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 Materials Each delivery Frequency depends on supplier performance & reliability Fermented beer & beer ready for filtration Each vessel Monitor quality/prepare for corrective action Brewhouse operations Each gyle Corrective action taken quickly Beer ready for packaging Each vessel Confirm compliance & suitability for package & consumption Unfermented wort Each gyle Corrective action taken quickly Packaged beer Each batch Monitor packaging performance Yeast Each batch for pitching Only select good yeast Plant Specified vessels per week Monitor cleaning performance Fermentation Each vessel Twice a day Process control Cleaning materials Specified samples per week Ensure plant is cleaned effectively
Product and Process Specifications Parameter ABV Original & Present Gravities ph Beer Colour Beer Bitterness Relevance Product strength & value to customer Degree of consumer intoxication Product strength & value to customer Indicates flavour strength 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 Immediately perceived by consumer Strong flavour effect
Product and Process Specifications Parameter Trace flavour compounds - Diacetyl, DMS, Acetaldehyde, Esters Dissolved oxygen Dissolved carbon dioxide Dissolved nitrogen Beer Flavour - Trueness to type Relevance Fermentation by-products give beer its flavour Balance ensures trueness to type Excess will cause flavour problems Promotes good yeast growth ergo good fermentation Oxidation in beer stale, wet cardboard Unstable hazes in packaged beer Sparkling characteristic of beer head High levels fob, dispense issues Foam stability, cling, flavour inhibition Why product is consumed Consumer expectation
Product and Process Specifications Parameter Clarity - Haze, Potential haze Head stability - Foam, Cling Sterility Relevance Consumers expectation attractive if bright Cloudy beer poor quality, contamination, infection? Consumer expectation foamy head, cling to glass sides 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 Wort specific gravity Wort colour Mash & wort ph Wort fermentability Wort attenuation limit Wort sterility Determining factors Amount of malt and water used Extraction process efficiency Amount of coloured material used Degree of wort boiling Wort ph Brewing water quality Liquor treatment Malt quality Adjunct type and usage rates Enzymic activity affected by mash conditions time, temperature & ph Fermentability of raw materials & adjuncts Wort chiller, wort mains, FVs
Pitching Yeast Analysis Parameter Determining factors Microbial contamination Yeast viability (% dead cells) Yeast vitality Contamination from the plant Previous generation infection Age of the yeast Condition of the yeast Health pf previous generation
Fermentation Operations Parameter ABV Final gravity (FG) Beer ph Beer colour Bitterness Yeast counts - cells in suspension Beer flavour Beer sterility Determining factors Fermentation degree/efficiency OG Wort ph Fermentation degree/efficiency Wort colour Brewhouse hop addition & utilisation Strain/flocculation characteristics Cropping operation Brewhouse and fermentation operations Raw material quality and usage rates Contamination Wort sterility Yeast purity
Maturation/Conditioning Operations As previous slide plus Parameter Diacetyl Dissolved oxygen Dissolved carbon dioxide Beer sterility Determining factors Maturation time and temperature Transfer procedure Air content of vessel prior to fill Degree of fermentation Vessel back pressure at fill Fermented beer Transfer mains Maturation vessel
Bright Beer Production and Filtration Operations As previous slide plus Parameter ABV FG Bitterness Dissolved oxygen Dissolved carbon dioxide Clarity Determining factors Filtration/liquor flush operations Mature beer bitterness Bitterness loss on filtration Filtration performance Mature beer content Content trimming during filtration Maturation time & temperature Filtration performance Stabilisation
Packaging As previous slide plus Parameter Air in headspace Fill level Label quality Crown quality Can print quality Can seam quality Determining factor Packaging performance Packaging performance Packaging performance, labeller Label stock quality Packaging performance, crowner Crown stock quality Can stock 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 Correct results? Issue extent? When did it happen? What else was happening? Possible/likely cause? What can be done? Action Recheck analysis Check other beers Check previous results Check raw materials New batch of raw materials Current issue blend gyles Future amend recipe change supplier?
Product Specification Sheet
Example Brewhouse specification 1. Liquor Treatment: Gypsum Sodium Chloride Parameter Addition Rate/Specification & Range Comments (Kg/100Hl) (Kg/100Hl) To achieve Product Ionic Specification: Cl=403ppm, SO4=246ppm, K=520ppm, Na=190ppm, Mg=55ppm, Ca=60ppm min NaCl & CaSO 4 added to MV 2. Mash Grist: (As % Extract) Plae Ale Malt Crystal Malt 88.3 1.9 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 in final pack Where added 1) Copper 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++ 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 10 6 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 Cooling Rate C/Hr FV Residence Targets : Time to half gravity Time to racking gravity Time to Cooling On 6-8 C cask 3 Days 4 Days RG target 8.5 Cycle Time target 4 days, range 3-5.0 days Total Residence VDK Target, prior to cool as ppm Time to yeast crop Rousing Regime Auxiliary Finings added post - skim Fermenter Type 7 Days N/A Nil conical
Example Pre-packaging Specification Parameter Addition Rate/ Specification & Range Comments Cask Run-Down: Run Down from FV to Racking Tank Yeast count 6 C 1 x 10 6 / 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 Specification PARAMETER SPECIFICATION AQL RQL* OG PG FG FR % Alc v/v Colour, EBC Haze MU'S Bitterness, EBU Bitterness ppm iso by HPLC VDK ppm YEAST COUNT at rack CO2 (Vols) - Keg - Tank - Bottle - Can - Cask D.O. ppm T.I.P.O ppm HRV secs - Rudin - Nibem Chloride Sulphate ph Total Carbohydrate g/100ml Calorific Value Kcals/100ml P.U's Nitrogen ppm 1037 1008.4 1007.4 1.0 max 3.7 14.5 28 28 0.07 max 1 million cells/ml 1.0 403 246 3.9 +/- 0.1 +/- 0.1 0.1 +/- 0.5 +/- 1 +/- 0.25 x 10 6 +/-0.2 +/-0.2 0.2 =/-0.75 +/- 2 +/- 0.5 x 10 6
Laboratory Analyses
What do you need for the analyses?
Minimum Required Laboratory Equipment - General Item <25brl/wk >26brl/wk Temperature probes NOT GLASS THERMOMETERS 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 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 CO 2 meter Y* Y Dissolved CO 2 - * 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 O 2 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 spectrophotometer Haze meter Y Physical Stability Y Beer bitterness & colour, diacetyl, FAN, total polyphenols, wort colour
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? 0 o C - ice 100 o C - 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 CO 2 meters - areas of use? Calibration checks how, when? Corning 965 & 50 μl pipette Sample volume check! Sample chamber care! Total in pack CO 2 Spike care DO 2 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?