Question about yeast

[Arturo Mustelier]

Hi. I would like to know something about the small yeast envelopes that are good from 1 to 5 gallons of wine. If I am making 5 gallons but in separate 1 gallon jugs, should I divide the envelope content in 5 parts, or does it mean that I should use an entire envelope the same for 1 gallon than for a 5 gallons pail or carboy? Thanks in advance!

 

[meadmaker1]

I suppose you could split it up.
I don't think I'd go more than 1/2 . But yeast is $1. So I've always used full package.
If it where tougher to get or I had to wait for more I would make a fair sized starter.
I like to hydrate and make a starter either way so a 1/2 gallon starter instead of a qt. And it would be easier to divide

 

[Arturo Mustelier]

Keith, then your advice would be (based on your own experience) a full envelope to each gallon?
I can get the yeast pretty easily and I am not a cheapskate either lol, but I was concerned about using too much yeast in one gallon if I used the whole package. Thank you!

 

[Stressbaby]

Most everyone here will probably tell you it's OK to use the entire packet for 1 gallon batches.

I'm a contrarian. For my 1 gallon batches I only use 1/2 packet of yeast. When using 1 packet/gallon I find it more difficult to control the fermentation speed and temperature; and particularly aromatic wines, I lose some of the character of the fruit as a result of faster, hotter ferments.

 

[salcoco]

to use less than the whole packet purchase a small gram scale. one gram yeast per gallon is sufficient. make sure to hydrate per instructions on the packet. take unused yeast and refrigerate ready for the next batch.

 

[meadmaker1]

Keith, then your advice would be (based on your own experience) a full envelope to each gallon?
I can get the yeast pretty easily and I am not a cheapskate either lol, but I was concerned about using too much yeast in one gallon if I used the whole package. Thank you!

I am a cheapskate not that money is an issue i just dont like to spend more that i need to, on things i don't really need,.
As far as a packet being too much, i dont see that as likely. The yeast is going to multiply at a crazy rate either way so in several hours there will be far more yeast than the little bit in the package.
I have to go to work now but latter i will look for the info i have found in the past regarding yeast reproduction and post it if i can find it again.

 

[BernardSmith]

But here is the thing: sure yeast will bud and reproduce and they do that rapidly but it is not clear that daughter cells are going to ferment your must as well as a larger colony of mature cells and it is unclear that pitching a small colony of cells into a large pool rich with sugar will not result in flabby, lazy cells that fail to ferment with sufficient vigor (not speed) to expel odors that may be less than desirable. I am not a chemist and not a dietician.. but I am sure you are familiar with published "portion sizes" (1/2 cup of cooked pasta is a portion?). You cannot under ordinary circumstances over-pitch yeast but you can under-pitch. I would treat one gallon to one pack of yeast. and if you are worried about the "speed" of the fermentation then lower the temperature. What you want is a vigorous fermentation , not a fast one, and you want that fermentation to be clean. If your starting gravity is around 1.090 or higher I don't see how you can get that with less than 1 pack per gallon (assuming your rehydration protocol is top notch and you are pitching a high percentatge of viable yeast cells and not killing about 50 % of the cells before they have rebuilt their cell walls

 

[Stressbaby]

But here is the thing: sure yeast will bud and reproduce and they do that rapidly but it is not clear that daughter cells are going to ferment your must as well as a larger colony of mature cells and it is unclear that pitching a small colony of cells into a large pool rich with sugar will not result in flabby, lazy cells that fail to ferment with sufficient vigor (not speed) to expel odors that may be less than desirable. I am not a chemist and not a dietician.. but I am sure you are familiar with published "portion sizes" (1/2 cup of cooked pasta is a portion?). You cannot under ordinary circumstances over-pitch yeast but you can under-pitch. I would treat one gallon to one pack of yeast. and if you are worried about the "speed" of the fermentation then lower the temperature. What you want is a vigorous fermentation , not a fast one, and you want that fermentation to be clean. If your starting gravity is around 1.090 or higher I don't see how you can get that with less than 1 pack per gallon (assuming your rehydration protocol is top notch and you are pitching a high percentatge of viable yeast cells and not killing about 50 % of the cells before they have rebuilt their cell walls

One half of a 5g packet far exceeds the standard dose rate of 1g/gallon.
Someone more familiar with the kinetics of fermentation would have to help here. I'm just saying my purely anecdotal experience is that for some aromatic wines, 5g/gallon results in fast hot ferments (ie, 3 days) which cause the wine to lose some of its character. Now off to google scholar...