Question about really foamy wash

[jackfiasco]

I've been doing pretty much the same washes for several years - Deathwish wheat germ, or a variation - usually use wheat bran or corn cereal because it's cheaper and has nutrients already. Baker's yeast, citric acid to invert the sugar. Boil the sugar and cereals separately for 90 minutes or more each then combine them.

I started 3 washes about 5 weeks ago, each a couple days apart. They were fermenting slow (basement in Seattle winter) so I added aquarium heaters to them and they sped right up. Ran the first batch yesterday no problems. Today I opened the lid on the second one and it had 4 inches of foam on top and a very sharp chemical smell like acetone or something. I get a small amount of foam on top occasionally but never this thick dry foam (looks like a giant rootbeer float) and never this smell.

3rd batch looks fine. All batches started at 1.06. 1st and 3rd batches finished at around .990, but this 2nd foamy off batch is still at around 1.05. What happened?

[Chauncey]

Bacterial infection possibly

[jackfiasco]

That seems the most likely. So is it trash then? Since the gravity is still high I wonder if I could add more yeast and get it working proper or no?

[still_stirrin]

Maybe it was a delayed start? Is the airlock “burping”?

To me, a root beer-like foam head is the sign of high Krausen, or the time when a ferment is switching to the latent phase. A big, “rocky” head is usually indication of proteins/oils in the wort stirred up because of aggressive fermentation activity.

You say it smells solventy, are you sure it’s not vinegar? That would be from a bacterial contamination. But if the smell is “burny” in your sinus, it could be the hydrated CO2 from an active ferment. Does it smell like fingernail polish remover (ethyl acetate)? That’s an ester produced during fermentation that can be further reduced (oxidized) to ethanol.

I’d wait a few days before deciding to “kick the bucket over”.
ss

[Chauncey]

yea id wait but that acetone smell is usually from hot ferments or acetobacteria ime

[Oldvine Zin]

Sounds like an infection to me. And yes it's f-ing cold here in Seattle

OVZ