Troubleshooting

2008-04-30T15:17:24Z

Jkendo:

Here is a list of common off flavors and aromas and potential causes for '''troubleshooting'''.

'''Alcoholic:''' A warm prickly sensation in the mouth and throat.
*Increase Fermentable sugars through use of malt or Adjuncts.
*Healthy and Attenuattive yeast strains
*Within the general 145-158 degree F range of mashing temperatures the lower mash temperature produce more fermentables, thus more resulting alcohol.
*Aeration of wort before pitching aids yeast activity.
*Fusel (solvent-like) alcohols are procuded at high temperatures
*Age and oxidation will convert some of the ethanol to higher solvent like alcohol.

'''Bitter:''' A sensation generally percieved on the back of the tongue, and sometimes roof of the mouth, as with caffeine or hop resin.
*High: Black and roasted malts and grains
*High: Great amounts of boiling hops
*High: Alkaline water can draw out bitter components from grains
*High: Effective boiling of hops
*Low: High fermentation temperatures and quick fermentation rates will decrease hop bitterness
*Filtration can remove some bitterness.

'''Body:''' Not a flavor but a sensation of viscosity in the mouth as with thick (full body) and thin (light body)beers.
*Full: Use of Malto-dextrin, dextrinous malts, lactose, crystal malt, caramel malt, dextrin (CaraPils) Malt
*Thin: Use of highly fermentable malt
*Thin: Use of enzymes that break down carbohydrates in mash, fermentation or storage.
*Full: High Temperature Mash
*Low: Low Temperature mash
*Low: Age will reduce body
*Low: Wild Yeast and bacteria may reduce body by breaking down carbohydrates

'''Diacetyl:''' Butter or butterscotch flavor.
*High Levels: Unhealthy, non-flocculating yeast
*High Levels: Not enough soluble nitrogen-based yeast nutrient in wort.
*High Levels: Not enough oxygen in wort when pitching yeast
*High Levels: Bacterial contamination
*High/Low: Yeast strain will influence production of diacetyl
*High Levels: Excessive use of adjuncts such as corn or rice, deficient in amino acid (soluble nitrogen-based nutrients)
*High Levels: Chilling fermentation too soon
*High Levels: High-temperature initial fermentation
*High Levels: Premature fining takes yeast out of suspension too soon
*Low Levels: Agitated extended fermentation.
*Low Levels: High temperature during extended fermentation.
*Low Levels: Kraeusening
*High levels: Bacteria from equipment.
*High/Low: Configuration and size of fermenting vessel will influence production.

'''DMS (dimethylsulfide):''' Cooked cabbage or sweet cornlike aroma.
*High Levels: High-moisture malt, especially six row varieties
*High Levels: bacterial contamination of wort.
*Low Levels: Use of two row English malt
*High Levels: Under pitching of yeast.
*High Levels: Bacterially infected yeast slurry.
*Low Levels: Longer boil will diminish DMS
*High Levels: Oversparging at low temperatures (especially lower than 160 degrees
*High Levels: Bacteria from equipment.
*High Levels: Introduction of unfiltered co2 produced by fermentation. Bottle priming will produce small amounts.
*High Levels: Covered pot during boil.

'''Husky/Grainy (astringent)''' : Raw grainlike flavor, dry, puckerlike sensation as in grape skins.
*Alkaline or high sulfate water.
*Stems and skins of fruit.
*Six row more than two row malt
*Oversparging grains
*Boiling grains
*Excess trub
*Poor hot brew (improper boiling)
* Over milling/grinding
*High temperature sparge water (over 175 degrees)

'''Phenolic:''' Medicinal, band-aidlike, smokey, clovelike, plasticlike.
*High: Chlorinated (tap) water.
*Wheat malt (clovelike) or roasted barley/malts (smoky)
*Oversparging of mash
*Boiling grains
*Cleaning compound residue
*Plastic hoses and gaskets
*Bacterial and wild yeast contamination.
*Defective bottle cap linings.

'''Sour/Acidic:''' Sensation generaly perceived on the sides of the tongue sort of like with lemonjuice or sour candy.
*Introduction of lactobacillus, acetobacter and other acid forming bacteria.
*Too much refined sugar.
*Addition of citric acid.
*Excessive ascorbic acid. (Vitamin C)
*Mashing too long promotes bacterial growth and acid byproducts in mash.
*Bacteria in wort, fermentation.
*Excessive fermentation temperatures promotes bacterial growth.
*Bacteria harbored in scratched surfaces of plastic, glass, stainless, improper welds, valves, spigots, gaskets, discolored plastic.
*Use of wooden spoon in cooled wort or fermentation.
*Storage at warm temperatures.
*Unsanitary bottles or keg.

==See Also==
* [[Technical]]
* [[Processes]]

[[Category:Technical]]
[[Category:Processes]]
[[Category:Glossary]]

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Troubleshooting