Brettanomyces?

[David Violante]

I had this in my Black Grapes postings but I think it might belong here in equipment sanitation.

The opportunities for learning continue… So I have 3 demijohns, and one each 3-gallon and 5-gallon carboy of black grape wine (I posted a lot of the process in that thread). The demis seem to be doing ok, as does the 3-gallon. Two weeks ago I looked at them all and the 5-gallon had small bubbles going and I thought, MLF? Odd given the SO2 routine but ok.

Then I looked a few days ago and I doubt it’s MLF. I’m thinking Brettanomyces. Below are pics of the top of the wine and microscopy. No idea how, but here we are. I clean and sanitize well, and sparge headspace with nitrogen. So, I double dosed with SO2 and added Bactiless 1g/gallon, and dropped the pH from 3.7 to 3.4. The wine tastes ok and there are no off flavors or smells (from the middle of the carboy).

I have three questions: 1) does this seem like enough treatment, 2) what’s the best way to clean and sanitize the items that have been in contact with the wine (plastic sampler and cylinder, silicone bung) so as not to contaminate anything else, 3) should I prophylactically treat the remaining wine from this lot?

 

[VinesnBines]

It looks more like mycoderma. I think wipe off the film with a paper towel soaked in strong kmeta solution (sanitizer level). Add a double dose of kmata and a bit of grain alcohol on the surface.

If Brett, I understand you can smell the bandaid odor or barnyard smell. If you suspect Brett, I would toss the plastic ware and clean anything you think about using for wine with lye.

Personally I would burn the winery and move 50 miles. Probably not practical if you are making wine in the basement or garage. Seriously, until you rule out Brett, retire the equipment.

 

[David Violante]

Ok, I’ll isolate the equipment and burn the winery… 50 miles may not be enough… seriously though, I didn’t smell bandaid or barnyard. I did double dose and swipe with a sanitized KMeta paper towel. I’ll add some grain alcohol as well. Thank you! I’ll post any changes.

 

[Rice_Guy]

Organisms that cause infection are endemic. We control them in part by changing the environment so that it is not conducive to growth. I could not say what this is without running isolation tests in the lab. In my setup I have lots of apple which means malic acid which can be metabolized by several organisms classed as wild lactic acid bacteria (LAB).

* If you have a chronic infection, look at replacing everything that is a plastic tube. If you can brush clean as stainless pot or glass carboy I would give a good cleaning with warm / hot soap water then oxidizing agent. Equipment with wood is avoided since the pores trap bacteria and protect them from contact with chemical cleaners. Stainless is expensive, we don’t toss it to fix a process, we replace all rubber gaskets then clean.
Is this a one shot issue?
* pH is a control for many micro families. In essence the traditional way to control apple infection at 5% ABV was to keep the pH below 3.5, better yet put it at 3.3 or 3.2. Some cyser I have run gets acid addition after the primary to drop the pH when I am cleaning it up, this then needs back sweetening to compensate. ,,, pH is one of the few traditional control methods.
* Pasteurizing, heating to 140F is traditional. Finished product control. I have used it a handful of times, note with low ullage wine expands enough to push over a cap. Beer controls infection with heating prior to fermentation, heating pH 4 at boiling for 40 minutes is all we need for acid foods.
* There are two micro control products to look at, Lysozyme and Bactiless. They will control LAB infection without pH intervention or dropping the pH. My feel is that they work better below pH 3.5, above 3.5 I still see pH drift upward.
* What is your free SO2 regimen? You are more effective if you come out of the primary with a target of 75 or 100ppm and plan for a reduced second racking treatment. Do you measure?

All in all you could look at what beer folks do. Alcoholic beverages are a preservative system. We build layers which exclude families that require oxygen and tolerate SO2 and pH and free sugar etc. By having a lower barrier in one area we need a higher barrier some place else. Good luck.