Rehydrate your yeast
For those of you that use dry yeast, you must rehydrate your yeast before pitching. When dehydrated, the yeast’s cell membrane is highly permeable; it allows just about anything to pass through. If you just toss your dry yeast into the wort, you will get all sorts of simple sugars inside the yeast. This will effectively kill off a large number of your hapless yeast.
Rehydrating yeast in boiled water that has been allowed to cool to about 70-80 degrees will allow the cell membranes to “puff out” and regain their ability to act as a chemical filter. Taking some extra time will increase your pitch rate and give your beer a head start.
Happy Brewing!
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Interesting, I have never heard this explanation about sugar entering the membrane. I have tried both approaches, and have found that not rehydrating is easiest, and safest… and it works. When rehydrating, I somehow lose a bunch of yeast, and am paranoid about contamination. With pitching the yeast dry, I have virtually no worries about contamination, and the fermentation tends to start off quickly.
Where did you hear about this?
cheers!
If you rehydrate your yeast using bottled water or water that has been sanitized through boiling ( and allowed to properly cool ), you won’t have any sanitation issues. This advice came from Jamil from the Brewing Network. I have also heard similar advice from commerical brewers during interviews on the same program.
You can get away with just pitching dry yeast, but your initial cell counts will be a lot better if the yeast is properly rehydrated.
In truth, you should do much more than just rehydrate your yeast; you need to create a yeast starter. It is basically a very small scale batch of beer that allows the yeast to begin reproduction before pitching into primary batch of wort.
I always create starters for my liquid yeasts, but never do for the dry ones. This is for three reasons.
1. The cell count on a dry pack is HUGE compared to the liquid cultures, typically there is no need given the gravity of my wort.
2. The dry yeast have some kind of food storage set in, and creating a starter would force the yeast to consume it (if I can remember correctly), and this is a bad thing.
3. Good dry yeast packets (US-56 or S-04) are so cheap I can buy a few packets for the price of a liquid pack.
check out jamils website (you probably already know it) http://www.mrmalty.com
I might do some experiments dry pitching the dry yeast, vs rehydrating, and see if there are any differences. I can say one thing, I dry pitched my last US-56 and there is a large amount yeast cake on the bottom. But, the difference might be in the flavor.
cheers!