Sensory Evaluation in the Brewery Evaluate Flavour & Aroma Profiles Analyse Solve Problems Presented to the Kwantlen Polytechnic University By Jim Holden Water, CO2, Air, O2, Ingredients (yeast, malts, adjuncts, hops, and mystery flavours ), Filter Aides, Wort, Beer, and at the Consumers. Taste and Aroma on all

Outline of Lecture Why we taste? Introduction The Setting (Sensory Evaluation Room) The Panelists The Pour Description of Types of Taste Groups The Sensory Wheel Paper Work Statistics Brewing and Packaging Effects on Taste Why a Good Beer? Why A Great Beer? Lab Analyses & Tasting Regimen Quickly..The outline is a good guide of entire Sensory course including ingredients (Water, Hops, Malt, Adjuncts, D.E., Co2, O2, Air, N2,

Why Taste? Consistency Trial Changes to Product Compare Our Own Brands Compare the Competitors Brands Correct Defects Ask students to comment

Where -The Setting Very Clean and Odor Free (No Smokers) Neutral Colours, Well Lighted Partitioned Booths for Panelists Room Temperature A Sensory Profile Reference Available

The Beer Tasting Wheel

Who - The Panelists Panelists Have Strengths & Weaknesses Trained In Various Flavours & Aromas Have Thresholds Assessed Able to Detect Low Levels Tested Annually for Ability Non-Smokers Engaged In Their Work Most panelists are able to detect aromas and tastes within a predetermined specification e.g. Diacetyl <.15 ppm but they cannot detect all components e.g. chlorophenol. Smokers are particularly offensive to the panel as they tend to have tobacco aromas embedded in their clothing/hair. The lab can make up a series of solutions with a range of concentrations that can be used to screen potential panel members.

The Pour (Blind Samples) Glass’s Should Be Extremely Clean & Odorless Red or Opaque With Uniform Size Samples Poured With Same Head Samples Should Have Same Temperatures (100C) Panelist Should Not Be Rushed Provide Mouth Rinse (Unsalted Soda Crackers/Water) Traditional 11:00 AM Taste Time. Blind samples to exclude identification. Unless colour is to be evaluated. Sample must be warm enough to release aromas. Don’t taste in late afternoon

Types of Taste Tests Monadic – The Taster Comments On a Single Sample. Perhaps to Rate Acceptance Only Paired Comparison – for Characteristics or Trial Comparisons, Preference. Triangular – Two Samples Same, One Different. Find the Odd Sample or Preference. Duo-Trio – Panelist Knows the Two Different Samples But Must Match the Third Unknown to One of the First Pair. Monadic: Acceptance. Paired Comparison: Trial Comparisons, Preference. Triangular: Find the Odd Sample out of Three. The Duo-Trio is less tiring to the taster.

Taste Panel Types Monadic Paired Comparison Triangular Duo-Trio

Results – Keeping Track First column for Taste. Second for Aroma. Rate 1 to 5 First Rows for Hop Characteristics Hop Characteristics, Body Balance Acceptance, Scale of 1 to 5 (week to strong)…Sensory taste researchers argue over the Scale as well as the categories. Bottom Rows for Body, Balance, and Acceptance. Important for Statistics. 3.5 4.0 4.0 4.0 e.g. X =3.75

Statistics The Distribution Chart Probability Standard Deviation Null Hypothesis Testing Range, Means etc Multivariant Analyses (ANOVA, Chi Square) Significance The Distribution Chart, One and Two Tailed Tests, Probability, Variance, Deviation from Mean, Significance….Possibly Multivarient Analysis (ANOVA, Chi,). Easiest method is to add up preference results for each taster and determine the Mean. Null Hypothesis..Beer 1 is same as Beer 2

The Adventure Water Filter Aides Cereal Cooker Kettle Lauter Tun Chlorophenol Phenolic Acidic Bacterial Mouldy Gushing Estery Sweet Grassy, Husk Earthy Metallic Gushing Body Caramelization Water Mill Malt Adjunct Hops Filter Aides Cereal Cooker Bitter Bite Rubbery Obesum. P. Pediococci Parsnip Body Enzyme Poisons MouthFeel Cooked Resinous DMS Hop Body Grassy Husk L. Diastaticus Kettle Lauter Tun Mash Tun Adjusting Water pH for enzyme action and taste. Fusarium contamination of Malt. High Micro Count in Corn Syrup (AW-Water Activity). BSI= Beer Soluble Iron. <3.00 ppm. Fe in beer <.10ppm (Gushing, Metallic flavours). Overly tight Mill settings > to much husk finnings and flavour. Lacticobacillus and Pediococcus (Gram Positive, Catalase Negative) >Diacetyl, Turbidity, Ropiness. Enzyme Poisons > the craft brewer must not become a chef with disregard for mashing enzymes > Proteases break down insoluable proteins into soluable(peptones and polypeptides) that affect mouthfeel then further to peptides and amino acids and NH4 for assimilation by the brewers yeast. All of these enzymatic reactions are dependent on optimum temperature and pH control. Diacetyl/VDK Sulphitic Autolysed Yeasty Estery Acidic Papery Oxidized CO2 O2 Air Filter BSI Hot Wort Tank Grainy Ferm. BBT HE Tert. Amyl Alcohol

Fermentation Excellence Cells VDK oP pH SO2 SO2 – 85 ppm Problems with fermentation is most likely the greatest contributor to beer off-flavours. SO2 is produced by yeast in very high concentrations but will reduce to 3-8 ppm by the end of fermentation. ….Banana esters (e.g., isoamyl acetate) Apple esters (e.g., ethyl hexanoate) Fusel alcohols (e.g., isoamyl alcohol), C6, C8, C10 aliphatic acids, Ethyl acetate, Butyric and isovaleric acids, Phenylacetic acidrs. Mashing Flavours Bitterness, Astringency pH Sweet, Worty, Body A.E. Cells x 106 Yeasty, Sulphite, Autolysed, Diacetyl Diacetyl Dairy, Acetylaldehyde

The Finished Product Saboteur The Packaging Line and Consumer Flat Short Fills Erratic Fobbing Transfer from BBT Bottle Washer/ Pasteurizer/ Can Rinser Beer Filler Membrane Filter Caustic Carryover Foreign Matter Glass Inclusion Enamel Inclusion Dissolved Oxygen Papery, Acidic CO2 Burnt Heat Caramelized Can/Bottle/Keg Filling can have a profound effect on the outcome of Beer Flavour. Everything from BBT and Filler Counter Pressure, to BBT Micromat, to method of fobbing and shaky conveyors. Keg beer can be spoiled with Acetic Acid Bacteria if O2 is allowed into the keg (Dirty Kegs, Tavern Lines, CO2 . Lactobacillus Diastaticus utilizes Dextrins rather than carbos to produce Diacetyl but does not produce CO2 or Ethanol. Skunky: Degradation of Thiol Amino Acids and catalysed by Riboflavin (B1) in light below 530 nm > methyl butene thiol MBT. Consumer/Tavern Acetic Acid Skunky Papery, Cardboard Oxidized Bite. Warm, Skunky Dirty Lines Old Product

Good Beer Vs the Great One A Great Recipe Quality Raw Materials Customer Acceptance/Readily Distinctive and Unique Quality Assurance (Rigorous Analytical and Sensory Testing). Tight Specifications. Excellent Sales & Marketing (Label, Bottle, Carton and sales) Enduring Miller High Life, Budweiser, Granville Island Pale Ale. Consistency, Recipe, Quality Assurance, Enduring, (eg. Budweiser Est 1876, Miller Brand 1903), and a Great Marketing Plan….don’t forget the label…flint bottles etc. Miller Highlife and Budweiser are two of the most popular beers in the world. One uses Corn Syrup the other Rice for adjuncts. Budweiser has a much different yeast than Miller (slow flocculation > beechwood chips to increase Krausen fermentation yeast surface area. The similarity of the products are in that both Miller and AB have wonderful control of the brewing process. e Miller Brewing Company use modified hop extracts called tetra-hop instead of using hop flowers to bitter their beers. These contain isomerised alpha-acids (amino acids) with a modified molecular structure, and are unaffected by exposure to light. The extract is reported to have added benefits by greatly increasing the foam retention of a beer, however it also alters the flavour of beer….. Each area of their process has “Repeatable Results”.