Yeast Question

[Kody_Wulfe]

Ok, so for one gallon of Mead... we use one pack of yeast.. is it a safe rule of thumb that for 3 gallons, use 3.. 5 gallons use 5??

I know.. weird question..

Kody

 

[Maylar]

Not weird at all. One packet is actually overkill for 1 gallon. For starting gravity of 1.100 or less you only need 1 gram per gallon. Yeast packets usually say one is good for "up to 6 gallons".

 

[Kody_Wulfe]

Thanks.. I was not sure.. I know there is a Science to it.. but I also realize that most it is also just experience and what works for someone....

Kody

 

[fossilcat]

I've always used one 5g pack for 1-2 gals, two for 3-4 gals, and three for 5 gallons. I've never done a bigger mead. Recently on this forum there was a discussion on aeration/oxidation which veered into talk about the lag phase. I think it was here that someone mentioned that yeast population can effect lag phase - the larger the yeast population, the shorter the lag phase. So even though you can ferment 5 gallons with a single 5 g packet, why make the yeast spend more time and effort to reach their alcohol producing population when you can do it for them? At 99 cents a pack, cost is not a factor. Less lag time, less stress on the yeast = better mead to my glass faster. Now I do 1 pack per gallon. I don't know what the overpitch threshold is but I'm sure this isn't close.

 

[bernardsmith]

Interesting question. Until very recently I would have argued that 1 pack is good for any volume between 1 gallon and 5, but Ricky over at Groennfell Meadery argues that with mead you really want to pitch far more yeast than you think you should - and that the more yeast you pitch (say, 5 packs for 5 gallons) the cleaner the mead will ferment and the sooner that batch can be bottled. You will also need to provide more nutrient. The irony is that the more yeast you pitch the LESS yeasty your mead will taste.

Groennfell publishes their recipes and by all accounts their protocol is quite different from the way that most home brewers may make their meads (they ferment at higher rather than lower temperatures (perhaps to ensure a more vigorous fermentation and a more vigorous fermentation helps ensure that any hydrogen sulfide produced by yeast is blown off and is not permitted to linger).
They sell their mead 3 -6 weeks from start to finish - and when you sell mead you are looking for customers to return.

 

[Kody_Wulfe]

The reason I ask.. is from all the reading I have done.. I have chosen to start all my meads as traditional... remove the lees.. then if I am going to add fruit.. do it then.. if I am going to flavor with extracts then just leave it as it.. I found a 5 gallon pail that I drilled for an airlock and I was going to brew a 4 1/2 gallon batch.. then decide if I am going to break it up.. or what when the time comes..

Kody

 

[fossilcat]

4 1/2 gallons of mead in a 5 gallon bucket may not be enough room when degassing.

 

[Kody_Wulfe]

Your right.. I think 4 gallons would be enough room?? yes??

Kody

 

[Baabaadoo]

If you had the time and really wanted to save some money, could you still buy one packet of yeast and just get a starter going? For those who want to save money, cumulatively it could help. Sugar, water, and nutrient in a glass erlenmeyer would do it, right? Could work up the population that way then pitch it when ready.

 

[bernardsmith]

Two questions and a thought:
1. Not an expert with starters but doesn't the starter and the must need to be close to the same gravity to avoid osmotic shock when you pitch the yeast?
2. Does the yeast population in a starter in fact increase.. or does the yeast in a starter simply have the chance to produce the sterols and enzymes they need to transfer the sugars through their cell walls?
And the thought: could you not create a pseudo-starter (and I am asking. I do not have the answer) by simply starting with one gallon of must and then when that has dropped close to 1.000, add another gallon of must, and so on until all 4 or 5 gallons of must is now fermenting.

 

[Maylar]

1. Starters are recommended to be 1.030 - 1.040 (according to White Labs)
2. You betcha. Population is what it's all about.

The last part of your question is similar to Scott Labs' restart stuck fermentation protocol. Make a starter and add must over time.

 

[fossilcat]

I tend to make a lot of assumptions, educated guesses, while making mead and then investigate later when time and opportunity affords. Re-hydration, starters, yeast population, are on the front burner with me right now. Here are my thoughts so far:

1. Scott Labs has an excellent detailed procedure in their handbook on re-hydration. It talks about atempering your yeast before pitch so you won't shock it.
2. Directions for using a smack pack suggest atempering around 68*-70* and pitch to 5 gals with an SG of up to 1.060. But recommends pitching additional packs if your must is colder or your gravity is higher. Nothing about acclimating, just pitch more. Maybe there's an acceptable kill rate?
3. Starters are lag time environments. Populations in a starter will reach levels dependant on available nutrician and must volume (maybe the same thing). In my opinion, what is often overlooked is that when the starter is eventually pitched, not only has the population increased, it has aged. It's not young anymore. No more young cell walls susceptable to "burning" by DAP. Maybe not as susceptable to osmotic shock either.
4. Starters reduce lag time, they don't eliminate it. But your starter population is hardier, and therefore, healthier.
5. I currently mostly believe there's no need to do starters for powder yeast if you can simply rehydrate more yeast if there's an acceptable kill rate, a die-off rate that won't affect the growth and sustainability of the population. $1 per 5gms packet vs $13 per smack pack. If I could justify it, I'd just buy more smack packs and forgo the starter.
6. What I don't mostly believe, and this is begining to bother me, is maybe starting powdered yeast is a good thing too. Even though there is an acceptable kill rate, the thing that killed them must be stressing at least some of the survivors. I know we're talking billions here, but millions of those is significant. If I could baby them through a starter and acclimate them as bernardsmith suggests, reducing stress even more, wouldn't I have a better mead?

 

[bernardsmith]

The thing about starters - when used with a stir plate - is that you are in fact adding some oxygen in at the start (not a huge amount, I would think, and nothing like the amount you would add if you used one of those sintered stones attached to an O2 pump, and perhaps even significantly less than you might add if you shook the bejesus out of a 2/3 full carboy...) but you are certainly providing the yeast with O2 as it enters the world of fermentation..and providing that O2 continuously as the yeast remains in the starter for what? the day? two days? of lag time so that when you pitch the yeast slurry it will take off like a rocket.

 

[Drewed]

All yeast, including smack packs and test tubes are in a state of "limited activity." A starter, or a proper re-hydration, allows the yeast time to "wake up and get ready to work." Its the difference between waking up slowly to a nice hot breakfast or having a bucket of cold water dumped on you.

 

[Kody_Wulfe]

Ok you two.. way out of me league..HEHEHHE

Kody

 

[Kody_Wulfe]

I never understood harvesting the lees to keep yeast... or am I not understanding something...

Kody

 

[Lefou]

We've had similar discussions in the beer forums regarding yeast and starters, cell counts, and pitch rates. From what I understand, there are more than enough yeast cells in an 11.5gram packet to sufficiently inoculate 5 gallons of beer wort at a gravity of 1.050. I use White Labs liquid yeast for the most part and even the directions state making a starter for musts or worts over 1.050. Just to educate myself on "why", I bought Chris White's book co-authored with Jamil Zainashef AFTER getting Ken Schramm's "Compleat Meadmaker".

I started making mead before making beer and wish it had been the other way around. Those two works are some of the best books you can find on mead, beer, and yeast.

 

[jan_b19]

1 gram of yeast contains about 10 billion to 20 billion yeast cells, some yeast have higher cell count some a bit lower so 10 is a nice average.
As long as you're making less than 5 gallons and the OG of your must isn't higher than 1.130 one package is plenty. When your OG is over 1.130 I would consider making a yeast starter or pitching 1.5 to 2 packages for 5 gallons.
the minimum: for moderate gravity (up to 1.100) 1g/gallon, for medium (1.115) 1.2g/gallon and for high (1.130 and up) 1.5-2.0g/gallon. But it doesn't hurt to pitch by a factor of 2 if you want to be sure.

 

[Baabaadoo]

According to an article I read about optimizing honey fermentation, “Yeast produce 33 times as much alcohol per cell during the growth phase than it does in the stationary phase."

This mean that a yeast starter would bypass the most productive phase of alcohol production?

 

[Drewed]

No, as the same amount of alcohol would be produced, it would just do it in a shorter amount of time.

I like to think of yeast as people. Say you have a big job to do, say picking a corn field by hand. If you have 10 people out there picking, they will get the job done, but it will take a log time, and they will ***** about it, and they will probably do a crappy job at it because you made them work too hard. Now take that same field and put 1000 people in it. They will finish much faster, and having worked not as hard will be happier, and will have not complained about it.
I could take this farther with the first ten workers you dumped them out of their beds right into the field, and then demanded that they also go find enough friends to have a total of 2000 workers.

Yeast are living things, treat them nice and they treat you nice.

 

[Baabaadoo]

Good point. The article doesn't mention stress.

 

[jan_b19]

According to an article I read about optimizing honey fermentation, “Yeast produce 33 times as much alcohol per cell during the growth phase than it does in the stationary phase."

This mean that a yeast starter would bypass the most productive phase of alcohol production?

No, You're making a yeast starter to have enough cells to have a healthy and reasonably fast growth phase. But that amount of cells isn't even close to the amount of yeast cells after the growth phase. The reason you want a healthy amount of yeast cells is to avoid other organisms to start fermenting or worse infecting your must (while the yeast is still weak), and because yeast produces CO2. CO2 is heavier than air and it will put a nice blanket above your must to protect it from oxidation.
Pitching too little yeast also stresses the cells. Stressed takes a long time to ferment and gives a unwanted flavor to the final product.

 

[Baabaadoo]

As I mentioned in response to Drewed, I didn't take into consideration stress. He stated most of what you said, but in an analogy format.