I brewed with my cousin for the first time this past Sunday, and he's really anal about sanitation when it comes to his home brews. I totally agree and understand why he's like this. I surely wouldn't want to spend all that time and effort into a batch and have it come out bad b/c a spoon or filter wasn't sanitized properly. Right after we finished filtering the brew into our fermentation bucket and added the yeast, I noticed a drop of sweat (from me) fell into the bucket. Do you think that might ruin the batch? The brew was a fairly basic IPA and he used a recipe he had success with in the past. Didn't want to say anything to him b/c there was nothing we could do about it, so I just kept my mouth shut as they closed up the bucket.
There certainly is some chance that the microbes living on your skin will participate in the fermentation of the beer, but odds are that the anti-microbial properties of the hops, as well as the alcohol and low pH resulting from a strong fermentation by your chosen yeast will prevent the other microbes from producing any noticeable flavor compounds.
I think you will be fine. Years ago I used my mouth to start my siphen from fermenter to my bottling bucket and the beer was fine. ( I was drunk on my second batch! )
I still do that and have never had an infection. Beer is more resilient than many give it credit for.
RDWHAHB I've had sweat, condensation, and tap water drops all fall into my wort after cooling and haven't made an infected batch yet. /me Knocks On Wood
I completely disagree with everything but that the beer will be fine. While hops have antimicrobal properties, this won't stop an infection when bacteria are introduced to wort. Nor will the pH level of beer. The yeast haven't produced alcohol yet and it's going to be a race, just like any other beer, between the yeast added and anything else that was introduced. OP. It's probably fine. May as well sit back and find out.
But the yeast are far more adapted (by evolution) to propagation in the wort environment and are starting with a vastly larger population than anything likely to be in OP's drop of sweat. They have a huge head start in the race.
