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Dan McFeeley
01-12-2005, 03:50 PM
I might have shocked some of the yeast (2 pkgs). I didn't pay attention to the temperature until after I pitched it (noob mistake). One packet should be fine though. I areated the must by stirring it (alot), and also pouring the must into the fermenter through a small spout from my brewpot.

Although this is a different thread, I stuck Deege's post here because, if the mead doesn't start soon on its own, a possible problem may have been rehydrating the yeast.

Here's some tips from the Lalvin site -- take a look!

http://consumer.lallemand.com/danstar-lalvin/lalvinrehyd.html

http://consumer.lallemand.com/danstar-lalvin/InFerment/Clayton_Hints.html

Lagerman64
04-13-2005, 10:16 AM
Does it really matter? I haven't noticed any difference between rehydrating and dumping in dry. I generally have the same lag times, could just be me or my fermenting environment. Ideas?

Jmattioli
04-13-2005, 12:35 PM
Does it really matter? I haven't noticed any difference between rehydrating and dumping in dry. I generally have the same lag times, could just be me or my fermenting environment. Ideas?

Good observation Lagerman,
Some always pitch it dry with no problems and the 15 minutes makes little difference. However that being said, here is the reasons I would give for rehydrating yeasts where it is recommended by the manufacturer.

Some start at very high SG's and this creates a problem for most yeasts as they take in a relatively tremendous amount of liquid in their cell wall while rehydrating. This high sugar must can effectively poison many of the yeast. Thats why they recommend you rehydrate in plain water for 15 minutes. After that further rehydration is just a waste of time. This rehydration makes the acclimation of the yeast to the solution less stressful so be nice to your yeast. Look at it like you getting a glass of fresh water before swimming in the ocean salt water. You are fine as long as you don't start drinking the salt stuff first.

Remember, not all yeasts are created equal. With Beer, I never rehydrate yeast and have never had a failure. (always use fresh yeast) But then again beer is a low starting SG. Not to terribly stressful on rehydrating yeast. Mead, on the other hand as you know from posts here have people who start them out on massive does of honey (sugar) which makes rehydration first more important for a quick fermentation.

So, although you might not notice a difference with your starting SG's. You will have more problems in the long run with different recipes if you don't rehydrate first.



Joe

toolboxdiver
04-13-2005, 07:04 PM
Does it really matter? I haven't noticed any difference between rehydrating and dumping in dry. I generally have the same lag times, could just be me or my fermenting environment. Ideas?



Personaly I use a yeast starter and pitch that into the must, guess its just a matter of personal opinion

Oskaar
04-13-2005, 11:15 PM
I rehydrate as per the Lalvin spec. Basically they explained it to me as Joe articulated below. Must is not the best environment for yeast that is coming from a freeze dried state into a thriving living colony. Water is a better and more neutral environment for the yeast to wake up in.

If your yeasties wake up stressed, their progeny will not be the ideal uber-yeasts that you hoped and prayed they would grow up into. Sub-par yeast kids from stressed out parent yeast will not ferment as aggressively, completely and quickly as they should, and there is an elevated risk of off-flavors and H2S. Oh the humanity!

Cheers,

Oskaar

Lagerman64
04-14-2005, 01:32 AM
Very good points indeed. Thanks for clarifying. :D

Miriam
04-19-2005, 12:48 AM
I'm thinking about all the advice I've seen to rehydrate yeast in warmed must, in orange juice, in water with sugar added. (There are also elaborate yeast preparations for highly acidic musts such as hard lemonade, where feeding the yeast in several stages and maintainance of warm temperature throughout is crucial.) As a breadbaker, I've always observed that the old theory of adding a little sugar to the yeast and water does work; the yeast activates more quickly with that nutrient.

But now those more experienced than I seem to be saying that wine yeast and water alone do the trick better. I have to say that my yeast preparations with warm must or orange juice have always given me vigorous, foaming and fizzing fermentation. You should pardon the alliteration ;D

So is there a contradiction?

Miriam

hedgehog
04-19-2005, 01:10 AM
My two cents...
I honestly don't think there is a contradiction, more like a bending of the rules. Supposedly the yeast growers prepare their yeasts for their nap and wake up so that the optimal rehydration and waking up of the yeast occurs in only warm water. (Insert all kinds of really UGLY organic chemistry here.. ) So using only warm water, you are "optimally" rehydrating and waking up your yeast.
But in the same token, "optimally" you should use wine yeast in your mead, but Joe's ancient orange uses bread yeast and still is awesome. Optimal, no, but it works and works really good. :D
So when people use starters or dump their dry yeasts directly into a must, they are not "optimally" rehydrating them. But if it works, it works... and I am sure that someone will volunteer to deal with the tasty consequences.
course personally, I try to rehydrate my yeast in a glass of only hot water. Mostly because I know from my wilder days that if someone tries to feed me while I am still asleep and I wake up with french fries up the nose or ketchup in my hair, i wake up REALLY grumpy.. so I definately don't want to do that to the yeasts... ;)
just my 2 cents..
hedgehog

Jmattioli
04-19-2005, 08:58 AM
(snip)
But now those more experienced than I seem to be saying that wine yeast and water alone do the trick better. I have to say that my yeast preparations with warm must or orange juice have always given me vigorous, foaming and fizzing fermentation. You should pardon the alliteration ;D

So is there a contradiction?

Miriam

No contradiction. All yeasts are not the same. The manufacturer of the yeast will give you the best advice and Lalvin says rehydrate first in plain tepid water or they give the temperature range. After 15 minutes you can pitch it in a starter or the mead must. Will it work without following their exact instructions? Of course it will in most cases. But not in all. And they usually know best since they have a controlled laboratory to experiment in. So, do what you want but unless you prove that in all cases (various SG's) your method is best, it is best to recommend what the manufacturers do, so the new people starting out will not encounter more problems in the long run.

I am very unorthodox in some of my methods but I usually put a disclaimer on it cause what I do with some yeasts in certian meads are not an acceptable practice for all meads. I also add large amounts of acid up front in certain English type meads but I would not recommend that people take up that practice and it can result in a lot of stalled meads. I would recommend they add it at the finish. So you see it is best to follow accepted and recommended proven practices unless you are experimenting on your own and have an understanding of the ramifications of your method.

Joe

Miriam
04-19-2005, 10:07 AM
HH and Joe,

I guess the blinders over my eyes are the fact that I use exclusively Red Star yeasts as only they, as far as I know, are kosher. At any rate, only Red Star is available here. The instructions say to rehydrate in water. Well, I'm going to try it that way next time, instead of stuffing the yeast with perhaps unwanted nutrients right off.

My vision is not that of a collegiate prank but of Mamma tenderly bending over the yeast starter jar and urging the yeasties to "Eat, eat, my darlings..."

Miriam (who never said that to her kids in her life, they'd take her head off) ::)

Dan McFeeley
04-19-2005, 02:19 PM
. . . My vision is not that of a collegiate prank but of Mamma tenderly bending over the yeast starter jar and urging the yeasties to "Eat, eat, my darlings..."

Miriam (who never said that to her kids in her life, they'd take her head off) ::)

Maybe we just need to broaden the motherly scenario a bit. Mamma says to her yeasties "Are you ready for dinner? Have you washed your hands?" when it's time for rehydration. After the yeasties are properly washed, i.e., rehydrated, and ready for the honey must, *then* it's "Eat, eat, my darlings." ;D ;D ;D

Miriam
04-19-2005, 02:29 PM
There you go, everything depends on how you look at things.

True, true; I do always make everyone wash their hands... :D

Miriam