Laboratories for Small Brewers
Kevin Mutch Peripatetic Brewer 11 April 19 Topics
Product consistency
Sample Plan
Product Specification
Product testing In-process Post-process
Equipment Required Methodologies Product Consistency
Consumers need consistent product Establish, measure for comparison, set of process and product specifications Take corrective action if process or product ‘out of specification’ Measuring instrument tolerance Raw materials Sampling errors Specification and tolerances i.e. Range Sampling Schedule Specifying where, how and frequency of sampling Product Sample Plan Sample Plan
Key measurements taken without exception, across whole process – too late if quality issues come from customers
Record and present graphically – look at trends, compare MoM/YoY Example of Sample Plan
Stage Frequency Notes Stage Frequency Notes
Raw & Packaging Each delivery Frequency Fermented beer Each vessel Monitor Materials depends on & beer ready for quality/prepare supplier filtration for corrective performance & action reliability Brewhouse Each gyle Corrective action Beer ready for Each vessel Confirm operations taken quickly packaging compliance & suitability for package & consumption Unfermented Each gyle Corrective action Packaged beer Each batch Monitor packaging wort taken quickly performance Yeast Each batch for Only select good Plant Specified Monitor cleaning pitching yeast vessels per performance week Fermentation Each vessel Process control Cleaning Specified Ensure plant is Twice a day materials samples per cleaned effectively week Product and Process Specifications
Parameter Relevance ABV Product strength & value to customer Degree of consumer intoxication Original & Present Gravities Product strength & value to customer Indicates flavour strength pH Mash & wort pH affects enzyme performance Wort & beer pH affects hop utilisation & bitterness Wort & beer pH affects microbial growth Beer pH affect flavour Variable pH affects flavour Beer Colour Immediately perceived by consumer Beer Bitterness Strong flavour effect Product and Process Specifications
Parameter Relevance Trace flavour compounds - Fermentation by-products give beer its flavour Diacetyl, DMS, Acetaldehyde, Esters Balance ensures ‘trueness to type’ Excess will cause flavour problems Dissolved oxygen Promotes good yeast growth ergo good fermentation Oxidation in beer – stale, wet cardboard Unstable – hazes in packaged beer Dissolved carbon dioxide Sparkling characteristic of beer – head High levels – fob, dispense issues Dissolved nitrogen Foam stability, cling, flavour inhibition Beer Flavour - Why product is consumed Trueness to type Consumer expectation Product and Process Specifications
Parameter Relevance Clarity - Consumers expectation – attractive if ‘bright’ Haze, Potential haze Cloudy beer – poor quality, contamination, infection? Head stability - Consumer expectation – foamy head, cling to glass Foam, Cling sides Sterility Microbial contamination – most destructive defect Wild yeasts, moulds, bacteria grow readily in beer Effects 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 used Extraction process efficiency Wort colour Amount of coloured material used Degree of wort boiling Wort pH Mash & wort pH Brewing water quality Liquor treatment Malt quality Adjunct type and usage rates Wort fermentability Enzymic activity affected by mash conditions – time, temperature & pH Wort attenuation limit Fermentability of raw materials & adjuncts Wort sterility Wort chiller, wort mains, FVs Pitching Yeast Analysis
Parameter Determining factors
Microbial contamination Contamination from the plant Previous generation infection Yeast viability Age of the yeast (% dead cells) Condition of the yeast Yeast vitality Health pf previous generation Fermentation Operations Parameter Determining factors ABV Fermentation degree/efficiency Final gravity (FG) OG Beer pH Wort pH Fermentation degree/efficiency Beer colour Wort colour Bitterness Brewhouse hop addition & utilisation Yeast counts Strain/flocculation characteristics - cells in suspension Cropping operation Beer flavour Brewhouse and fermentation operations Raw material quality and usage rates Contamination Beer sterility Wort sterility Yeast purity Maturation/Conditioning Operations
As previous slide plus
Parameter Determining factors
Diacetyl Maturation time and temperature
Dissolved oxygen Transfer procedure Air content of vessel prior to fill
Dissolved carbon dioxide Degree of fermentation Vessel back pressure at fill
Beer sterility Fermented beer Transfer mains Maturation vessel Bright Beer Production and Filtration Operations
As previous slide plus
Parameter Determining factors ABV Filtration/liquor flush operations FG Bitterness Mature beer bitterness Bitterness loss on filtration Dissolved oxygen Filtration performance Dissolved carbon dioxide Mature beer content Content trimming during filtration Clarity Maturation time & temperature Filtration performance Stabilisation Packaging
As previous slide plus
Parameter Determining factor Air in headspace Packaging performance Fill level Packaging performance Label quality Packaging performance, labeller Label stock quality
Crown quality Packaging performance, crowner Crown stock quality
Can print quality Can stock quality
Canseamquality Packagingperformance,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 Whendidithappen? Checkpreviousresults What else was happening? Check raw materials Possible/likely cause? New batch of raw materials What can be done? Current issue – blend gyles Future – amend recipe change supplier? Product Specification Sheet Example – Brewhouse specification
Parameter Addition Rate/Specification & Range Comments
1. Liquor Treatment: To achieve Product Ionic Specification: Cl=403ppm, NaCl & CaSO4 added to MV Gypsum (Kg/100Hl) SO4=246ppm, K=520ppm, Na=190ppm, Sodium Chloride (Kg/100Hl) Mg=55ppm, Ca=60ppm min
2. Mash Grist: (As % Extract)
Plae Ale Malt 88.3 Crystal Malt 1.9
3. Mash Additions: B Glucanase l/tonne malt As required Optimised to suit malt performance
3. Hop Grist: Where added
Variety 1 Pellet hops to give target bitterness of 28 EBU in 1) Copper final pack Dry Hops Variety 2 only 2) Dry – 2 oz/brl Example – Process Specifications Parameter 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 dependent Sacharification Stand °C Time of temp rise (mins) Sacharification Stand (mins) 60 mins Or until starch -ve Raise to Run-off °C 76 =/- 1 Sparge Liquor: Total Liquor : Grist: Target 4 l/kg Temperature (max) 76 Run Off: Weak wort cut off PG Last Runnings PG as ° 1004 Boiling: Pre-boil temp profile Temperature >95°C Evaporation Rate %: Target 8 Cu up pH= 5-5.3 Min 6 Cu cast pH= 4.9-5.2 Max 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++ Collectiongravity 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 at Hold at 21 VDK Stand - Temp Time Cool to °C 6 - 8 C cask Cooling Rate °C/Hr FV Residence Targets : RG target 8.5 Time to half gravity Cycle Time target 4 days, range 3 - 5.0 Time to racking gravity 3 Days days Time to Cooling On 4 Days
Total Residence 7 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 6C
Yeast count 1 x 106 / ml
Cask Racking:
Beer received into Draught Racking Tank for final checks.
DO spec 0.5 ppm max.
CO2 range 0.9-1.1 volumes
Isinglass finings added to cask at rack 3.25 pints/brl Typical rate
Casks dry-hopped 2 oz/brl Example – In Package Product Specification PARAMETER SPECIFICATION AQL RQL* OG 1037 +/- 0.1 +/-0.2 PG 1008.4 +/- 0.1 +/-0.2 FG 1007.4 FR 1.0 max % Alc v/v 3.7 0.1 0.2 Colour, EBC 14.5 +/- 0.5 =/-0.75 Haze MU'S Bitterness, EBU 28 +/- 1 +/- 2 Bitterness ppm iso by HPLC 28 VDK ppm 0.07 max YEAST COUNT at rack 1 million cells/ml +/- 0.25 x 106 +/- 0.5 x 106 CO2 (Vols) - Keg - Tank - Bottle - Can - Cask 1.0 D.O. ppm T.I.P.O ppm HRV secs - Rudin - Nibem Chloride 403 Sulphate 246 pH 3.9 Total Carbohydrate g/100ml Calorific Value Kcals/100ml P.U's Nitrogen ppm Laboratory Analyses What do you need for the analyses? Minimum Required Laboratory Equipment - General
Item <25brl/wk >26brl/wk Temperature probes Y Y Record/confirm process temps, NOT GLASS long & small probes THERMOMETERS 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 all types of items. Production balance Y Y Check weigh full product containers Minimum Required Laboratory Equipment – Physical & Chemical Item <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-Visible Y Beer bitterness & colour, diacetyl, FAN, spectrophotometer 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 presence differential staining ATP luminometer Y Y Surface Hygiene Using ATP Bioluminescence
Descriptive analysis Y Y Descriptive Analysis Training Y Y Selection and training of assessors, flavour terminology and reference standards Temperature Probes
How many?
Master probe
Calibration check – how, when? 0oC - ice 100oC - kettle Record findings pH meters
How many?
Master meter?
Calibration check – how, when? pH 4, 7, 10 Probe care!
Record findings Gravity Refractometer – area of use? Calibration check – how, when? Sample chamber care! Record findings
Saccharometers - how many? HMRC acceptable ranges?
*Use a suitably calibrated saccharometer adjusted for the temperature of the representative sample Precision 10° or 20° range saccharometers (305mm long) Excise Notice 226: Beer Duty ABV
Distillation method for alcohol determination Remove known volume (measured at 20°C) of beer, degas and clarify by filtration Remove the alcohol by distilling the sample and collect the distillate Make up the volume of the distillate with distilled water to that of the original sample measured at 20°C Measure the density of the sample Calculate the content of alcohol by reading the value from the official tables Dissolved gasses
CO2 meters - areas of use? Calibration checks – how, when?
Corning 965 & 50 μl pipette Sample 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 for samples Balances
Calibrate – how , when
Laboratory - 0 - 2.0kg - Small pack volumes
Plant - 0 - 100kg - Raw materials - Large pack volumes Microscope Binocular microscope x40 & x100 objective lenses TV link to screen? Visual check Yeast counts Keep clean! Heamocytometer
Methylene blue stain in yeast suspension Wet Yeast Pitching calculation
Usual to use centrifuge Spin known weight slurry Pour off barm ale Weigh packed yeast
The relationship between cell count and spun solids is given approximately as 10 million cells per ml = 2.5 - 3.0 g/litre spun wet yeast Microbial Contamination – Electron Micrographs
Biofilm Colonised SS surface Microbial Presence Testing - CIP
ATP bioluminescence Swabs Records Haze/Turbidity
Haze meter Imhoff cones Hot & cold breaks Questions?