OPEN FERMENTING???

[007sniper]

im stepping up from my 5 gal set up to a 30 gal was wondering about open fermenting? my old fermenters were 5 gal buckets with a home made air lock. but i picked up on some plastic, 30 gal blue barrel w/o lid. ive seen pics of fermenters with cheese cloth over them.

so heres my question. just wondering if i have to increase the amount of yeast when using the open fermenting method? or just use the same ol recipe ive been using? and if it takes longer to ferment the open method? ( befor you tell me about the temp?? its all done indoors so fermenting temp will always be the same )

tanks in advance, SNIPER

[Braz]

Some wine makers actually prefer to open ferment for the first 2-3 days. They say it allows the yeast access to oxygen during the aerobic phase. I am a little skeptical but, maybe.

You can cover your barrel with saran wrap, or a plastic trash bag using a big rubber band (or something) and just poke a pinhole in it to let the gas out.

[BigPa]

I ferment UJSSM in a 30 gallon open top covered with a bath towel. Never had any problems...

[Lawrenceburg Native]

The main concern is to keep fruit flies, birds, etc. out.

[rtalbigr]

I'd put some kinda cover on, just to keep nasties out, doesn't have to be air tight.

Big R

[007sniper]

i am going to cover it with cheese cloth and a rubber band.........
the thing i was wondering about is will it take longer to ferment?
and do i need more yeast than usual?
just dont want to waste a wash if i can help it.

[Washashore]

However much yeast you used for 5 gallons, multiply by six and you should be fine.

[RumBrewer]

i am going to cover it with cheese cloth and a rubber band.........
the thing i was wondering about is will it take longer to ferment?

You may actually experience a SHORTER ferment time.
Yeast have a few stages of life (Don't we all) and one of them is their aerobic phase. This is when they eat oxygen and reproduce. Eventually, the available o2 is used up and they begin to eat sugar. This is when they make alcohol. But with an open fermenter, the o2 will be extended, theoretically giving you a longer aerobic phase, more viable yeast cells and thus a shorter ferment. The trick is keeping everything ELSE out of there before the yeast drop the pH and increase the alcohol to a safe level to prevent infection.
Cheese cloth seems to work ok, and it's not like nobody ever distilled an infected wash.
Have fun with it and let us know real-world results!

[Washashore]

i am going to cover it with cheese cloth and a rubber band.........
the thing i was wondering about is will it take longer to ferment?

You may actually experience a SHORTER ferment time.
Yeast have a few stages of life (Don't we all) and one of them is their aerobic phase. This is when they eat oxygen and reproduce. Eventually, the available o2 is used up and they begin to eat sugar. This is when they make alcohol.

Just to clarify, the yeast don't actually "eat" sugar. They "eat" the nutrients that we provide for them in the wash while they dismantle the sugar molecules into ethanol and CO2 (as well as other alcohols and congeners)

[007sniper]

thanks for the info.

[Washashore]

I just found this on the parent site:

You can find this HERE

To use the best brewing guidelines- use 2 to 4 grams of dried yeast per gallon of mash.
If the alcohol is in the 5% or less range - use 2 grams per gallon.
in the 5 to 7%abv range; use 3 grams per gallon.
In the 8 to 10%abv range use 4 grams per gallon.
You will know when you have pitched the right amount of yeast because the high kraeusen stage (the tall foamy cap) will have formed in four hours or less. If it takes longer than 4 hours- don't worry too much. If it takes longer than 24 hours to form- you aren't using enough yeast.

Higher than 4 grams per gallon will get you some sulfur flavors that can be hard to get rid of, so only use the 100 grams of dry yeast per 5 gallons (20 litres) rule for a pure sugar mash that is destined to be carbon polished and turned into vodka or a "base spirit" for liqueurs, etc.

[RumBrewer]

Just to clarify, the yeast don't actually "eat" sugar. They "eat" the nutrients that we provide for them in the wash while they dismantle the sugar molecules into ethanol and CO2 (as well as other alcohols and congeners)

<Sigh> I am going to have to keep an eye out for you... aren't I?

[Fourway]

unless your work area has nasty stuff living in it or you are starting with raw product with nasties hitching a ride a slow start isn't the end of the world... but neither is over pitching. I've done some wild yeast ferments and they usually start slow... if there isn't anything around more aggressive than the wild yeast then the yeast wins. if you have an aggressive infection floating around you can go the other way and overpitch massively... the off flavors associated with a heavy hand on yeast are often cleared up just by having bright copper in the vapor path.

I've never had a fruitfly come through the still no matter how many were in the boiler... it seems they aren't volatile.

[Washashore]

Just to clarify, the yeast don't actually "eat" sugar. They "eat" the nutrients that we provide for them in the wash while they dismantle the sugar molecules into ethanol and CO2 (as well as other alcohols and congeners)

<Sigh> I am going to have to keep an eye out for you... aren't I?

didn't mean any offense....just a clarification...that's all...we're all brethren here

[Washashore]

I've never had a fruitfly come through the still no matter how many were in the boiler... it seems they aren't volatile.

Ha ha ha....now that's funny!

[Lawrenceburg Native]

I've never had a fruitfly come through the still no matter how many were in the boiler... it seems they aren't volatile.

That may be true. But the vinegar that may be created as a result of them in the batch is certainly volatile.

Fruit flies can be a vehicle for Acetobacter aceti. This bacteria is plentiful in the environment and converts alcohol to acetic acid (vinegar).

II. IDENTIFICATION AND TAXONOMY
A. Overview
Acetobacter aceti is a Gram negative bacterium which is motile by peritrichous flagella. It is obligately aerobic possessing only the ability for respiratory metabolism with no fermentative ability. A. aceti does not form endospores. This bacterium is ubiquitous in the environment, existing in soil, water, flowers, fruits, and on honey bees; in essence, wherever sugar fermentation is occurring. A. aceti produces acetic acid from ethanol in alcoholic niches in the environment. Acetate and lactate are oxidized to CO2 and H2O by the organism. The optimal temperature for growth is between 25 to 30C, and the Ph optimum between 5.4 to 6.3 (De Ley et al., 1984). A. aceti is a common contaminant in all industrial fermentation facilities and is responsible for generating turbidity, ropiness, discoloration, and off-flavors in beer (Kough, 1991).

sources:
http://epa.gov/biotech_rule/pubs/fra/fra001.htm" onclick="window.open(this.href);return false;" rel="nofollow
http://www.squidoo.com/acetobacter" onclick="window.open(this.href);return false;" rel="nofollow

Maybe a sour mash with a low enough pH will help prevent proliferation of this bug.

-LN

[Washashore]

So by keeping the mash/wort anaerobic, the bacteria can't survive?

[RumBrewer]

So by keeping the mash/wort anaerobic, the bacteria can't survive?

sorta.
Acetobacter (Used for making vinegar at my house) needs o2 to do it's thing. It creates a little funk, but without plenty of oxygen it really can't convert alcohol to acetic acid (Vinegar).

[frozenthunderbolt]

II. IDENTIFICATION AND TAXONOMY
A. Overview
Acetobacter aceti is a Gram negative bacterium which is motile by peritrichous flagella. It is obligately aerobic possessing only the ability for respiratory metabolism with no fermentative ability. A. aceti does not form endospores. This bacterium is ubiquitous in the environment, existing in soil, water, flowers, fruits, and on honey bees; in essence, wherever sugar fermentation is occurring. A. aceti produces acetic acid from ethanol in alcoholic niches in the environment. Acetate and lactate are oxidized to CO2 and H2O by the organism. The optimal temperature for growth is between 25 to 30C, and the Ph optimum between 5.4 to 6.3 (De Ley et al., 1984). A. aceti is a common contaminant in all industrial fermentation facilities and is responsible for generating turbidity, ropiness, discoloration, and off-flavors in beer (Kough, 1991).

sources:
http://epa.gov/biotech_rule/pubs/fra/fra001.htm" onclick="window.open(this.href);return false;" rel="nofollow
http://www.squidoo.com/acetobacter" onclick="window.open(this.href);return false;" rel="nofollow

g.

-LN

Given that they are gram negative, perhaps fermenting in a copper pot would inhibit growth of the vinegar bug due to the oligodynamic effect of copper?

2959-10190-1-PB.pdf

(90.19 KiB) Downloaded 158 times

[Fourway]

I just go "Oh Damn! Flies!" And get it in the still in a big hurry.

[brewmasterDan]

I've never had a fruitfly come through the still no matter how many were in the boiler... it seems they aren't volatile.

Ha ha ha....now that's funny!

Fruit flies themselves are not volatile but do cause a volatile reaction when your wife whacks you over the head with a frying pan due to your 100 new friends buzzing around in her kitchen.

[RumBrewer]

Great Pick of the open fermentors at the St. Lucia distillery.
Also, some cool picks of their pot stills at http://www.Rumconnection.com" onclick="window.open(this.href);return false;" rel="nofollow

[Washashore]

Cool pics.... Damn that looks messy though. I wonder why they top them off so high.

[Pop Skull]

Some wine makers actually prefer to open ferment for the first 2-3 days. They say it allows the yeast access to oxygen during the aerobic phase. I am a little skeptical but, maybe.

You can cover your barrel with saran wrap, or a plastic trash bag using a big rubber band (or something) and just poke a pinhole in it to let the gas out.

With red wines we made this harvest we had covers over the fermentor tanks, but they were more to keep stuff from falling in than anything else. The yeast were pushing out so much CO2 that the wine is pretty much protected. Reds are more resistant to oxidation than are the white wines, which will be fermented in closed top tanks and the like.

With the reds it's also good to have access to the top of the cap, so that the skins pushed to the top by release of CO2 can be punched down - that helps reintroduce oxygen into the wine as well as helping to extract flavor and aromatic compounds from the skins up top.