Printed Intelligence in Packaging
Eero HurmeVTT Technical Reseach Centre of Finland
Session 3, paper 7642
Paper 7642 Eero Hurme 2
Contents• Background
– Product safety and convenience issues for packed food
– Technology overview
• Development of package leak indicators– Visual detection– Automatic optical detection
• Future prospects
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Background studies• Internal research programme 2002 - 2006 on Intelligent
products and Systems– Active, Communicating Packaging Systems
(consumer packages)• Printed low cost diagnostic indicators• Optical coding systems• Printable conductive wiring, thin film indicators
• Sustainpack EU -project 2004 - 2008– Printed rH sensors and optical detection methods
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Innovative packages through ages (for food safety)
functional packagesMA-packages
aseptic packagesretorted plastic pouches
sterilised hermetic bottleswine containers
water submergeleaves
Stone Age .... 1800 1900 2000
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Intelligent packaging systems
WAY OF ACTION
• Printed label (e.g. ingredients, best before, instructions)
• Colour changing indicator label/print
• Electronic tags
FUNCTION
• Monitoring the conditions of package/packedfood
• Storage of information & communication
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Intelligent packaging systems Indicator Principle/
reagentsGivesinformationabout
Application
Time-temperatureindicators(external)
MechanicalChemicalEnzymatic
Storageconditions
Foods stored under chilledand frozen conditions
Oxygenindicators(internal)
Redox dyespH dyesEnzymes
Storageconditions
Package leak
Foods stored in MApackages
Carbondioxideindicator(internal)
Chemical Storageconditions
Package leak
MA or CA food packaging
Microbialgrowthindicators(internal)
pH dyesAll dyes reactingwith certainmetabolites(volatiles or non-volatiles)
Microbialquality offood
Perishable foods
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Package leakage indication systems
BACKGROUND• New materials, new product types
leaking seals– possible hazards in safety
• Demonstrations of integrity requirements for consumer packages– Development of in-line non-
destructive leak testers– Development of package indicators
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Critical leakage diameter in consumer packages
Growth of E. aerogenes in biotested packages
0
20
40
60
80
100
0 7-9 10-12 13-15 16-18 19-21 22-24
Microhole diameter (µm)
Con
tam
inat
ed (%
)
50 347
11
21
14
47
0
20
40
60
80
100
0 7-9 10-12 13-15 16-18 19-21 22-24
Microhole diameter (µm)
Con
tam
inat
ed (%
)
50 8 10 33
54
13 20
10
Aseptic cup , lid 100 µm Retort tray, lid 220 µm
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Package leakage vs.microbiological quality
0
1
2
3
4
5
6
7
8
9
10
0 5 10 15 20 25
time (d)
PCA
(log
CFU
/g)
C8, PCACL8, PCAC5, PCACL5, PCA
Leaking package
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Package leakage vs.indicator colour change
40
45
50
55
60
65
70
75
80
85
90
0 5 10 15 20 25
time (d)
L-va
lue OS8
OSL8OS5OSL5
Leaking package
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Ink- jet inks for Indicators• Low cost• Clearly visible colour reaction• Irreversible colour change preferred• Stabile (time, temperature, moisture)• Suitable for food contact (legislation)• Physical properties;
– low viscosity, typically below 20 mPa·s– surface tension/wetting behaviour of fluid and nozzle
material → spray formation • Moisture often important in colour development →
water-based inks → binders and surface tratments to improve the adhesion.
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Printed package leakage (O2) indicator
• Visual and/or optically readable, low cost
– for sterilised shelf stable products (indicator activated by heat). Based on indigo colourant
– for fast moving consumer goods (indicator activated by volatile reducing agent, e.g. ammonia). Based on redox dye
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Printed package leakage (O2) indicator
• Application areas– Tamper-evidence of
hermetically sealed food/pharmaceutical/cosmetic packages
– Evaluation of use-by date in opened package at home
– Evaluation of remaining shelf-life of packed product
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Demo: Printed “Use-by” Indicator
Intact Opened48
HO
UR
S
2
HO
UR
S
• Printing: flexo (can be ink-jet)just before packaging
• Package conditions: 100% N2, rH 100%, O2 scavenger, 200mL plastic tray
• The “clock” started when the package was opened
• The rate of the colour changecan be tailored: reducing agents/compsition/protective layers
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OPTICAL DETECTIONMobile camera phone
• DEMO: The software detects the square from the focus area → the colour change is recognised
• → information can be used for judging whether the food is fresh or whether the package has been opened/tampered
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Freshness indicators
• Volatile compounds produced in microbial spoilage in – perishable products (meat,
fish, poultry, fresh-cuts,ready-to-eat meals)
– metabolites causing pH change, nitrogen compounds (e.g. volatile & biogenic amines), sulphuriccompounds,
HUMIDITY
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Freshness indicators
METABOLITES• H2S• CO2
• SO2
• NH4
• amines • diacetyl• organic acids • ethanol • microbial toxins
0
50
100
150
200
250
0 2 4 6 8 10
PCA (cfu/g)
tyra
min
e (p
pm)
Smolander, VTT
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Approval of indicators:Retailers attitudes
Smolander, VTT, 2004 0% 20% 40% 60% 80% 100%
LI / retailer
LI / consumer
FI / retailer
FI / consumer
TTI / retailer
TTI / consumer
improvenot changedecline
Quality and safety of the food product would...
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Printed Intelligence• Electronic, bio, chemical, optic,
optoelectronic etc. functionalities created and manufactured by printing like roll-to-roll methods.
• Cost efficient manufacturing, integration & embedding of simple intelligence everywhere.
• Filling the "gap" between traditional paper, printing and ICT/electronics industry products, towards applications like sensors, electronics and bioactive paper on large areas, tag and code technologies, …
Research results in commercialisation phase
20
Inkbyte®Printed Digital
Content
Raflatac® Pro Label
Hydrogen sulphideindicator label
UpCode™Optical code
solutions for mobile users
Roll-to-roll hotembossed gratings
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Acknowledgments• Senior Research Scientist Thea Sipiläinen-Malm• Senior Research Scientist Jali Heilmann• Research Scientist Liisa Hakola• Senior Research Scientist Maria Smolander
Further material• Bioactive paper and fibre products. Patent and literary
survey”, 83 p. VTT Working Papers 51 (2006).• www.vtt.fi/proj/cpi/index.jsp?lang=en