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Laboratories for Small Brewers Kevin Mutch Peripatetic Brewer 11 April 19
Laboratories for Small Brewers
Kevin Mutch
Peripatetic Brewer
11 April 19
Topics
Product consistency
Sample Plan
Product Specification
Product testingIn-process
Post-process
Equipment RequiredMethodologies
Product Consistency
Consumers need consistent product
Establish, measure for comparison, set of process andproduct specifications
Take corrective action if process or product ‘out ofspecification’
Measuring instrument tolerance
Raw materials
Sampling errors
Specification and tolerances i.e. Range
Sampling ScheduleSpecifying where, how and frequency of sampling
Product Sample Plan
Sample Plan
Key measurements taken without exception, across wholeprocess
– too late if quality issues come from customers
Record and present graphically– look at trends, compare MoM/YoY
Example of Sample PlanStage Frequency Notes Stage Frequency Notes
Raw & PackagingMaterials
Each delivery Frequencydepends onsupplierperformance &reliability
Fermented beer& beer ready forfiltration
Each vessel Monitorquality/preparefor correctiveaction
Brewhouseoperations
Each gyle Corrective actiontaken quickly
Beer ready forpackaging
Each vessel Confirmcompliance &suitability forpackage &consumption
Unfermentedwort
Each gyle Corrective actiontaken quickly
Packaged beer Each batch Monitor packagingperformance
Yeast Each batch forpitching
Only select goodyeast
Plant Specifiedvessels perweek
Monitor cleaningperformance
Fermentation Each vesselTwice a day
Process control Cleaningmaterials
Specifiedsamples perweek
Ensure plant iscleaned effectively
Product and Process Specifications
Parameter Relevance
ABV Product strength & value to customerDegree of consumer intoxication
Original & Present Gravities Product strength & value to customerIndicates flavour strength
pH Mash & wort pH affects enzyme performanceWort & beer pH affects hop utilisation & bitternessWort & beer pH affects microbial growthBeer pH affect flavourVariable pH affects flavour
Beer Colour Immediately perceived by consumer
Beer Bitterness Strong flavour effect
Product and Process Specifications
Parameter Relevance
Trace flavour compounds -Diacetyl, DMS, Acetaldehyde, Esters
Fermentation by-products give beer its flavourBalance ensures ‘trueness to type’Excess will cause flavour problems
Dissolved oxygen Promotes good yeast growth ergo good fermentationOxidation in beer – stale, wet cardboardUnstable – hazes in packaged beer
Dissolved carbon dioxide Sparkling characteristic of beer – headHigh levels – fob, dispense issues
Dissolved nitrogen Foam stability, cling, flavour inhibition
Beer Flavour -Trueness to type
Why product is consumedConsumer expectation
Product and Process Specifications
Parameter Relevance
Clarity -Haze, Potential haze
Consumers expectation – attractive if ‘bright’Cloudy beer – poor quality, contamination, infection?
Head stability -Foam, Cling
Consumer expectation – foamy head, cling to glasssides
Sterility Microbial contamination – most destructive defectWild yeasts, moulds, bacteria grow readily in beerEffects flavour, aroma, clarity – undrinkable?Small contaminations – growth rate – major issue
Wort Production and Brewhouse Operations
Parameter Determining factors
Wort specific gravity Amount of malt and water usedExtraction process efficiency
Wort colour Amount of coloured material usedDegree of wort boilingWort pH
Mash & wort pH Brewing water qualityLiquor treatmentMalt qualityAdjunct type and usage rates
Wort fermentability
Wort attenuation limit
Enzymic activity affected by mash conditions –time, temperature & pHFermentability of raw materials & adjuncts
Wort sterility Wort chiller, wort mains, FVs
Pitching Yeast Analysis
Parameter Determining factors
Microbial contamination Contamination from the plantPrevious generation infection
Yeast viability(% dead cells)
Age of the yeastCondition of the yeast
Yeast vitality Health pf previous generation
Fermentation OperationsParameter Determining factors
ABVFinal gravity (FG)
Fermentation degree/efficiencyOG
Beer pH Wort pHFermentation degree/efficiency
Beer colour Wort colour
Bitterness Brewhouse hop addition & utilisation
Yeast counts- cells in suspension
Strain/flocculation characteristicsCropping operation
Beer flavour Brewhouse and fermentation operationsRaw material quality and usage ratesContamination
Beer sterility Wort sterilityYeast purity
Maturation/Conditioning Operations
As previous slide plus
Parameter Determining factors
Diacetyl Maturation time and temperature
Dissolved oxygen Transfer procedureAir content of vessel prior to fill
Dissolved carbon dioxide Degree of fermentationVessel back pressure at fill
Beer sterility Fermented beerTransfer mainsMaturation vessel
Bright Beer Production and Filtration Operations
As previous slide plus
Parameter Determining factors
ABVFG
Filtration/liquor flush operations
Bitterness Mature beer bitternessBitterness loss on filtration
Dissolved oxygen Filtration performance
Dissolved carbon dioxide Mature beer contentContent trimming during filtration
Clarity Maturation time & temperatureFiltration performanceStabilisation
Packaging
As previous slide plus
Parameter Determining factor
Air in headspace Packaging performance
Fill level Packaging performance
Label quality Packaging performance, labellerLabel stock quality
Crown quality Packaging performance, crownerCrown stock quality
Can print quality Can stock quality
Can seam quality Packaging performance, seamer
Out of Specification Actions
1 Current problem
2 Prevention of reoccurrence-who, what, when, where, why & how
Real? Results correct?
Extent of issue, other beers affected?
When, where did it happen? What else happening at the time?
Possible causes? Likely causes?
What can be done about it?
Example Investigation
OOS - High colour
Investigation Action
Correct results? Recheck analysis
Issue extent? Check other beers
When did it happen? Check previous results
What else was happening? Check raw materials
Possible/likely cause? New batch of raw materials
What can be done? Current issue – blend gylesFuture – amend recipe
change supplier?
Product Specification Sheet
Example – Brewhouse specification
Parameter Addition Rate/Specification & Range Comments
1. Liquor Treatment:Gypsum (Kg/100Hl)
Sodium Chloride (Kg/100Hl)
To achieve Product Ionic Specification: Cl=403ppm,SO4=246ppm, K=520ppm, Na=190ppm,Mg=55ppm, Ca=60ppm min
NaCl & CaSO4 added to MV
2. Mash Grist: (As % Extract)
Plae Ale MaltCrystal Malt
88.31.9
3. Mash Additions:B Glucanase l/tonne malt As required Optimised to suit malt
performance
3. Hop Grist:
Variety 1
Dry Hops Variety 2 only
Pellet hops to give target bitterness of 28 EBU infinal pack
Where added
1) Copper
2) Dry – 2 oz/brl
Example – Process SpecificationsParameter Addition Rate/ Specification & Range Comments
Mashing:Mash Liquor:
Liquor : Grist - Target 2.6 l/kg(Hl : Tonnes) Range
Temperature Profile:Mashing Temperature °C 65 +/- 2 Variable and plant dependentSacharification Stand °C
Time of temp rise (mins)
Sacharification Stand (mins) 60 mins Or until starch -veRaise to Run-off °C 76 =/- 1
Sparge Liquor:Total Liquor : Grist: Target 4 l/kgTemperature (max) 76
Run Off:Weak wort cut off PGLast Runnings PG as ° 1004
Boiling:Pre-boil temp profile Temperature >95°CEvaporation Rate %: Target 8 Cu up pH= 5-5.3
Min 6 Cu cast pH= 4.9-5.2Max 10 Typical FAN=120-140 at 1038
Boil Time (mins): Target 60 Apparent fermentability 84-90%Late Additions:
Copper Fining As required Added prior to cast and re-boil
Example - Process Specifications
Parameter Addition Rate/ Specification & Range Comments
Wort Cooling:
Fill time 20
Whirlpool Stand Time: As required
Target To achieve clarity
Run-off profile/time (trub out proceed) Trub to drain
Collection Temperature °C 16
Oxygenation ppm:
Target 18 Variable on fermentation performance
Range 15-22
Wort cooling additions Zinc sulphate Target 0.1 mg/l Z++
Collection gravity 1038.0
Collection time
No. of Brews/FV 1/2 Fermented in conical
Example - Yeast Specification
Parameter Addition Rate/ Specification & Range Comments
Pitching Details:
Yeast Type: Ale
Max. Generation No 15
Viability (% min) 85
Rate (million cells / ml):
Target 9 x 106
Max Range 7-10 x 106
Acid Wash: Yes if required
Acid Type Phosphoric
pH Target 2.1
pH range 2.0 – 2.2
Contact Time Target (mins)
Max 120
Example – Process Specification
Parameter Addition Rate/ Specification & Range Comments
Fermentation:
Profile Reference Number
Temperature Profile:Collection Temperature °C 16
First Rise to °C 21
Second Rise to °C atVDK Stand - Temp
Time
Hold at 21
Cool to °C 6 - 8 C cask
Cooling Rate °C/Hr
FV Residence Targets :Time to half gravityTime to racking gravityTime to Cooling On
Total Residence
3 Days4 Days
7 Days
RG target 8.5Cycle Time target 4 days, range 3 - 5.0
days
VDK Target, prior to cool as ppm N/A
Time to yeast crop
Rousing Regime Nil
Auxiliary Finings added post - skim
Fermenter Type conical
Example – Pre-packaging Specification
Parameter Addition Rate/ Specification & Range Comments
Cask Run-Down:
Run Down from FV to Racking Tank
Yeast count
6C
1 x 106 / ml
Cask Racking:
Beer received into Draught Racking Tank for final checks.
DO spec
CO2 range
Isinglass finings added to cask at rack
Casks dry-hopped
0.5 ppm max.
0.9-1.1 volumes
3.25 pints/brl
2 oz/brl
Typical rate
Example – In Package Product SpecificationPARAMETER SPECIFICATION AQL RQL*OGPGFGFR% Alc v/vColour, EBCHaze MU'SBitterness, EBUBitterness ppm iso by HPLCVDK ppmYEAST COUNT at rackCO2 (Vols)- Keg- Tank- Bottle- Can- CaskD.O. ppmT.I.P.O ppmHRV secs- Rudin- NibemChlorideSulphatepHTotal Carbohydrate g/100mlCalorific Value Kcals/100mlP.U'sNitrogen ppm
10371008.41007.41.0 max
3.714.5
2828
0.07 max1 million cells/ml
1.0
4032463.9
+/- 0.1+/- 0.1
0.1+/- 0.5
+/- 1
+/- 0.25 x 106
+/-0.2+/-0.2
0.2=/-0.75
+/- 2
+/- 0.5 x 106
Laboratory Analyses
What do you need for the analyses?
Minimum Required Laboratory Equipment - General
Item <25brl/wk >26brl/wk
Temperature probesNOT GLASSTHERMOMETERS
Y Y Record/confirm process temps,long & small probes
Refrigerator / cooler Y Y Sample storage, chemical storage
Wrist &/or table shaker Y Beer Bitterness
Centrifuge Y* Y Bitterness Units, Colour,*Yeast Solids % by Spin‐down
Stir plate / hot plate Y Degassing, chemical preparation
Titration burette Y Bitterness
Water bath Y Y Sample attemperation
Analytical balance Y Y Use in many methods for weighing alltypes of items.
Production balance Y Y Check weigh full product containers
Minimum Required Laboratory Equipment– Physical & ChemicalItem <25brl/wk >26brl/wk
Alcohol meter ? Alcohol determination
CO2 meter Y* Y Dissolved CO2 - * if kegging/small pack
Digital density meter ? Extract, specific gravities
Distillation equipment ? Alcohol determination, bitterness
Hydrometer Y Y Extract, specific gravities
Oxygen meter Y* Y O2 content - * if kegging/small pack
pH meter Y Y pH of source water, brewing liquor,wort, fermenting beer, fermented beer,packaged beer. CIP rinse waters
UV-Visiblespectrophotometer
Y Beer bitterness & colour, diacetyl, FAN,total polyphenols, wort colour
Haze meter Y Physical Stability
Minimum Required Laboratory Equipment– Microbiological & Sensory
Item <25brl/wk >26brl/wk
Microscope Y Y Yeast cell count, viability,morphology, bacterial presencedifferential staining
ATP luminometer Y Y Surface Hygiene Using ATPBioluminescence
Descriptive analysis Y Y Descriptive Analysis
Training Y Y Selection and training ofassessors, flavour terminologyand reference standards
Temperature Probes
How many?
Master probe
Calibration check – how, when?0oC - ice100oC - kettleRecord findings
pH meters
How many?
Master meter?
Calibration check – how, when?pH 4, 7, 10Probe care!
Record findings
Refractometer – area of use?Calibration check – how, when?Sample chamber care!Record findings
Saccharometers - how many?HMRC acceptable ranges?
*Use a suitably calibrated saccharometeradjusted for the temperature of therepresentative samplePrecision 10° or 20° rangesaccharometers (305mm long)
Gravity
Excise Notice 226: Beer Duty
ABV
Distillation method for alcohol determinationRemove known volume (measured at 20°C) of beer,degas and clarify by filtrationRemove the alcohol by distilling the sample and collectthe distillateMake up the volume of the distillate with distilled water tothat of the original sample measured at 20°CMeasure the density of the sampleCalculate the content of alcohol by reading the valuefrom the official tables
Dissolved gasses
CO2 meters - areas of use?Calibration checks – how, when?
Corning 965 & 50 μl pipetteSample volume check!Sample chamber care!
Total in pack CO2
‘Spike’ care
DO2
Probe care!
Colour
Lovibond Colourimeter
Calibration checks – how, when?
Cuvette size and care?
UV-Vis Spectrophotometer
Calibration checks – how, when?
Cuvette care?
Chemical reagents required forsamples
Balances
Calibrate – how , when
Laboratory- 0 - 2.0kg- Small pack volumes
Plant- 0 - 100kg- Raw materials- Large pack volumes
MicroscopeBinocular microscope x40 & x100 objective lensesTV link to screen?Visual checkYeast countsKeep clean!
Heamocytometer
Methylene blue stain in yeast suspension
Usual to use centrifugeSpin known weight slurryPour off barm aleWeigh packed yeast
The relationship betweencell count and spunsolids is givenapproximately as10 million cells per ml= 2.5 - 3.0 g/litre spunwet yeast
Wet Yeast Pitching calculation
Microbial Contamination – Electron Micrographs
Biofilm Colonised SS surface
Microbial Presence Testing - CIP
ATP bioluminescenceSwabsRecords
Haze/Turbidity
Imhoff conesHot & cold breaks
Haze meter
Questions?
