Has anyone had EA develop during fermentation? Not the superficial EA that forms on the top of the cap sometimes, but I am getting it in the wine pulled from the center of the tank.
have read that native yeasts sometimes produce a lot of EA during fermentation but these grapes were innoculated with EC1118 and the fermentation has been flawless, no reduction, temperatures in the high sixties to lower seventies and should be done in the next day or so ( about 11 days total).
Should I warm the tank to 80 degrees to try to blow it off?
I have never had this happen before. What is strange is that I don’t smell it, but I taste it in the wine. I have a fermentation tank and a 1/2 ton macro bin and they both exhibit the same EA in the wine. Something that came in on the grapes maybe?
have read that native yeasts sometimes produce a lot of EA during fermentation
That’s a myth. All yeasts produce EA. They also consume it again immediately, unless stressed for some reason. The most likely cause would be a nutrient deficiency. This is a good reason to have your juice tested after crush. Also, for careful attention during punch downs. Mid-fermentation all you usually need is a little nutrient boost and the yeast will happily gobble up the EA. But, since they’re your mechanism for correction, near the end or post-ferment there’s not a lot you can do. (And nutrients that late would be fodder for bad beasties.)
Thanks Wes. I read that EC1118 will produce acetic acid under stress. So I decided to do a rack and return on the tank with splashing to see if adding more oxygen during pump over does the trick, plus EA is volatile so that may blow it off. Nutrition level is fine, so if it caused by yeast stress, it is for some other reason. I will report back tomorrow and let you know if that worked
I believe you’re mistaken about yeast (S. cerevisiae) consuming EA…in fact, EA and VA are toxic to yeast. Are you thinking of acetaldehyde, which is an intermediate product in proucing alcohol?
Some native (S. cerevisiae) yeast do produce a lot of EA early on in a fermentation. Kloeckera is esp this way (it dies at 6% alc tho). The best solution is to get the fermentation temps above 80…which will blow off all the EA, for all intents and purposes. Once fermentation is complete, it’s quite difficult to get rid of the EA unfortunately.
I’m pretty sure I’ve read about the phenomenon Wes mentions – yeast consuming EA during their growth phase. I can’t find a cite in my go-to reference, The Handbook of Enology, but I think it’s there somewhere. The index isn’t great for quick keyword searches.