Off-Flavors- Acetaldehyde

Acetaldehyde

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Alcoholic

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Acetaldehyde

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

- Green apples Yes, at low L/S/P American - Premature - Allow ferment to levels Lagers (from yeast removal from complete - Grassy character is yeast optional) - can taste and - Premature - Good yeast strain smell acetic flocculation (vinegar) / cidery -Oxygen - Aerate wort depletion prepitching

- Bacterial - Practice good spoilage sanitation

- Oxidation - Beer handling to avoid O2 contact

- long lagering will reduce

Troubleshooting Off-flavors- Alcoholic

Describe/Discuss Ever If so, what styles? How is it caused? How can it avoided/ Appropriate? controlled?

- Hot, Spicy Yes Stronger ales and - High amount of - avoid large lagers fermentable sugars amounts of sugars - Vinous aroma - High fermentation - Lower - A warming, temperature fermentation prickling temperature sensation in the mouth and throat - Low mash - Increase mash temperature temperature

- Underpitching - Pitch sufficient yeast quantity

- Low O2 or FAN - Aerate wort prior to piching

- Yeast strain - Healthy Yeast

- Age

Astringent

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Bitterness

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Astringent

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

- Dry, Mouth No N/A - Extraction of - Don’t overcrush puckering, tannins unpleasant (overcrushing, - Keep sparge temp oversparging) low - in mouthfeel and aftertaste - Alkaline mash - Watch mash/runoff or runoff water pH - tannic, tart sensation - excessive - Reduce hop reminiscent of hopping immersion times grape skins - Polyphenols - Practice good from acetobacter sanitation

- Spices - Reduce spice additions

Troubleshooting Off-flavors- Bitterness

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

- will be tasted on Yes IPA’s - High AAU - Use hops with lower the back of the hops alpha acids tongue and the Pales ales roof of the mouth - Lengthy hops - Reduce hop boil times English Bitters times

- fermentation - Higher temperature temperature and quick fermentation decrease bitterness

- filtration reduces bitterness

Buttery

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Cardboard

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Buttery

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

- in Aroma, Flavor Yes Scotch Ales Diacetyl: - Allow ferment to and Mouthfeel Bitters - Premature complete Dry Stouts racking/ fining/ - Diacetyl Czech Pils lagering Oktoberfest - Low: Nutty, - Low - Higher temperature caramel fermentation primary fermentation temperature - High: Butter, Butterscotch - Mutant yeast - Good pure yeast strain - Mouthfeel, a - Lactic acid slickness on the bacteria - Practice good palate (Pediococcus) sanitation

- Long periods of - Quick wort chilling wort cooling

- Underpitching - Adequate yeast of yeast starter amount

-Too long an acid - Shorter acid rest in rest in mash mash

Troubleshooting Off-flavors- Cardboard

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

Oxidation No N/A - Aeration of hot - Quiet transfer of wort beer when siphoning - in Aroma and or transferring Flavor - Aeration of beer during bottling Initial: Cardboard, - excessive age - Serve beer in paper, wet paper, appropriate amount of stale bread time crumbs, pineapple - High storage -Cool (<55F) storage temperatures temps Later: sherry-like, leathery, woodsy - Adding tap -Add only boiled/ water to finished chilled water to beer without boiling after primary fermentation

-excessive head -Proper head space in space in bottle bottle

Cloudiness

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Cooked Corn

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Cloudiness

Describe/Discuss Ever If so, what How is it caused? How can it avoided/ Appropriate? styles? controlled?

- in Appearance Yes Wheat Beers, Chill haze: - Longer mash Lambics, - Insufficent - Cloudy, hazy American Wheat conversion time - Use protein rest

Permanent Haze: - Use clearing agents - excessive or high temperature sparge - Use filtration

- Reduce sparge temps

- Bacterial/ wild - Practice good yeast contamination sanitation

- Poor, wrong, weak - Use well-flocculating or mutated yeast yeast strain strains

- wheat malt

Troubleshooting Off-flavors- Cooked Corn

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

- DMS (dimethyl Yes American Lagers - Poor sanitation - Practice good sulfide) Cream Ales sanitation

- in Aroma and - Covered boil - Open, rolling boil for Flavor an hour or more - not boiling wort - Vegetal for at least an (Sweet cooked hour corn, celery, cabbage, parsnips) - contaminated - Fresh yeast culture yeast - Shellfish or oyster-like in - Over-sparging - Proper sparging higher amount with water below 160 degrees - Precursor S-methyl- - Overnight - Quick wort cooling methionine (SMM) cooling occurs naturally in Pale malt, turns in - Underpitching - high pitching rates DMS with heat, evaporates

Fruitness

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Light Body

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Fruitness

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

- Esters Yes Ales - Alcohols combining with - in Aroma and American Dark acids at higher Flavor Lagers (very light) temperature. (Ethyl acetate, - Banana, apple, Dopplebock (in Isoamyl acetate, citrus, strawberry, dark versions) Ethyl Hexanoate) black currant, grapefruit, Eisbock - Yeast strain - Choose a different raspberry and used yeast pear, etc - Higher - Lower fermentation fermentation temperature temperatures (Ales around 60 F, Lagers around 50 F)

- High-gravity - Lower gravity wort wort

Troubleshooting Off-flavors- Light Body

Describe/Discuss Ever If so, what styles? How is it caused? How can it avoided/ Appropriate? controlled?

- Watery Yes American Light - Lack of dextrins lagers - Weak - Poor quality malt - Use quality malt Lambics - in Flavor and - Large percentage - Keep percentage of Mouthfeel of sugar sugars small

- Low-temperature - High-temperature saccharification saccharification rest rest - Use dextrin, crystal or wheat malt.

Grassy

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Husky-Grainy

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Grassy

Describe/Discuss Ever If so, what styles? How is it caused? How can it avoided/ Appropriate? controlled?

- in Aroma and Yes, as a hop American Pale Ale - Poor quality malt - Good, fresh malt Flavor character English IPA stored under airtight America IPA - Poor storage of conditions - Fresh-cut grass Imperial IPA malt

- New-mown hay - Cracking grains - Cracking grains well in advance of shortly before brewing brewing

- Some English - Choose a different and American hop hop varieties

- Dry Hopping

- Oxidation of alcohols creating hexanal and heptanal

Troubleshooting Off-flavors- Husky-Grainy

Describe/Discuss Ever If so, what How is it caused? How can it avoided/ Appropriate? styles? controlled?

- in Aroma and No-Husky None - Excessive grain - Proper crush Flavor crushing Yes-Grainy Light Lagers - Cereal Pilsners - High Sparge - Lautering - Grainy N. German Alt temperature temperatures - Huskiness Brown Porter between 164-170° - Spent grains Robust Porter Dry Stout - Excessive sparging - Proper sparge Husky Wheat beers amounts - Tannins from grain husks - High pH during - Monitoring pH of sparging (above 6.0) runoff (keep pH Grainy below 6) - starches in barley malt - High mineral - Water appropriate content in water to style

- Boiling grains - Steeping adjunct grains below 170 degrees

- Improper decoction - Temp. controlled or mashing infusion mash

Low Head Retention

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Phenolic

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Low Head Retention

Describe/Discuss Ever If so, what How is it caused? How can it avoided/ Appropriate? styles? controlled?

- Flat Yes Lambics - inadequate - Adequate protein rest protein rest - in Appearance High Alcohol and Mouthfeel Beers - insufficient or - Use hops with high deteriorated hops alpha acids

- Dirty/oily/soapy - Use clean well-rinsed glasses glasses

- low-temperature - High-temperature saccharification saccharification rest rest

-not using a one- - good one hour (open) hour boil rolling boil (to extract the isohumulones)

- Use cara-pils, crystal malt, malto-dextrin, wheat malts

- Lower alcohol by lowering the grist bill

Troubleshooting Off-flavors- Phenolic

Describe/Discuss Ever If so, what How is it caused? How can it avoided/ Appropriate? styles? controlled?

- in Aroma and Yes Some Belgians - Wild yeast - Use pure yeast strains Flavor beers - Improper - Practice good - Band-aid Smoke beers sanitation sanitation - Clove-like - Smoky Some Wheat - Some malt types - Use “clean” malt beer Chlorophenolics - Some yeast strains - Use yeast less prone - Plastic to phenolic production - Medicinal - Chlorophenols in - filter tap water water

- Improper rinse of - Use non- chlorine chlorine sanitizers sanitizers

- Oversparging; - Proper sparging while sparging above pH monitoring temperature 6.0; sparging above and pH 170 degrees

Lightstruck

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Musty

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Lightstruck

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

- in Aroma and No None - Beer stored in - Store beer in Brown Flavor clear or green bottles glass bottles - Skunky - Mercaptan - Beer exposed - Keep beer - Sulfidic (H2S) to direct sunlight or ultraviolet - Ultraviolet light light reacting with isomerized alpha acids

Troubleshooting Off-flavors- Musty

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

Oxidation of malt Yes Bière de Garde - Aeration of hot - Quietly transfer of compounds wort wort/beer when siphoning or - in Aroma and - Aeration of beer transferring Flavor during bottling

- Musty - Cellar-like - Earthy

Sherry-like

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Sourness

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Sherry-like

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

Oxidation Yes Barleywines - Oxidative - Use different yeast yeasts acting on strain - Sherry English Old Ales higher alcohol - Vinous beers creates - Create less alcohol - Leather aldehydes (ie. by lowering grist bill - Woodsy trans-2-nonenal) - Wine-like - Serve beer younger - Paper-like - Old - Ferment cooler

- Accompanied by hazelnut or almond notes

Troubleshooting Off-flavors- Sourness

Describe/Discuss Ever If so, what styles? How is it caused? How can it avoided/ Appropriate? controlled? basic taste Yes Witbier Poor sanitation - Practice good sensation Lambics sanitation Flanders Ale Acid-creating - in Aroma and Berliner Weisse Bacteria’s Flavor (Lactobacillus, (optional Pediococcus, -perceived on sourness) Acetobacter) sides on the American Wheat tongue or Rye, Dry Stout, - Some yeast - Choose a different Witbier and strains yeast - Tart Saison - Sour - Excessive acid - Shorter acid rest - vinegar-like rest aroma - Mashing for less - Mashing too long than two hours - - Scratched plastic - Use glass carboy or fermenter stainless steel fermenters

- Storage at warm - Cool (<55 degree) temperatures storage

Solvent-like

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Sulfury/ Yeasty

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Solvent-like

Describe/Discuss Ever If so, what How is it caused? How can it avoided/ Appropriate? styles? controlled?

- in Aroma and No None - Wild yeast - Good sanitation of Flavor contamination equipment

- Pungent, acrid - High fermentation - Cooler fermentation aroma temperatures temperatures

- Harsh, burning - Lack of oxygen - Proper wort sensation on the oxygenation tongue, back of the throat - Underpitching - Pitch sufficient yeast quantity - Acetone-like - Lacquer-thinner - Non-food grade - only food-grade like plastic equipment plastic used - Turpentine

- Ethyl acetate

Troubleshooting Off-flavors- Sulfury/Yeasty

Describe/Discuss Ever If so, what How is it caused? How can it avoided/ Appropriate? styles? controlled?

- in Aroma and No None - Bacterial - Practice good Flavor contamination sanitation

- Rotten eggs - Wild yeasts - Yeasty - Meaty - Yeast strain - Good yeast strain

Sulfitic- SO2 -- old beer (yeast - Racking off Struck match autolysis) sediment

Sulfidic - Rapid temperature - Cooling lagers no Hydrogen sulfide changes to more than 5 degrees (H2S) fermenting wort per day

Low level: Garlic, onion

High level: burnt rubber, shrimp- like

Sweet

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

xxx

Minnesota Home Brewers Association: Sean P. Hewitt 1/26/06

Troubleshooting Off-flavors- Sweet

Describe/Discuss Ever If so, what styles? How is it caused? How can it avoided/ Appropriate? controlled?

- Basic taste Yes - High levels - Quick - Yeast strain with sensation desirable in most flocculating or Low good attenuation strong ales and attenuating yeast - taste perceived lagers strain primarily at the tip of the tongue - Low levels in - High-temperature - Low-temperature American light mash mash - Due to the lagers and lambics presence of - Addition of - Reduce the grain reducing sugars dextrin malt, malto- dextrin, crystal - Sugary malt - Syrupy - Addition of - Reduce the amount lactose or licorice

- Poor yeast health - Add yeast nutrients, Proper wort oxygenation

- Premature - Lagering, after lagering primary fermentation

Troubleshooting Off-flavors- x

Describe/Discuss Ever If so, what styles? How is it How can it avoided/ Appropriate? caused? controlled?

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