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Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 11:31 am
by myerfire
On 19 October I started one of Scarecrow's vegetarian red lintel wash. It was a 9 gallon wash with 19.5 lbs of sugar. The specific gravity started out at 1.100 and lots of CO2 production for the several days. On the 23rd CO2 production had stopped, SG was at 1.020 and I added one tablespoon of bakers yeast. A little CO2 production and then it stopped again. Today, the 25th. SG is still at 1.020. Could the ABV be too high for the bakers yeast? If so, I guess I'll just distill it as is.
Recommendations, anyone?
myerfire

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 11:58 am
by Dnderhead
taste and see if it taste "dry" if it does run it.
( final sg varies depending what it was made of/what is still in it)

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 12:03 pm
by myerfire
I just tasted it and it tastes like a sweet wine. I have some Vodka Yeast, should I add some of that?
myerfire

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 12:08 pm
by Dnderhead
than is is not done, you can try the yeast or dilute the wash. how much sugar did you use?

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 12:10 pm
by myerfire
I used 19.5 lbs of sugar for a 9 gallon wash.
myerfire

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 12:43 pm
by rad14701
A potential ABV of 15.3% is a bit on the high side for bakers yeast... You may need to dilute the wash if you have room in your fermenter... Sounds like you've hit the ABV wall more than a lack of nutrients... You may also need to check your pH once you get the was diluted to a point where the yeast can ferment the rest of the sugar...

If you want to test my theory, aerate the wash to suspend any dead yeast... Then bring 2 quarts of wash and 1 quart of fresh water to a boil... Let that cool to 95F, aerate it well, and pitch some yeast... It should take off if the pH is acceptable and the fresh yeast will thrive on the boiled yeast in the wash... If this works then dilute the rest of the wash to about the same ratio and dump this starter in...

I was editing while you were posting... You may need to boost the pH a bit, too...

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 12:49 pm
by myerfire
I just checked the PH and it is between 3.5 and 4.0
myerfire

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 4:33 pm
by dixiedrifter
I don't think you killed the yeast, it just pooped out on its own... at this point i suggest running it cause nothing is going to get it started again.

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 6:25 pm
by myerfire
Dixiedrifter,
I think you are right, I added some Vodka yeast and it has nutrients mixed in, it's been about 5 hours now and still nothing in the way of CO2 production. I'm going to add a little "Sparkolloid" let it clear and distill it.
Thanks to all for your replys,
myerfire

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 6:32 pm
by Dnderhead
careful with that ,sugar is still in it ,and it can foam.

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 6:52 pm
by myerfire
Other than being careful, do you have any suggestions?
myerfire

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 7:09 pm
by Dnderhead
1) you can dilute and referment
2) you can distill as is but ,, do not fill boiler over 1/2-3/4 full . and when you bring it up to temperature , turn heat down "before" it reaches vapor temperature.so it does so slowly.

(you mite be able to use the spent beer for another ferment and save the suger)

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 7:15 pm
by myerfire
Dnderhead,
I think I will dilute it, put half into a fresh carboy. If I dilute it by 15% with water, should I add more yeast?
myerfire

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 7:32 pm
by rad14701
You need to back down further from that wall you've hit so fermentation can finish without as much stress on the yeast... Remember, you were at 15.3%+-, or and SG of 1.099... If you're at 1.020 that means you have about 20% of your sugar left and you don't want to hit the same wall... 25% - 30% dilution would be better...

Re: Did I Kill The Yeast?

Posted: Sun Oct 25, 2009 10:50 pm
by HookLine
Yup, dilute it at least 25%.

Re: Did I Kill The Yeast?

Posted: Mon Oct 26, 2009 7:20 am
by myerfire
OK, 25% it will be. 1.5 gallons of fresh water in a 6 gallon carboy and top off with my stalled fermented wash. I'm going to do this this morning and keep you posted. I assume the yeast is just dormant and I don't need to add more yeast.
myerfire

Re: Did I Kill The Yeast?

Posted: Mon Oct 26, 2009 9:18 am
by myerfire
I've got the batch devided and deluted by 25+% and after about 15 minutes I noticed some CO2 production again. So far, I'm a happy camper.
myerfire

Re: Did I Kill The Yeast?

Posted: Mon Oct 26, 2009 9:44 am
by rad14701
WOOT... :ebiggrin:

Sounds like you got the wash diluted before the yeast became too stressed... Let's hope...

Good luck...

Re: Did I Kill The Yeast?

Posted: Thu Nov 19, 2009 7:22 am
by Hillbilly Bill
Hope it's okay if I jump in with a question... just curious...
Using Lalvin EC-1118 or even the V-1116, what is the specific gravity at which the yeast absolutely cannot ferment? I usually run my fermentations with a beginning s.g. of around 1.05, but I have a buddy who swears he has fermented a batch that began at 1.20... what about it?

Re: Did I Kill The Yeast?

Posted: Thu Nov 19, 2009 7:59 am
by rad14701
Hillbilly Bill wrote:Hope it's okay if I jump in with a question... just curious...
Using Lalvin EC-1118 or even the V-1116, what is the specific gravity at which the yeast absolutely cannot ferment? I usually run my fermentations with a beginning s.g. of around 1.05, but I have a buddy who swears he has fermented a batch that began at 1.20... what about it?
An SG of 1.200 would ferment to the ~25%+ ABV range... Both EC-1118 and ICV-K1 (V1116) are rated by Lavlin to 18% ABV maximum, or an SG of under 1.130...

Re: Did I Kill The Yeast?

Posted: Thu Nov 19, 2009 10:34 am
by Hillbilly Bill
So... the fermentation process would not be hindered other than the fact that there would be excess sugar residue... is that correct? I guess that the yeast could probably thrive even in a very high s.g. environment... am I correct?

Re: Did I Kill The Yeast?

Posted: Thu Nov 19, 2009 10:39 am
by Hillbilly Bill
One more comment and I'm outta here. I don't want to get a rep as a hijacker. I know you are not a disciple of high alcohol washes, but if I am after neutral spirits using a reflux still, shouldn't I be starting my wash with a little higher s.g.?

Re: Did I Kill The Yeast?

Posted: Thu Nov 19, 2009 11:59 am
by rad14701
Hillbilly Bill wrote:One more comment and I'm outta here. I don't want to get a rep as a hijacker. I know you are not a disciple of high alcohol washes, but if I am after neutral spirits using a reflux still, shouldn't I be starting my wash with a little higher s.g.?
If you use more sugar than your yeast can handle then you're just wasting sugar and opening the possibility for off flavors and smells that you have to contend with... It's better to stay below the maximum potential a yeast is rated for so the ferments finish and do so cleanly... If you have a wash that has too high of an SG for the yeast the best thing to do is to split the wash into two fermenters and top up with water... Better to have two washes that can finish to half the ABV of a potential wash that won't finish at all... You'll be further ahead in the long run... Example: Two 12% ABV washes are better than one 24% wash, especially if the yeast die off before 18% because you're wasting the sugar to make another 6+%... The greed factor gets a lot of people in trouble, and not just novices...

Re: Did I Kill The Yeast?

Posted: Thu Nov 19, 2009 1:18 pm
by Hillbilly Bill
Thanks Rad...
Question... doesn't that pot get cold during the winter?

Re: Did I Kill The Yeast?

Posted: Thu Nov 19, 2009 2:53 pm
by rad14701
Hillbilly Bill wrote:Thanks Rad...
Question... doesn't that pot get cold during the winter?
I don't think it minds the cold as much as I do... :P

Re: Did I Kill The Yeast?

Posted: Thu Nov 19, 2009 6:34 pm
by HookLine
I guess that the yeast could probably thrive even in a very high s.g. environment... am I correct?
No. The higher osmotic pressure will kill them, or at least seriously stress them. The higher you go the more stress you place on the yeast, and the more off flavours they will produce.

A very good rule of thumb for beverage alcohol is to limit your ferments to no more than about 12% abv. Many, including me, do not go above about 10%. This is equal to 1 kg of plain sugar (sucrose) per 6 litres of ferment. (2.2 pounds per 6.34 US liquid quarts.)

We hobby stillers are far more concerned with quality than quantity. Many commercial distilleries also do not go above 7-8%.

Re: Did I Kill The Yeast?

Posted: Fri Nov 20, 2009 9:36 am
by Hillbilly Bill
Thanks Hook...
After weeks (months) of reading I have just about decided to quit using 1118 and 1116 in favor of baker's yeast. My wife bakes our bread and buying the yeast in volume would be a double benefit for us. I am still in the decision making process, but am leaning toward the change. I have always used a reflux still (mini-bok) but want to remove the packing and run it as a pot... I would like to try my hand at rum and brandy's.
Thanks again... you too Rad.
Bill