What is the dormancy temperature for acetobacter?

[Pivzavod]

One of my last batches (Lemongrass Wheat) had a little bit of acetobacter infection when I moved one of my primaries for bottling & loosened up the lid. It was only for 2 days and then I racked it to a keg, purged with co2 and put in the kegerator and kept pressurized. Today I tasted it and there is a pronounced sourness and it compliments the lemongrass. If it goes more sour it might be too much. Does acetobacter with no oxygen @ 42F stay dormant?

On the side note in addition to acidity I smell & sense an aftertaste of barnyard. Isnt barnyard flavor / smell the product of Brett?

This is old acetobacter infection that I had and it looked similar.

 

[Yooper]

That sure doesn't look anything like aceterobacter infection! Mine vinegar has a "mother" but no scum like that.

Maybe lactobacillus, combined with a little brett? "Sour" usually means lacto infection, and will continue at cool temperatures.

 

[Pivzavod]

I taste vinegar type sour you find in Rodenbach. The beer was fine for 3.5 weeks but when I moved my Coopers to counter top I loosed up the lid so that I wouldn't have to twist hard and disturb the settled yeast & trub cake. The growth was very quick and I attributed that to acetobacter.

 

[theredben]

Doesn't sound like Acetobacter. Acetobacter needs oxygen to reproduce, and loosening up the lid would not introduce nearly enough oxygen to allow for enough Acetobacter growth that you would notice. Actetobacter infections were mainly encountered in commercial breweries with open top fermentors, using an airlock you purge the O2 out of the wort and the air.
To summarize, I also point the finger at Lactobacillus.

 

[DannPM]

If you have a barnyard AND a vinegar taste chances are you have quite a myriad of bugs in there vs just a specific culture of one or two.

 

[DannPM]

Ps use camden tabs vs temp to preserve bug characteristics when you're kegging, it's more reliable.

 

[Pivzavod]

Doesn't sound like Acetobacter. Acetobacter needs oxygen to reproduce, and loosening up the lid would not introduce nearly enough oxygen to allow for enough Acetobacter growth that you would notice. Actetobacter infections were mainly encountered in commercial breweries with open top fermentors, using an airlock you purge the O2 out of the wort and the air.
To summarize, I also point the finger at Lactobacillus.

I noticed the growth on top of the wort within 12 hours of moving the fermentor 15 feet from one side of the room to the other and loosening up the lid. Prior to that and for many weeks there was no indication of the bugs anywhere.

Why would any bugs wakeup if it wasnt for extra oxygen?

 

[ArcaneXor]

Brett usually forms bubbles. That looks like lacto to me.

 

[jonmohno]

I think its lacto too,ive had similar to this,white flakey skin on top. I racked under it,my bottles are fine currently ive had them bottled up and carbed at least 2 months and now they have been somewhat in cellar temps,i havent had anyproblems with taste or overcarbonation, i notice some of it in a few bottles or it seemed to be there for a while then disappeared in the bottle. I keep an eye on these few batches to look for gushers or anything weird tasting.I actually was starting to get a cloudy haze looking like it was forming on a california common,but i used s-23 lager dry yeast at too high a temp 68ish ambient during ferment,that had a off taste at first but turned out to clear up and be really good after a while. I noticed a film on the surface of the bottles in those for awhile. Those few batches that i had this stuff- i have segregated into tubs-just in case, i do think i need to drink them up before summer and it warms. They are sitting in the mid high 50's.(Basement floor)
Do you remember what temps you had the last week it was in primary. I only seemed to get this sitting in the higher 60's. I also think i need to change out my iodine solution in the airlock every week- i dont think it lasts 3 -4 weeks.

 

[Pivzavod]

I was using S05 and had it ~65-68F the whole time. It is definitely getting more sour now and its only been a few days in the fridge. In 5 days I dont taste the lemongrass anymore and sourness completely overtakes that part of the palate. Before I would taste sourness but there was a distinct flavor of lemongrass in the aftertaste.

Meanwhile @ Wikipedia:

Lactobacillus brevis is a species of lactic acid bacteria. It can be found in many different environments and in fermented foods such as sauerkraut and pickles. It is also one of the most common causes of beer spoilage. Ingestion has been shown to improve human immune function, and it has been patented several times.

L. brevis is one of the major Lactobacillus species found in tibicos grains (aka water kefir grains), and has been identified as the species responsible for the production of the polysaccharide (dextran) that forms the grains.[1] Major metabolites of L. brevis include lactic acid and ethanol. Strains of L. brevis and L. hilgardii have been found to produce the biogenic amines tyramine and phenylethylamine.

At least my immune system is better

 

[jonmohno]

Isnt that what you wanted? Doing lemongrass? Some wheats can tend to taste a little tart too,anyway

 

[Pivzavod]

Ive done the recipe before and it was not wheat sour. We are talking extreme sourness which was bacteria.

I also wanted to report that for some sourness mellowed down a little bit, maybe because I turned off co2 for a few days. Still drinking it.