Tuesday, March 4, 2014

What do beer infections taste like?

Good question.


This past weekend, I had a friend who was infected and today at a great local craft fusion cafe there may have been some infection in ma biere.

For details on how to (without sounding like a beer snob) tell bars you think their beer is infected check out this CraftBeer mag article.

Me- I like that my De Molen Zus & Zo (aka This & That) Saison had a strikingly acidic background. I liked that my Nøgne Ø 2 Captains Double IPA this weekend was a dry, fruit and pine hopped beer that also happened to finished like carbonated sour tarts.

Beer infections

are caused by wild yeast/bacteria strains entering into a fermenting beer. It is a broad term that can refer to many things and be caused by many things.

[caption id="attachment_2513" align="aligncenter" width="458"]ec69477e beer infection... it's still drinkable though, right?[/caption]

Essentially there are two types of beer infections:

Wild yeast

Brettanomyces pediococcus, lactobacillus, or acetobacter

Tart, acid, sometimes musky, vinegar, cheesy or woody 


Diacetyl- buttered popcorn or butterscotch
Acetaldehyde- green apple
Trans-2 nonenal- oxidation or wet cardboard
Dimethyl sulfide (DMS)- cooked corn or canned asparagus
Methyl mercaptan- skunky
Ethyl acetate- nail polish remover
Isoamyl acetate- bananas

Practice your sensory skills with Randy Mosher's infinitely useful book Tasting Beer.

John Palmer's How to Brew explains beer HOW AND WHY beer infections:

Symptom: It smells like vinegar.

Cause 1: Bacteria In this case, it probably is. Aceto bacteria (vinegar producing) and Lacto bacteria (lactic acid producing) are common contaminates in breweries. Sometimes the infection will produce sweet smells like malt vinegar, other times they will produce cidery smells. It will depend on which bug is living in your wort. Aceto bacteria often produce ropy strands of jelly which can be a good visual indicator, as can excessive cloudiness, after several weeks in the fermentor (although some cloudiness is not unusual, especially in all-grain beers).
Cure: If you don't like the taste, then pour it out. Lactic infections are desired in some beer styles.

Cause 2: Wild Yeast/Bacteria Two other bugs are also common, Brettanomyces and Pediococcus. Brettanomyces is supposed to smell like horse sweat or a horse blanket. Raise your hand if you know what a horse smells like. From sweat, I mean. Anyone? I think Brettanomyces smells like leather, myself. Pediococcus can produce diacetyl and acidic aromas and flavors.

One man's garbage can be another man's gold though. These two cultures and Lacto bacteria are actually essential to the Belgian Lambic beer styles. Under other circumstances and styles, beers that taste like Lambics would be discarded instead of being carefully nurtured and blended over a two year period. Lambic beers have a pronounced tartness with fruity overtones. This type of beer is very refreshing and is excellent with heavy food.
Cure: Be meticulous in your sanitation or investigate Lambic brewing.

Why do (some) beer infections taste good?

[caption id="attachment_2512" align="alignnone" width="960"]AZ__4197 Our beloved Cantillon is, essentially, a beer infection in a bottle[/caption]

As the rise in sour beer love evolves and we pucker up to sour beer education, we are transported back to pre-historic tasting beers. A time when yeast control was a thing of the future and we all beers were wild fermented.

As John Palmer stated above, Belgian Lambics are essentially beer that was left out in the open, infected by the wild things in the air and later sipped by beer geeks of the highest order.
Lambic is the beer style who production is most plagued by myth, misinformation, and archaic procedures

-The Mad Fermentationist

Make sure you understand that American's don't make Lambics!

And keep an open mind to Brett-y-nicey infections- they might be just the kick you were looking for.


1 comment:

  1. If there were to be a slight infection in beer or a moderate infection, what are the hazards of consuming said beer? I realize beer is fermented by yeast bacteria,,, I am a noob and have just started homebrewing.Don't want to make anyone ill.Thanks.