The Beer Barons of Milwaukee

Homebrewers and Beer Enthusiasts

The Beginners Brewpot

by Richard Grzelak

July 1994

Flawed Beer & Possible Corrections

In this column last month, we had discussed some problems that may occur in your beer as the result of overuse of certain chemicals, and improper boil. This month, we intend to expand upon that topic.

Once again, the most common problem that a homebrewer will encounter is chill haze. Proper protein breaks will generally resolve this problem, although binding agents may help. This is not truly a flaw in the sense that it has a negative impact on taste, but rather interferes with the aesthetics of the beer.

Another problem that frequently occurs is oxidation. This often results in a cardboard taste in the beer, and may exacerbate certain problems by making the beer more harsh, sour, or bitter. It is either caused by too much air in the bottle, or exposure to fluctuating temperatures, the warmer the beer gets, the more likely that some degree of oxidation will occur.

Occasionally, other characteristics may appear in a beer, and depending on the style, these may or may not be flaws. The American Homebrewers Association has identified the following characteristics:

• Acetaldehyde - A green applelike aroma in the beer. This is a by-product of fermentation, and is generally undesirable, however, it sometimes will be wanted in a barleywine.
• Alcoholic - the warming feeling produced by ethanol and some higher alcohols.
• Astringent - a drying, puckering sensation, like that produced by alum or grape skins. This is most common among whole-grain brewers, and generally is caused by long mashes, and over sparging.
• Bitter - the taste associated with hops. Many homebrewers will over hop a beer for a given style.
• Chlorophenolic - The result of the mix between chlorine and certain organic compounds. If this happens, consider switching to distilled water.
• Cooked Vegetable/cabbage-like - Usually the result of long lag times and bacterial infection.
• Diacetyl/buttery - usually caused by fermentation at high temperatures, however, some bacteria may also cause this condition.
• DMS (Dimethyl sulfide) - A sweet corn-like aroma and flavor. Any number of factors may produce this including improper boil, bacteria, and slow wort chilling.
• Fruity/estery - Banana or applelike flavor in a beer. This will occur with certain yeasts and high temperature fermentation.
• Grainy - a cereal-like taste in the beer. Most common among all-grain brewers, it is usually not desired, however, it may be a defining characteristic of some beers.
• Hoppy - The aroma produced by the hops. By definition, it does not include bitterness.
• Light-struck - The skunk-like smell that occurs as the result of exposure to light. This can be avoided by storing the beer in dark bottles, and limiting exposure to light.
• Metallic/Tin-like - coiny flavor in a beer. Limiting direct exposure to metal will eliminate this problem.
• Phenollc - A medicinal, plastic-like flavor in the beer. Caused by wild yeasts or bacterial infection.
• Salty - The flavor associated with table salt. Usually the result of overuse of certain brewing salts, it can also be produced by some sterilizing agents.
• Solvent-like - Similar to alcoholic, however most often described as acetone-like. This will occur as the result of high temperature fermentation.
• Sour/acidic - Vinegar or lemon-like, tart. Generally associated with bacterial infection.
• Sweet - the taste associated with sugar.
• Sulfur-like - Best described as the taste associated with rotten eggs. Can be produced by some yeast strains, but is usually associated with certain brewing salts and sanitizing agents.
• Winey -a complex taste that can best be described as the combination of alcoholic, estery, and acidic components. It is only appropriate in certain Belgian ales.
• Yeasty -the popcorn like flavor often produced by yeast suspension in the beer, or beer that has been allowed to sit on sediment too long.

Based on the above list, the key factors that result in flawed beers are:

1. Improper sanitation
2. Over or under boiling of wort.
3. Mishandling of finished product. and
4. Poor brewing technique.

By exercising greater care in the process, most of these flaws can be avoided.