FG: 1.001 - not a hydrometer issue

I recently brewed a cream ale with an OG of 1.055 and fermented with wlp001 California ale that I built up in two starters. This is only the 6th batch I have brewed but the fermentation went a little longer than usual.

I saw airlock activity within the first few hours and within 24hrs there was about 3 inches or krausen. By 60-72hrs it was blowing out pretty violently which I always like to see but it kept going for several days into day 7 even. The yeast didn't even completely fall to the bottom until after day 14.

Last night (day 24) I took a sample with my calibrated hydrometer (distilled water) and the gravity was 1.000-1.001ish. It tasted pretty light in flavor but it is a cream ale after all. (For the record, I even double checked my hydrometer in distilled water again at the correct temp and it was spot on)

Went ahead and put the airlock back in and what do you know, it was still bubbling. Took a little time for the first one to come out but after that maybe 1 bubble every 90seconds..

Is it safe to say I am dealing with a gusher infection here???

Seems hard to believe it would be just simply releasing residual co2 this late in the game and with such a low gravity.

Any input is appreciated!

 

Why would you think you had an infection?
There is nothing left to eat, the bubbling is just CO2 coming out of solution.

Did you use sugar in the brew? This will turn yeast violent and dry out your beer.
Was this an all grain brew? If so mash temp dropped too low (under 150F) for an extended period of time.

Never really heard of a "gusher infection", going to have to look it up. I assume that it is nothing more than a rouge high attenuating yeast like WLP001 or EC1118.
WLP001 has high attenuation, marketed as 80% but can go nearly as high EC1118.
Looks like you had a very healthy starter, they ate quickly but took some time to clean up their plate.

 

Agreed with the above, and will add re: bottle gushers that there's really nothing left to eat here. A gusher / exploding bottle situation would happen when a beer was bottled with residual sugars and during natural carbing in the bottles, more sugar is fermented than planned (be it by residual brewer's yeast or an infection from unintended bacteria). This could happen if you bottled too early / if your brewer's yeast had more sugar to eat in the bottles, or in an infection, if fermentable sugars were consumed but unintended bacteria took hold and munched at residual complex sugars, but I would think if you're down to 1.001 either way, there's nothing left to consume outside of the sugars you would add at bottling for your desired carb level.


But I agree that there's no reason to suspect an infection here vs. a highly-fermentable wort + good attenuation from healthy yeast with a (probable) high pitch rate (two starters for 1.055)

 

It was an all grain brew and yes, I used sugar. Mashed at 149F. I guess the thought of the gravity matching that of distilled water has me concerned. Is it normal to have that low of a gravity?? I was expecting 1.005 at the lowest.

From what I have read, a gusher infection typically comes from a wild yeast strain that consumes the larger/more complex dextrin's a typical brewers yeast leaves behind. I have had one before and when you crack a bottle, it gushes out. They get worse over time as the wild yeast strain keeps consuming and further carbonating until the beer is rendered flavorless (or until the bottle explodes).

 

Correct. Though at 1.000-1.001, you don't have much sugar left to eat, complex or otherwise. I only have a vague familiarity to cream ales and general recipe guidelines (and am not familiar with WLP001's characteristics) but if you used all base malt + corn sugar + mashed low (and depending on what equipment you have, you may lose some temp over the course of a mash and only get lower), you could ferment nearly water-dry. All depends on the variables at play.

 

Thanks for the input guys. I suppose I'll bottle it and pawn it off on the friends and relatives with a weak pallet

 

It is not normal to have that low of a gravity in a beer, but what you made is not normal.
You created a very fermentable wort with very little complex sugar; like a wine.
So it is no surprise that it finished near 1.0

FYI
Wild yeasts are not high attenuating; they are also not very alcohol tolerant.
There are some bacteria strains that can produce enzymes that can continue to break down complex sugars.
You don't have either, WLP001 out competed everything else on the first day.

 

Certain yeasts (saison yeasts in particular) routinely go that low. I ended around 1.003. Hope it tastes good! Dry beers are a favorite of mine! Feel free to send some my way if you're overly worried

 

I guess I'm odd man out, but it seems to me there's very likely an infection in that beer. Probably a good tasting infection since you didn't mention a bad flavor. I hope you'll post how it tastes after conditioning - normal or funky.

 

I would say it is probably due to the highly fermentable wort, combined with the possibility of infection. I doubt any infection could take it much lower so bottle bombs or gushers should not be an issue. If it tastes good, proceed.

The bubbling you see is most likely co2 coming out of solution. I have a beer that has been sitting in a carboy for 2 months where I can hear it, It bubbles every now and then. Air pressure or temperature changes....

 

Bottled yesterday and tasted a sample as I always do before bottling. Tasted fine, no funkiness or identifiable off flavors. I'll update in a couple weeks. Cheers!

 

I think you just over pitched if I had to guess. You said you built it up in 2 starters. Not sure how big of a starter you pitched. A 1L starter for 5 gallons at 1.055 would suffice. It's a pretty aggressive yeast too.

The infection gushers I've had have always been down the road. It usually taste great then slowly declines, with a bit of a metallic taste.

 

Update. Just cracked one open and it's not great... there is a ton of green apple (Acetaldehyde) and a slight buttery aroma (diacetyl) on the nose and it becomes more apparent in the flavor as it warms up. I would think this is due to infection as my pitch rate was more than sufficient and fermentation temp was pretty spot on throughout the 4 weeks it was in the primary fermenter. Although this is disappointing, I'll take it as a learning experience.

I am thinking the infection came from my blow off set up. It is a piece of tubing connected to a 3pc. airlock and it was the third time I used it.

Has anyone else had problems with this type of blow off set up?

I find they are hard to clean since once the tubing is on, it can't really come apart.

 

I clean my blow off tube, stopper and the growler is feed into after every use. I use hot water with a little pbw in my kettle to soak for about an hour, then rinse, and then dunk in starsan just before I put it on.

 

Yea, I do the same but I find it hard to get at where the tubing meets the end of the airlock. I always move it around and get all the gunk out of there but it's what I can't see that I am worried about.

 

I ferment 5 gallons in a 7.9 gallon bucket and don't use a blow-off because I share your concerns about cleaning the blow-off apparatus.

 

I recently got a three gallon batch of ruined braggot in a similar fashion. It really irritates me to expend wasted time and effort due to someone else's carelessness.

While taking a hydrometer reading during bottling, I found my wort gravity to be < 1.005. That's below the threshold for good beer wort, but I bottled with Carbo drops anyway even though the unfinished braggot tasted like fizzy vinegar. Long story short, I now have 12 bombers worth of carbonated malt vinegar and I know why.

This happens when someone irresponsible in your house drops something on the fermenter's airlock and breaks it, then doesn't have the common sense to clean it up properly or tell you until hours later. If the specific gravity of beer wort is below your calculated value and tastes like vinegar at bottling, it probably won't be good beer.