On several consecutive batches now I've had varying degrees of this soapy, slightly chemical like off flavor. I've had some trouble figuring out what might be causing it. I don't use actual soap or bleach or anything at any stage in my cleaning process: I use oxyclean for cleaning and starsan for sanitizing. I also don't think the off flavors could be coming from autolysis which is the textbook cause, as I typically only have beers in the fermenter for around three weeks, and all have been bottled within a month of when yeast was pitched. I only have a few ideas of what the problem could be: 1) Some kind of off flavor from high fermentation temperature. I've used US-05 on all of these batches (all IPAs or other hoppy styles). I think the ambient temperature in my basement, where all my fermenters are, is probably around 68. I haven't noticed the temperature strips on any of my buckets reading above like 70-71 but it's possible they got higher as I don't check the temps very often. Anyway this seems unlikely as even low 70s is within theoretically acceptable range for US-05, and I haven't heard of soapiness as an off flavor from higher temperatures anyway. 2) A problem with chlorine/chlorophenols. I've used tap water for all these batches and haven't been using campden tablets or anything. This seems like the most likely explanation, BUT the off flavors I get are more soapy than medicinal/rubber bandy, and also the taste samples I've taken when doing gravity readings after primary or at bottling time don't seem to have the soapy off flavor. And my tap water doesn't taste particularly soapy or chlorine like... 3) Something in the bottles themselves at bottling time. Again, I use oxyclean and starsan to clean bottles, but given what I mentioned above about samples at bottling time tasting okay and then bottles later having a soapy flavor, I wonder if this isn't it. I took extra precautions last time I bottled to clean all the oxyclean solution out of bottles before sanitizing and to make sure the sanitizer water was totally clean aside from sanitizer, so I'll see how that batch of bottles comes out. I'm going to start being more careful with bottles as I said, and also just got some campden tablets to start using on strike and sparge water, so that will eliminate a few variables and hopefully eliminate the problem. But I'd really like to be able to figure out exactly what's causing this, and wondered if anyone here has experiences that might shed some light. Sorry for the long post, thanks in advance for any replies.
No--I mean they're all hoppy beers of one kind or another but different hops in each, not even the same base malt as I switched from Briess to Rahr recently. I rehydrated yeast on most batches but not all, put whirlfloc in some but not all, I did put gypsum in all batches I think. There also seems to be a bit of variation between bottles in how much soapy flavor there is, but maybe that's my imagination. The off flavor is usually subtle enough that the beers are plenty good anyway but they'd be great without it and its really frustrating to have that subtle weirdness time after time.
Did you taste the beer before/at bottling time? Was the off flavor present? I had an issue a while back that sounds familiar to what you describe. I first blamed a poor rinse of oxyclean, so I bought pbw. When it happened again I scoured BA and HBT forums and thought maybe it was the water so I switched to all spring water for the beer and added campden to my rinsing water. After the 3rd ruined batch I discovered that my 3-piece spigot had some nastiness in the crevices that could only be reached by tearing it apart with pliers. My spigots now live in starsan-filled tupperware when not in use.
The spigot is the little faucet that you screw in. Was the off-flavor present in the bottling bucket?
I didn't notice the off flavor in bottling bucket but that doesn't mean it wasn't there and just below taste threshold until cold and carbonated. Also, at least one batch that I bottled straight from carboy with a siphon and no bottling bucket also had this flavor, so it can't just be a bottling equipment thing (I also use two different siphons and numerous different fermenters).
Another possibility that spans all the batches but hasn't been raised yet, glassware... everything tastes great until post bottling, then bam, and it can be hit or miss. How do you wash your glassware that you drink from? Dishwasher? If so, what kind of soap do you use, could your rinse cycle be trippin sometimes making the soap not come off all the way? Hand washing? What kind of soap do you use? Hot or cold rinse? How well do you rinse them? Does your significant other do the dishes sometimes (might not be as meticulous as you in proper washing and rinsing of beer glasses)? I have a low threshold for soaps and cleaners at times, I can pick up bleach in a restaurant tasting glass where they swear they don't use bleach in there washing cycles (could be a part of the soap mix).
Try using Campden tablets Chlorine can cause all sorts of nasty flavors in your beer. It's really cheap I got a whole bottle of them for $1.78 at my LHBS and have not had a bad tasting batch since.
Some varieties of hops can be rather perfumy and have a soapy taste as well a some commercial beers for whatever reason...Loft from New Belgium comes to mind...perhaps it is the Kaffir???
I'm surprised nobody mentioned this... soapy flavors can be the result of fatty acids in the trub breaking down. Do you get a lot of trub in your fermenter and/or leave the beer in the fermenter for an extended period?
Nope, as I mentioned I only have beers on the fermenter for 3-4 weeks. Lots of hops so lots of trub from dry hops but they're only in there 9-10 days usually.
