Infection?

[Kyle]

I brewed a raspberry pale ale with 3 pounds of pureed raspberries from a can. I checked the secondary fermenter today and noticed a white scum. Is that is brett or some unknown bacterial infection?

If so, is it still safe to drink? it smells good.

The picture below makes it look less significant than it is: there is a very noticable white film on the surface of the brew, and there are creases in the film. It is the creases that are clearly visible in the photo.

[Dave Savoie]

Ive had the white stuff before not good

[Dave Savoie]

Siphon below the white film leave beer in carboy so you dont suck up the white

[Kyle]

yeah, will keg and chill tomorrow if its still ok.

[Shawn]

I don't have a lot of experience with infection (at least not that I know of), but that doesn't look good. I know the Flanders Red I stil have in primary has a white film/pellicle on top, which is normal for a beer like that (that has Brett, as well as several other souring bugs).

You don't have to worry about it making you sick. Beer infections may taste bad, but they won't harm you at all.

[Kyle]

Yeah, I've been researching the likelihood it would make me sick, and it does seem unlikely, so I'll be kegging it shortly, with care. I've been brewing so long with no infection that I've gradually slid a bit from my religious cleaning schedule. I soaked the autosyphon in star san but I didn't scrub it, quite possibly the source of the problem. Or the raspberry puree was an issue.

So maybe I have an accidental lambic. (edit: joking see below!)

[Dave Savoie]

Raspberry should be able to stand a bit of sourness
and still be very good may be one of those very good beers you can never reproduce think positive and stay thirsty !!!

[Shawn]

A lambic beer will take anywhere from 1-3+ years to be ready... I'm not trying to be pessimistic here, but just because a beer becomes infected doesn't make it another style of beer. The only reason I mention this is because the Wyeast I used for the above-mentioned Flanders Red is the Roselare blend, which has a typical Saccharomyces strain, 2 Brett strains, a Pediococcus, and a Lactobacillus... I pitched it 6 months ago, and it STILL doesn't really taste that sour. Definitely has some of that barnyard funk that you come to expect (and love) with Brett, but...

Either way, at least it won't make you sick, and it really does happen to everybody at some point.

And now you've got me craving some Cantillon...

[Kyle]

ah, yes, the idea of it being a lambic was not intended to be taken seriously. It's been a bit of a running joke here that infection = accidental lambic after someone attempted to make a lambic last year with open, outdoor fermentation and no specific yeast or symbiots added.

Actually, I tasted the raspberry PA and its quite good. It is carbing up now. I am wondering if the white film could be Starsan residue, since it looked exactly the same coming out of the carboy when rinsing with plain water, as the white stuff that floats to the top during a regular Starsan bath, just to be on the safe side, I'll make the keg go quickly.

[Dean]

there's been a few infections lately ...both confirmed and suspected, I'm wondering if there's a common denominator that we're missing. High ambient temps and humidity maybe? Perhaps we should be taking this into consideration and be a little extra diligent with our sanitizing regimes.

I don't know if my "orange wit" is infected but I sure don't like the up-front taste, and I know for certain that it was during a hot/muggy period when it was bottled .....just a thought

[Kyle]

The very warm temperatures do lead to unpleasant flavours and aromas, but the recent series of infections is probably due to people (me included) getting too lax with properly scrubbing before sanitizing.

[Shawn]

Actually, I tasted the raspberry PA and its quite good. It is carbing up now. I am wondering if the white film could be Starsan residue, since it looked exactly the same coming out of the carboy when rinsing with plain water, as the white stuff that floats to the top during a regular Starsan bath, just to be on the safe side, I'll make the keg go quickly.

I don't THINK it would be Starsan residue... the foam that accumulates when sanitizing usually disappears pretty quickly and is never seen again. Maybe it did get slightly infected, but you haven't been able to tell in the taste yet, like you mentioned... in which case, yes, drinking it fast is the best route.

[Dean]

The very warm temperatures do lead to unpleasant flavours and aromas, but the recent series of infections is probably due to people (me included) getting too lax with properly scrubbing before sanitizing.

yeah that's what I'm saying ...since bugs grow better when it's hot and humid maybe we should be using a little more elbow grease than when the weather is more favourable

[Richard]

I don't THINK it would be Starsan residue... the foam that accumulates when sanitizing usually disappears pretty quickly and is never seen again. Maybe it did get slightly infected, but you haven't been able to tell in the taste yet, like you mentioned... in which case, yes, drinking it fast is the best route.

+1... that ain't star-san. At best it's some by-product of the puree, or some form of starch collecting.

Your picture looks identical to that of this thread:
http://www.jimsbeerkit.co.uk/forum/view ... =7&t=36609
Say hello to the mother of vinegar:
http://en.wikipedia.org/wiki/Mother_of_vinegar

Which ultimately means it's likely acetobacter is the cause. The aerobic nature of the contaminant means it sits at the top of the beer and does not spoil the beer as quickly as lacto/pedio/brett would - hence your beer tasting fine atm. I'd drink it fast - but at worst you'll end up with some raspberry vinegar

I suspect if you keg it, the pressure + lack of O2 will suppress further growth.

[Shawn]

Which ultimately means it's likely acetobacter is the cause. The aerobic nature of the contaminant means it sits at the top of the beer and does not spoil the beer as quickly as lacto/pedio/brett would - hence your beer tasting fine atm.

That sounds like good reasoning... if it were Brett, from what I understand, the white film that forms is more encompassing and complete... like a white sheet covering the whole surface of the beer. Not to mention that it can take months to form, as I mentioned before.

So... keep on drinking...