Troubleshooting Higher Esters and Hot Alcohol in a Kolsch

[cdburg]

I'm hoping to get some input from others to help me figure out a recent issue with my beers. I got feedback from the first round of the AHA comp about a Kolsch that pointed out some flavor flaws I hadn't noticed myself - a slight hot alcohol-like flavor in the aftertaste and higher than expected yeast esters.

I've brewed variations of this recipe for years, and the beer has done decently well in the AHA comp previously. I'm at a bit of a loss what could be causing the issues, especially the slight hot alcohol flavor.

• I fermented at 60 F (Ranco controlling upright freezer with the probe in a thermowell in the Better Bottle).
• I oxygenated, per usual, with 1 liter per minute of O2 for 60 seconds.
• I bought the yeast locally (no shipping damage) and pitched the amount recommended by the Mr. Malty calculator.
• I used the recommended dose of Wyeast yeast nutrient.
• The beer went from the Better Bottle to a keg, pushed with CO2.
• The beer aged for almost two months before the competition.

I'm going to check the temp on the Ranco unit to make sure it's accurate. I haven't done that in a while. I'm pretty sure it's within a degree or two though. The oxygen amount is the same as what is recommended in "Yeast: The Practical Guide to Beer Fermentation."

Does anyone have any ideas what could be causing the higher than desired esters and the slight hot alcohol-like flavor?

[BDawg]

Everything looks ok to me. JZ mentioned over-oxygenation as a potential cause of harsh/hot alcohol, but 60 seconds seems perfectly fine to me.

Get another set of taste buds to comment on it. It might be that the judges were simply finding things where they don't exist, or maybe it's a handling thing or even something else (For example - sanitation? -- Leave a couple bottles warm for a month and then taste them see if they develop any off flavors. You never know, maybe the warm transport let some bugs take hold that would not ordinarily have a chance to grow. My point is test everything so you can rule it out.

Feel free to pm me for my address and I'll evaluate it for you if you can't find an experienced palate near to you.

That goes to anyone - I'm more than happy to evaluate any beers for anyone if they want me to.

[cdburg]

Normally, I'd agree with you about it possibly being the taster, but the judge for this beer was Nicole Erny. If it was almost anyone else, I would have taken it with a grain of sale. In this case though, I really do think she has a far better palate than I likely ever will. After reading the comments and re-tasting the beer, I also agree with she said. I just never would have noticed it on my own.

The beer scored ok (35.5) but that is a step down from the scores in previous years. I thought about over-oxygenation at first too, but it seems unlikely. I'm pretty careful about cleaning and sanitation, but it could definitely be something to take a closer look at, just to try to eliminate it entirely.

I think I may need to find another tester locally for some more feedback and ideas. If I can't get it figured out, I'll definitely take you up on your offer. Thank you!

[BDawg]

Yeah, no question Nicole has a great palate. You can trust if she said something is there, it's there.

One other thing to think about - How much sulfate was in your water? It could potentially elevate your hops to the point of harsh which she was interpreting as alcohol harshness. I've noticed that gypsum and noble hops don't mix as well as gypsum and American or English hops do.

The link below is very useful if you are looking for experienced people to taste your beers. It is a list of all the National and above BJCP judges sorted by state/city. (We use this list to help exam administrators locate qualified exam proctors). Look for the cities close by you and if you click on the judge's name it will pop up your email program so you can email them directly:

http://www.bjcp.org/apps/reports/proctors.php

HTH-

[cdburg]

Sulfates should be fine. I used the "Yellow Balanced" water profile from Bru'n Water with a 50/50 split of gypsum and calcium chloride. I also used a carbon block filter and campden (to be sure) for the water to get rid of any chlorine, so I'm pretty sure that couldn't be a source of anything.

Thanks for the link! A good resource for finding experienced palates around here would be very useful.

[spiderwrangler]

Di dyou drest you're kolsch?

[cdburg]

Heh. Awesome...

Di dyou drest you're kolsch?

[EagleDude]

couple of thoughts ... how were your numbers? ... did you hit your starting gravity or end up a bit high? Also, did you change yeast distributors? Wyeast vs. white labs the two kolsch strains give very different levels of esters. Do you remember where the moon cycle was during NHC judging? .... next time Nicole is on the session definately ask her if the moon cycle effects perception.

I am curious to here what you find out ... sounds like you pretty much do everything right.