pumpkin-and-kettleAs I prepared to brew my second Pumpkin beer I caught up on reading the survey answers from my emails… and came across one that startled me…

The kind that makes you spit your drink… that made me realize, maybe I am the worst brewer ever…

Here’s what it said…

“I think you’re wrong about esters being ‘yeast flavors.’ Actually the yeast flavors brewers try to avoid are the flavors that result from dead yeast and the cannibalization of dead yeast as the fermentation continues, thus the secondary fermentation. I think you need to study up on your fermentation and flavor chemistry before you spread more disinformation.”

… well… thanks for taking the survey first of all… I love questioning my brewing knowledge… I long ago decided to always question what I know about brewing… and so I doubled checked and here’s what I found…

On page 35 of the book Yeast by Chris White and Jamil Zainasheff, the definition of esters is as follows…

“Ester – … a volatile compound formed from an organic acid and an alcohol, and it is esters that provide the fruity aromas and flavors that you find in beer…”

Then a few excerpts from the same page state…

“Ester production varies by yeast strain and fermentation conditions…. the process of combining an acid and an alcohol to form an ester takes some time, since the yeast need to create the alcohol first…

… the yeast produce sterols in preparation for budding new cells… this sterol production takes away acetyl-CoA from ester production, which results in lower ester levels in the beer (Bamforth, Beer Flavours: esters)…”

So are esters yeast flavors? I guess you could argue ‘no’, but esters are produced in part by the different alcohols produced during fermentation, by yeast! and the amount of esters produced is also reduced by yeast!…

There are other factors that come into play of ester production like amount of oxygen in the wort, amount of yeast pitched, temperature of fermentation, the types of sugars being fermented, etc…

And if esters are not yeast flavors, then what are they?

… why would John Palmer write on page 90 of How To Brew…

“… during the earlier phases (of fermentation), the yeast produced many different compounds in addition to ethanol and CO2, (e.g. acetaldehyde, esters, amino acids….)…”

… and why would White Labs describe their yeast such as WLP006 Bedford British as:

“Ferments dry and flocculates very well. Produces a distinctive ester profile. Good choice for most English style ales…”

Hmmm… interesting… What do you think, are esters ‘yeast flavors’? (Click Here To Tell Me)

… and yes I am still studying fermentation…

On to the second part of the answer…(the flavors brewers try to avoid are from dead yeast, cannibalization etc.)… yes, we try to avoid them, but they are very rare with today’s quality of yeast…. and that usually happens if you leave your beer sitting for more than a month, or even longer…

Even John Palmer and Jamil Zainasheff talk about not transferring your beer to a secondary… just primary… and of course there are exceptions…

I talked about this in one of my newsletters back in June: Benefits of a Secondary Fermentor

But you know what really makes me the worst brewer… that I don’t believe what I read until I try it… which is why I’m brewing pumpkin beers by both adding pumpkin to the mash and adding it to the boil…

I’ve heard both sides of the argument… both have good arguments, both have bad arguments…

I’ve heard use canned pumpkin… I’ve heard canned is the worst, use real…

I’ve gotten so many critiques on my Pumpkin ale because I added it to the boil… that I am going to get a cloudy beer because of the starch in pumpkin… etc…. and I heard brewers say they’ve never had a cloudy beer by adding pumpkin to the boil or the fermentor…

… and the thing is that there are many variables that make a beer cloudy.. did the brewer use just barley? 2-row, 6-row?… did they do a protein rest? get a good hot break? cold break? use Irish Moss, or finings? did they cold condition the beer? use good flocculent yeast… and on and on…

… and unless they describe the entire process in great detail, I have to question the results and try it for myself… I document everything in my blog… right or wrong… and some brewers see only my mistakes, not a good first impression…

… well they think I’m the worst brewer… period!

But I’m ok with that…

I will continue to try all kinds of things even if they sound weird just to find out for myself what will help me brew better beers… and then report back with the results in my newsletters… also, what I’ve found works best gets documented into a big binder and added to my Better Home Brew Formula training program…

Cheers!


    2 replies to "Are Esters 'Yeast Flavors'?"

    • darkblade II

      I like your thought processesing – listen to all information, assess it’s worth & try it.
      I always used to say, “How far do you know to lean a motorcycle over in corner before it falls over if you’ve never tried it?”
      I am still at the most basic level of home brewing – using cans of extract & adding pre-prepared ingredients but I am already starting to experiment after only 8 brews.
      Are they any good?
      Dunno – I am prepared to drink them.
      Am I going to be putting the local craft / micro brewers out of business any time soon? I doubt it. Ha Ha.
      keep up good work & just enjoy your brewing & beer drinking.
      Cheers

      • Jorge

        I fished tailed the first day I upgraded to a liter bike (Ninja ZX-10R), and have had a healthy fear of the bike since… needless to say, my chicken strips are about 3/4″ wide! oh well… Brewing is very addicting, even when my brews don’t turn out exactly how I want them to I enjoy them…

        As long as you learn from all of your mistakes and use the new knowledge to brew in the future, it will be rewarding!

        Cheers!

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