Off flavors in beer

I’m studying for my beer school exam and I’m learning off flavors in beer and how they are caused.

Here are the 11 off flavors and a description of what it tastes/smells like and the possible cause. If you are served a beer with these flavors – return it!

  1. Catty – tom-cat urine, ribes, blackcurrant leaves. Caused by contamination of raw materials.
  2. H2S – Rotten eggs, sulphidic. Caused by yeast during fermentation and during maturation.
  3. Isoamyl Acetate – Banana, fruity, esters (small amounts are acceptable in some beers ie. wheat beers). Caused by yeast during fermentation.
  4. Lightstruck –  Skunky, sunstruck. Caused by exposure to light.
  5. DMS – Creamed corned, cook vegetables, tomato. Caused by malt during wort production and bacteria contamination during fermentation
  6. Sour – Sour milk, lemon, acidic. Caused by raw materials, fermentation, bacterial contamination due to poor hygiene control.
  7. Diacetyl – Butter, butterscotch, milky (small amounts are acceptable in some beers). Caused by yeast during fermentation and contamination of bacteria when hygiene standards are inadequate.
  8. Isovaleric – sweaty, stale cheese, old hops, putrid. Caused by using old/degraded hops.
  9. Metallic – Inky, tin, blood. Caused by beer contact with metal-containing materials (brewing plant, raw materials)
  10. Ethyl  Hexanoate – Apple, aniseed, esters. Caused by yeast during fermentation.
  11. Mercaptan – drain, leek-like, rotten vegetables. Caused by yeast during fermentation.
Advertisements

Leave a comment

Filed under bad beer

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s