptic tank8. Non aseptic cooler9. Condenser
2
STEAM
75ºC
COOLING
COOLING
WATER
WATER
4
9
3
1
8 COOLINGWATER
Steam
Product
Fig. 16.2: APV Steam Injection Steriliser.
Fig. 16.1: Flow diagram for Steam Injection Steriliser.
23
Long Life Dairy, Food and Beverage Products
STEAM I NJ ECTION STE R I LI S E R
This system operates by direct injection of steam into the prod-
uct through a specially designed nozzle as previously described
(Fig. 8.4 on page 16).
The heating is followed by flash cooling and final cooling, which
take place in either plate heat exchangers or tubular heat
exchangers.
The system is in its basic design quite similar to an infusion
system where the infuser has been replaced with an injection
nozzle. (Fig. 16.1)
Long operating times are possible because only a very small
area in the nozzle is subject to fouling.
The operating economy has been optimised through optimisa-
tion of plant design, processing parameters and careful process
control.
The injection system handles low to medium viscosity products,
in the capacity range from 2,000 to 25,000 l/hour.
Fig. 16.2 shows an APV Steam Injection Steriliser.
Advantages
• Good product quality
• Long production runs
• Handles heat-sensitive products
Limitations
• Higher capital costs than for indirect systems
• Higher operating costs due to lower heat regeneration
• Mostly used for low viscosity products
• Requirement for culinary steam
Products
• Milk, flavoured milk, cream
• Soy milk
• Ice cream mix
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Fig. 18: APV UHT Pilot Plant.
Fig. 17: APV SSHE Steriliser.
24
Long Life Dairy, Food and Beverage Products
SCRAPE D SU R FACE H EAT EXCHANG E R
STE R I LI S E R
Scraped surface heat exchangers (SSHE) are the most suitable
equipment for treatment of high viscosity food products and
food products containing larger particles.
In a typical aseptic plant the product is pumped by a rotary lobe
pump or similar to feed one or more heating cylinders followed
by a holding tube and one or more cooling cylinders. Capaci-
ties up to approximately 10,000 l/hour are available but this
depends to a large extent on the physical characteristics of
individual products.
Since the nature of the products can vary considerably in terms
of viscosity, stickiness or size and fragility of the particles, each
system is individually engineered to suit a particular product.
Even though systems based on SSHE are relatively expensive,
both in terms of investment and energy consumption, they are
still very competitive compared with batch sterilising systems.
Fig. 17 shows an SSHE based steriliser equipped with VT 4“
cylinders.
Advantages
• Handles high-viscosity products
• Handles sticky products
• Handles particulates up to approximately 13 mm
• Handles heavy-fouling products
Limitations
• Relatively high capital cost
• Relatively high energy requirements
• Higher maintenance costs owing to scraper blades,
bearings and seals
• High spare parts requirement
• Limitation in respect of size of particulates
Products
• Milk concentrate
• Yogurt
• Processed cheese
• Whey protein concentrate
• Quark products
• Baby food
• Compotes
• Puddings, dips
• Sauces, soups
PI LOT U HT PLANT
The constant pressure on manufacturers to produce quality
products at the lowest possible cost creates a need for evaluat-
ing the most suitable process system and optimising processing
parameters. Using production plants for tests on new products
and processes is both uneconomical and difficult.
Therefore SPX FLOW developed a new generation of pilot
plants, which gives manufacturers the possibility of performing
tests on a small scale with easy operation, flexibility and scaling
up accuracy.
The continuous UHT pilot plant Fig. 18 has a capacity of 60 to
200 l/h and is designed for indirect tubular and direct steam
infusion heating.
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 24 27/06/2018 07.39
Fig. 19: APV Sterile Tank.
25
Long Life Dairy, Food and Beverage Products
However, the following options can be included in the standard
system:
• High Heat Infusion
• Indirect Plate
• Direct Steam Injection
• Pasteurisation
• Deaeration/Deodorisation
• Scraped Surface Heat Exchanger
• and/or any combinations.
It is also possible to provide variable temperature and holding
time profiles. This makes the pilot plant extremely versatile. The
plant can be supplied with a 500 litre sterile tank, which will form
a link between the pilot plant and a filling machine.
Many manufacturers choose to invest in their own pilot plant for
in-house testing and product evaluation, but in other cases they
may choose to use one of SPX FLOW’s test and development
centres.
STE R I LE TAN K
It is not always practically possible to feed a sterile product
directly from the processing plant to the filling machine.
This is where the aseptic tank comes in as a buffer between
processing and filling units.
Besides serving as a buffer and storage tank for the sterilised
product the aseptic tank also adds an important degree of flex-
ibility to the production process as it provides for:
• Continuation of production regardless of interruption in filling
rate. Usually one UHT line is connected to several filling
machines with variable capacity. If the filling rate is not at a
maximum, the UHT plants need to have a variable capacity or
the product must be recirculated if allowed by local regulations.
• Continuation of filling during intermediate CIP or interruption
in UHT operations. Many UHT plants need intermediate
CIP after 8 to12 hours of operation, depending on the UHT
system, product quality and type of product to be processed.
The aseptic tank ensures that this process can be performed
without interrupting the operation of the filling lines.
• Reduced investment. As the filling machines are the most
expensive part of an aseptic processing line, it is important
that they are utilised to their full capacity. To this end the
aseptic tank is installed. By increasing the operating time of
the fillers, a small increase in the capacity of the UHT plant
creates the possibility of lengthening the production run
significantly.
The aseptic tank is equipped with steam-shielded aseptic valve
clusters and supplied with sterile air at constant pressure. This
provides for a perfect balance between supply and demand from
the aseptic tank.
The aseptic tank is also fully automated, using programmable
logic controllers (PLC), and the control system can be con-
nected either to the UHT control system or to one of the filling
machines.
Fig. 19 shows the APV Sterile Tank.
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 25 27/06/2018 07.39
Table 3: Comparison of various methods for reducing the number of bacteria and spores in liquid milk.
Fig. 20: APV Parasol Deaerator.
D ECI MAL R E D UCTION OF VAR IOUS BACTE R IA AN D S POR E S
TYPE CE NTR IFUGATION
M ICRO FI LTRATION PU R ELAC TM
TOTAL BACTE R IA 1 2.5 10
AE R O B I C S P O R E S 1.3 2.4 6
AE R O B I C P SYC H R O-TR O P H I C S P O R E S <1 2.4 8
AE R O B I C S P O R E S 1.7 4
26
Long Life Dairy, Food and Beverage Products
D EAE RATOR
Deaeration is essential for production of high quality products. While
the products in the infusion systems are deaerated in the infusion
chamber this is not the case when indirect heating systems are used.
In these cases the dearation can be solved through the installa-
tion of the APV Parasol Deaerator, designed to remove dis-
solved or entrained air under vacuum. The product is sprayed
into a vessel as a thin film in a parasol form, maximising product
surface area and deaeration efficiency.
The APV WI+ centrifugal pump is used to ensure pumping of high
viscous products under vacuum. The APV WI+ pump is equipped
with an APV – Universal inducer acting as a helical screw pump
mounted to the pump shaft in front of the impeller, which reduces
the risk of cavitation especially when pumping high viscous prod-
ucts. The air content can be reduced to as low as 0.5 ppm oxygen.
The APV Parasol Deaerator is shown in Fig. 20.
Extended shelf life/ESLIn many parts of the world the production of fresh milk presents
a problem in regard to keeping quality. This is due to inadequate
cold chains, poor raw material and/or insufficient process and
filling technology. Until recently, the only solution has been to
produce UHT milk with a shelf life of 3 to 6 months at ambient
temperature. In order to try to improve the shelf life of ordinary
pasteurised milk, various attempts have been made to increase
pasteurisation temperature and this led to the extended shelf life
concept as referred to earlier in this publication.
SPX FLOW has in cooperation with Elopak developed the Pure-
LacTM concept, which in a systematic way attacks the challenge
of improving milk quality for the consumer.
TH E PU R ELAC TM PROCE SS
Based on investigations of consumer requirements and the
present market conditions in a large number of countries the
objective of Pure-LacTM was defined as follows:
• A sensory quality equal to or better than pasteurised products
• A “real life” distribution temperature of neither 5°C, nor 7°C but 10°C
• A prolonged shelf life corresponding to 14 to 45 days at 10°C
depending on filling methods and raw milk quality
• A method to accommodate changes in purchasing patterns of
the consumer
• An improved method for distribution of niche products
• To cover the complete milk product range, i.e. milk, creams,
desserts, ice cream mix, etc.
• To provide tailored packaging concepts designed to give maximum
protection using minimum but adequate packaging solutions
Having reviewed the range of “cold technologies” available it be-
came obvious that most of them were only suited for white milk.
Furthermore the actual microbiological reduction rate for some
of the processes were inadequate to provide sufficient safety for
shelf life of more than 14 days at 10°C.
Table 3 is a comparison between various processes and their
ability to reduce bacteria and various types of spores. Using the
data in Table 3 on a milk containing 10 to 100 spores/ml in the
raw milk out of which 10 percent are psychrotrophic spores, the
following result is achieved:
• Microfiltration, log 3 reduction
1 to 10 psychrotrophic spores per litre in the final product
Every carton is a potential risk
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 26 27/06/2018 07.39
Fig. 21: APV Factory Expert
27
Long Life Dairy, Food and Beverage Products
• Pure-LacTM, log 8 reduction
< 1 psychrotrophic spore per 10.000 litre in the final product
Large safety margin and excellent quality buffer
Bacteria-removing centrifuges are also used to improve the
quality of drinking milk. As shown in Table 3 on page 26 the
decimal reduction of bacteria and spores is less efficient than
for microfiltration. By reducing the throughput to half of the
nominal capacity or by double centrifugation the reduction
is improved by at least one decimal, which brings it closer to
microfiltration. However, double centrifugation increases the
investment and operating costs considerably, and this combined
with the loss of milk in the bacterial concentrate in the order of
1 to 6% reduces the attractiveness of using bacteria removing
centrifuges to extend the shelf life of milk.
The basis for the process is the infusion technology as de-
scribed. Several years of research and development have
resulted in a technology, which provides an extremely gentle
heating to a temperature of 130 to145°C in less than 1 second.
The rate of heating is very fast in the order of 500 to 600°C/s
providing all the benefits previously described.
With a combination of this process technology, the appropriate fill-
ing technology and a suitable carton it is possible to produce and
guarantee products with as good a taste and flavour as pasteurised
milk, having a shelf life up to 45 days at a storage temperature of
10°C. For comparison the same milk pasteurised at 72°C would have
a shelf life of 1 to 2 days under the same storage conditions, while it
would keep fresh for 10 days at a storage temperature of 4°C.
Comparison between different systemsAs illustrated in the presentation of the various technologies
there is a wide choice and there are several considerations to
be made before the final decision is taken. SPX FLOW’s team of
experts is available to advise on selecting the most appropriate
technology for each specific requirement.
Table 4 on page 28 provides a rough guideline of the advan-
tages and disadvantages of different technologies in relation to
a variety of products. This is meant as a guideline to make the
right choice, which in many cases may be obvious while in other
cases more difficult. As mentioned in the section on the APV Pi-
lot Plant this provides a tool for testing different products using
different heating technologies, and this may sometimes become
necessary to ensure the correct choice.
Process controlsOne of the most important aspects of an aseptic plant is the
process control system. It must continuously monitor all process
parameters and take reliable corrective action in case of a failure.
Today all of SPX FLOW’s UHT systems operate under a PLC (Pro-
grammable Logic Controller) or a DCS (Distributed Control System)
based on the world leading brands, providing the best possible
repeatability and reliability in the operation. This means consistent
product quality, package after package, day after day. Human error
is minimised and greater production efficiency is achieved.
There are many systems, which are capable of successfully
operating an aseptic plant. However, when it comes to choosing
the right concept for the process control system there are ad-
ditional factors to take into consideration. Such factors include
hardware durability and availability, service from the supplier and
communication ability with surrounding control systems in the
plant. The operating personnel’s familiarity with a particular con-
trol system is also important, and there may be special regula-
tory codes, which require adaptation of control systems.
The world leading process technology – a result of many years’
development and experience – is built into our software packag-
es. The control system has already been tested in many similar
applications and they are always pretested prior to delivery.
Fig. 21 shows an SPX FLOW produc-
tion management system: The APV
Factorty Expert Concept.
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 27 27/06/2018 07.39
Table 4: Comparison between the most commonly used processing systems rated on a scale from 1 to 5:
28
Long Life Dairy, Food and Beverage Products
PLATE STE R I LI S E R
TU B U LAR STE R I LI S E R
STEAM I N FUS ION
STE R I LI S E R
STEAM I NJ ECTION
STE R I LI S E R
H IG H H EAT I N FUS ION
STE R I LI S E R
I N STANT I N FUS ION PASTE U R
I S E R
SS H E STE R I LI S E R
M I LK
LOW C O ST 1 2 5 4 3 5 5
H I G H Q UALITY 3 3 1 2 2 1 5
P O O R Q UALITY 4 2 1 2 2 1 5
H EAT R E S I STANT S P O R E S 3 3 2 2 1 5 5
F LAVO U R E D M I LK
FO U LI N G P R O D U CT (C H O C O LATE) 3 2 1 2 2 1 5
VO LATI LE AR O MA 1 1 3 3 2 3 5
D I F F I C U LT TO STE R I L I S E (C O C OA) 3 2 1 1 1 3 5
S E N S IT IVE C O LO U R 3 3 1 2 2 1 5
C R EAM
WH I P P I N G C R EAM 3 3 1 2 2 1 5
STAB I L I S E D D E S S E RTS 4 3 1 2 2 1 5
C O O K E D C R EAM 2 2 1 2 2 4 5
C O F F E E WH ITE N E R S
M I LK-BAS E D 1 1 2 3 1 3 5
VEGETABLE OIL-BASED (EMULSIFIED) 1 1 2 3 1 3 5
FO U LI N G / H I G H P R OTE I N C O NTE NT AN D STAB I L I S E R 4 4 2 3 4 1 5
J U I C E
W ITH P U LP, F I B R E S >1 M M 5 1 5 5 5 5 5
W ITH P U LP, F I B R E S <1 M M 3 1 5 5 5 5 5
W ITH O UT P U LP AN D F I B R E S 1 1 5 5 5 5 5
YO G H U RT 1 1 4 4 4 4 4
Q UAR K 5 5 4 4 5 3 1
BABY FO O D 3 3 1 2 3 1 1
M I LK C O N C E NTRATE 4 4 2 3 4 1 2
P U D D I N G S
STAB I L I S E D, H I G H S O LI D S, STAR C H 5 4 2 4 4 1 3
STAB I L I S E D W ITH CAR RAG E E NAN 3 3 2 3 3 2 3
S OY M I LK
LOW C O ST 1 2 5 4 5 5 5
H I G H Q UALITY 3 3 1 2 1 1 5
P O O R Q UALITY RAW MATE R IAL 4 3 1 2 2 1 5
C O F F E E AN D TEA 1 1 4 4 4 4 5
S O U P S AN D SAU C E S 5 2 4 4 5 5 1
OTH E R C O N S I D E RATI O N S
H EAT STAB I L ITY 3 3 1 2 3 1 3
AS E PTI C P R O D U CT 1 1 1 1 1 4 1
F LE X I B I L ITY 3 3 1 2 1 1 1
MAI NTE NAN C E 2 1 2 2 2 2 3
1 = E XC E LLE NT 2 = G O O D 3 = AC C E PTAB LE 4 = P O S S I B LE 5 = N OT R E C O M M E N D E D
APV_Long_Life_Dairy_Food_22000_08_07_2018_GB.indd 28 27/06/2018 07.39
29
Long Life Dairy, Food and Beverage Products
In order to preserve their high micro-biological quality, asepti-
cally processed products must be packed aseptically. Even at
room temperature, the packaged product then has a shelf life of
several months.
In aseptic filling and packaging, the aseptically processed product
is filled under aseptic conditions into commercially sterile contain-
ers, which are either preformed or formed in conjunction with
the filling operation. After the filling has been completed, the
containers are hermetically sealed. The resultant packages are
liquid-proof and exclude air, light and bacteria. This method of pro-
cessing and packaging allows for the use of paperboard, plastic
containers or pouches as packaging materials, and eliminates the
need for cans and energy inefficient retort heating systems.
The choice of packaging concept depends on product type, unit
cost and customer preference. Environmental concerns, volume
of waste and the possibility of recycling of packaging material
become increasingly important depending however, on the stage
of development of the community.
SPX FLOW is not a manufacturer of packaging systems but co-
operates with all companies in the packaging sector and is able to
supply the appropriate solution for complete and turnkey systems.
With an SPX FLOW system, customers are assured of a com-
plete aseptic processing line producing high quality products
packed for the specific market in the most cost-effective way.
New products are developed more rapidly than ever before in or-
der to satisfy demands in the consumer market. Simultaneously
the life-cycle of the individual products tends to shorten. These
conditions force the producers to intensify and accelerate prod-
uct development. Capabilities in aseptic processing and related
disciplines enable SPX FLOW to support customers to develop
new value added products at the highest possible speed.
This can be achieved through product testing in the test and
development centres around the world or by means of an APV
Pilot Plant installed at the customers site.
SPX FLOW is keen to work in partnership with customers in
order to accelerate the product development process.
It is the objective of SPX FLOW to deliver innovation, quality and
reliability to the dairy, food and beverage industry and in this way
contribute to safe and high quality products for the consumer.
Product developmentFilling and packaging
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Long Life Dairy, Food and Beverage Products
ABOUT S PX FLOW
SPX FLOW, based in Charlotte, North Carolina, USA, has an
annual turnover of approximately 5 billion USD 16,000 employ-
ees, an extensive product portfolio and a strong financial base,
well-geared for growth.
SPX FLOW is serving many industries including the dairy, food,
beverage, brewery and personal care industries. SPX FLOW has
brought together a number of highly recognised global brands,
including APV, Anhydro, Gerstenberg Schröder, which form the
back bone of our food & beverage offerings and activities.
CUSTOM E RCE NTE R E D SOLUTION S
With a strong synergy between the SPX FLOW brands as well
as a solid knowledge and innovation platform, SPX FLOW can
offer our customers a broad range of products, systems and in-
novative solutions as well as services reflecting the industry and
consumer trends such as:
• New innovative products for specific consumer groups
• Better utilisation of best from nature for healthy and natural
products and enhanced functional properties.
• Increased food safety, productivity and sustainably processes
whilst “return best to nature”.
ABOUT TH E APV B RAN D
Part of SPX FLOW Corporation and operating worldwide
with employees in over 35 countries, the APV brand provides
manufacturing solutions and process equipment to customers in
the food, dairy, beverage, brewing, healthcare, power, chemical,
marine, biotechnical and petrochemical industries.
The APV brand provides a unique range of highly functional
solutions and products that address key business drivers. APV
bases its solutions on advanced technology products including
pumps, valves, homogenisers and heat exchangers, as well as
production efficiency experience, development expertise, main-
tenance management and regulatory compliance.
About SPX FLOW
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Long Life Dairy, Food and Beverage Products
WE AR E EASY TO G ET I N TOUCH WITH I F YOU WOU LD LI KE TO KNOW MOR E ABOUT HOW WE
CAN H E LP YOU. WE CAN ASS I ST YOU I N TH E FOLLOWI NG WAYS:
• General advice and guidance in connection with your test planning
• Suggestions of plant and equipment most suited to your purpose
• Booking of test facilities and, if required, our experts and technicians
CONTACT US TODAY AT
SPX FLOW
E-mail: ft.enquiries@spxflow.com
Phone: +45 70 278 278
www.spxflow.com
We look forward to hearing from you.
Contact Us
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SPX FLOW reserves the right to incorporate our latest design and material changes without notice or obligation.
Design features, materials of construction and dimensional data, as described in this bulletin, are provided for your information only and should not be relied upon unless
confirmed in writing. Please contact your local sales representative for product availability in your region. For more information visit www.spxflow.com.
The green “>”, Anhydro, APV, Waukesha Cherry-Burrell, and Seital Separation Technology are registered trademarks of SPX FLOW, Inc.
APV-22000-GB VERSION 08/2018 ISSUED 07/2018
COPYRIGHT © 2018 SPX FLOW, Inc.
S PX FLOW, D E N MAR K
Pasteursvej 1
8600 Silkeborg
Denmark
P: +45 70 278 278
F: +45 70 278 330
E: ft.dk.silkeborg@spxflow.com
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