Pitching Dry Yeast v. Rehydrating

Discussion in 'Homebrewing' started by CCW, Oct 1, 2012.

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  1. CCW

    CCW Initiate (0) May 14, 2012 California

    I am making my first attempt at homebrewing this weekend with a honey nut brown ale. I have safale us 05 ale dry yeast. I have read that some people directly pitch the yeast into the wort and that some prefer to rehydrate via a yeast starter before they pitch it as they believe you loose a substantial amount of yeast cells. From what I've read it seems that rehydrating the yeast is the way to go but I'm curious to know what everyone's experiences and results have been using either method. Happy Brewing and cheers!
     
  2. Tebuken

    Tebuken Initiate (0) Jun 6, 2009 Argentina

    There is no need to make a starter, just boil 110 ml for 11 grs dry yeast,let it cool to 96 F then add yeast and wait 15 min.That´s the way yeast is rehydrated.After 15 min you could stirr it up with a sanitized spoon and dump to fermentor.It is always preferable to rehydrate before pitching.
     
  3. kaips1

    kaips1 Initiate (0) Feb 20, 2011 Kentucky

    either way works, depending on how many living cells are in your packet and your brewing efficiency there shouldnt be a problem pitching it straight, I tend to make starters these days because i can time it pretty right and will get activity in my airlock by the time i go to sleep on brew day.
     
  4. luisfrancisco

    luisfrancisco Zealot (606) Dec 1, 2009 Mexico

    I used to rehydrate until I started just dumping the dry yeast packets into the fermentor and saw no change at all. When I use liquid yeast, then I'll make a starter, but not for US-05.
     
  5. VikeMan

    VikeMan Grand Pooh-Bah (3,043) Jul 12, 2009 Pennsylvania
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    Rehydration is not the same as making a starter. You probably know that, but I mention it for the OP.

    OP: by some estimates, you'll lose half of your otherwise viable cells by pitching dry yeast without rehydrating. Rehydrating is what Tebuken described. (A starter is something else, and is not generally recommended with dry yeast, for reasons you really don't need to worry about for your first batch, since you are using dry yeast.).
     
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  6. jtmartino

    jtmartino Initiate (0) Dec 11, 2010 California

    Can you explain why this is the case?
     
  7. hopfenunmaltz

    hopfenunmaltz Pooh-Bah (2,611) Jun 8, 2005 Michigan
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    Dry yeast has the cell membranes full of sterols so they can reproduce for many generations. Dry yeast also has about 20 billion cells/gram so there are 220 billion cells in a fresh 11 gram pack vs 100 billion for liquid yeast. Not much need for a starter.
     
  8. VikeMan

    VikeMan Grand Pooh-Bah (3,043) Jul 12, 2009 Pennsylvania
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    Basically dry yeast is cheap, and comes with more cells per package. And even if you need more cells than come in one package, it's cheaper and easier to pitch two packages than to make a starter.

    Also, at least one dry yeast manufacturer stresses that their yeast is dried in an optimal ready-to-go state that you shouldn't mess with.
     
  9. beer272

    beer272 Initiate (0) Sep 23, 2009 New Jersey

    I have used dry yeast to date. May change when I go towards AG. I have re-hydrated a couple of times, and more times just tossing it into the wort. I have even drank one of my beers out of glass, then swirl the remnants in the bottle and pitch with just that. That works too, however that slows down the ferment start time. These days I am making starters with bottle dregs.
     
  10. MLucky

    MLucky Initiate (0) Jul 31, 2010 California

    Whenever you ask a question like that around here, you will always hear from people on both sides who say their beer comes out great. And that's probably true: beer can be pretty forgiving. But in my mind brewing is all about adopting the best practices and doing things right, and in this case that would be rehydrating. If you don't, you will indeed lose cells, and you will have a less than ideal pitch rate. The yeast will still make beer, but they'll be more stressed, and that can result in off flavors.

    One thing that can be a little tricky for a first-timer: you want to pitch the yeast roughly 15 minutes after it's been rehydrated. If you wait longer, the rehydrated yeast can actually 'starve' before you pitch. When it's your first time or two, it can be difficult to know how long it's going to take to cool the wort to pitching temp. So here's my unsolicited advice: wait till the wort is cooled, then rehydrate, then pitch. Don't pitch while cooling. Good luck!
     
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  11. jtmartino

    jtmartino Initiate (0) Dec 11, 2010 California

    Understood - so it's less of a viability or quality issue, and more of an economic standpoint. Thanks.
     
  12. billandsuz

    billandsuz Pooh-Bah (2,023) Sep 1, 2004 New York
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    this comes up quite a bit. the answers posted so far are spot on, so i will summarize.

    the factual answer, if not always the practiced method, is that dry yeast should be rehydrated in blood warm water for 5 to 15 minutes before pitching. "proofing" dry yeast will result in a substantially larger colony at pitching. (pitching unhydrated yeast into wort needlessly, sadly and mercilessly kills perhaps 30% upon impact. don't be a yeast killer!)

    a starter is not needed with dry yeast. it is not even required or recommeded. not by brewers or dry yeast producers.

    liquid yeast is more delicate than dry yeast and requires special attention.

    dry yeast has been dried with a full store of oxygen and is "ready to go".

    dry yeast is relatively cheap. if you think you need more, buy another package.

    lastly, it is worth mentioning that dry yeast has a best by date. stale or mistreated yeast is not worth the cost savings.

    so, rehydrate two packages and pitch. sleep well.
    Cheers.
     
  13. mikehartigan

    mikehartigan Maven (1,397) Apr 9, 2007 Illinois

    Dry yeast that has been properly stored and handled can be pitched dry without ill effect. There are those who will disagree with that purely on the premise that rehydrating must be better. People who insist that the result is superior have likely never pitched dry or had another problem that had nothing to do with the dry pitch. I'm not aware of any controlled tests that show a benefit to rehydration. Indeed, there's a link somewhere in which someone did an A-B experiment, and the differences were unremarkable. I'll try to find that link. Estimates of a 50% kill rate may or may not be true, but there's plenty left to do the job just fine. Terms like 'Best Practice' are frequently tossed around, but that doesn't apply here (Best Practice is defined a method or technique that has consistently shown results superior to other methods. That hasn't been done with rehydrated dry yeast). It can be argued that it's a safer bet, to mitigate bad storage practices, but that's typically not an issue. It's 'better' in the same sense that carrying two spare tires in your car's trunk is 'better' than carrying one.
    Pitch it dry. You'll be fine.
     
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  14. Homebrew42

    Homebrew42 Initiate (0) Dec 20, 2006 New York

    It's not an estimate, it's been measured, this is not difficult to do as it only requires very basic lab equipment. During rehydration yeast cells cannot regulate what comes across their membranes, and when rehydrated in wort sugar comes rushing into the cells at toxic levels.
     
  15. mikehartigan

    mikehartigan Maven (1,397) Apr 9, 2007 Illinois

    That's fine, but irrelevant, since, as I said, there's plenty left even after the slaughter. How many spare tires do you carry? ;-)
     
  16. cmmcdonn

    cmmcdonn Initiate (0) Jun 21, 2009 Virginia

    If you make a bigger beer and do this, you may end up underpitching. I believe this makes it relevant.

    I'm sure tossing yeast in dry will work 90% (or more) of the time, but rehydrating is such an easy step, I don't know why anyone would intentionally choose to ignore it.
     
  17. tngolfer

    tngolfer Initiate (0) Feb 16, 2012 Tennessee

    Fermentis recommends both ways to pitch on their website. They do list rehydrating first so I took that as a hint and I rehydrate 90% of the time.

    http://www.fermentis.com/fo/pdf/HB/EN/Safale_US-05_HB.pdf
    Pitching instructions: Re-hydrate the dry yeast into yeast cream in a stirred vessel prior to pitching. Sprinkle the dry
    yeast in 10 times its own weight of sterile water or wort at 27C ± 3C (80F ± 6F). Once the
    expected weight of dry yeast is reconstituted into cream by this method (this takes about 15 to
    30 minutes), maintain a gentle stirring for another 30 minutes. Then pitch the resultant cream
    into the fermentation vessel.
    Alternatively, pitch dry yeast directly in the fermentation vessel providing the temperature of
    the wort is above 20C (68F). Progressively sprinkle the dry yeast into the wort ensuring the
    yeast covers all the surface of wort available in order to avoid clumps. Leave for 30 minutes
    and then mix the wort e.g. using aeration.
     
  18. CCW

    CCW Initiate (0) May 14, 2012 California

    The rehydration process seems fairly simple provided the timing is right, althought I'm not sure if I will rehydrate the first go around. I'm thinking it may be better for me to pitch the yeast dry and figure out the whole cooling time/brewing process a little more so I'll have a better understanding of the timing needed. I'm thinking to compensate for dry pitching cell loss that I'll pitch an additional pack.
     
  19. VikeMan

    VikeMan Grand Pooh-Bah (3,043) Jul 12, 2009 Pennsylvania
    Pooh-Bah Society

    Does anyone have a source for this idea that the yeast will starve after 15 minutes? I would think they will start to slowly die off, just as a liquid yeast population would if you sit it on your counter at the same temperature, or in the fridge (much more slowly). But what's special about dry yeast that they will almost instantly bite the bullet?
     
  20. mikehartigan

    mikehartigan Maven (1,397) Apr 9, 2007 Illinois

    I won't disagree with that. I should have qualified my comments as applying to 'normal' gravity beers. For heavier beers, I either pitch additional packets or, more likely, brew up a five gallon 'starter' and pitch on the cake.
    for me, it's worked 100% of the time I've done it. I rehydrated a few batches years ago and decided it wasn't work the extra hassle, minimal as it is, or the risk. There was a post here a while ago in which it was concluded that rehydrating dry yeast actually creates more problems than it 'solves' (I put 'solves' in quotes, because the problem that it is supposed to address - inferior beer - has not been demonstrated). And I'm a firm believer that, regardless how trivial the effort, not doing it is easier than doing it, particularly if it serves no useful purpose. I don't rehydrate my dry yeast for exactly the same reason I don't twirl three times before getting into my car in the morning.

    That said, even if it brings you nothing more than peace of mind, then, by all means, do it. Placebos can be very effective medicine - if it works, I don't care why.
     
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