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SlickRick07

Rehydrating Dry Yeast

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For new brewers like myself, I am interested in hearing how many homebrewers practice reyhdrating their dry yeast and what technique they use. I know John Palmer basically recommends boiling 1 cup of water, adding it to a sanitized measuring cup, adding a teaspoon of sugar, and then covering it for 30 minutes to see if the yeast is churning. What techniques do you use?

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I did it once, killed the damn yeast, I re-hydrated too hot but the instructions said to do so. I probably was at the upper limit of the suggested re-hydration temp though.

Since then I don't bother, I just throw it in my wort and let it sit for 15 minutes, stir the crap outta it after that.

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I go to the manufacturer's site and see what it says. Most seem to follow what you'll find on the forum by searching - heat 1 cup water to boiling, let cool to mid 90s, pitch yeast and cover 15 minutes, stir, cover 15 minutes more, check temp and pitch when it and wort are within less than 10 degrees. If it's too hot, add a small bit of wort, wait 5, do it again until temp drops. Sugar is not necessary.

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"RickBeer" post=381032 said:

I go to the manufacturer's site and see what it says. Most seem to follow what you'll find on the forum by searching - heat 1 cup water to boiling, let cool to mid 90s, pitch yeast and cover 15 minutes, stir, cover 15 minutes more, check temp and pitch when it and wort are within less than 10 degrees. If it's too hot, add a small bit of wort, wait 5, do it again until temp drops. Sugar is not necessary.

^^This^^

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I practiced rehydration of dry yeast on 8-10 batches. I did not perceive any benefit from doing so, so I no longer rehydrate. I have perceived a benefit from using yeast nutrient as an addition to my all grain beers, so I use the nutrient.

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"Inkleg" post=381037 said:

"RickBeer" post=381032 said:

I go to the manufacturer's site and see what it says. Most seem to follow what you'll find on the forum by searching - heat 1 cup water to boiling, let cool to mid 90s, pitch yeast and cover 15 minutes, stir, cover 15 minutes more, check temp and pitch when it and wort are within less than 10 degrees. If it's too hot, add a small bit of wort, wait 5, do it again until temp drops. Sugar is not necessary.

^^This^^

+1

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I have been re-hydrating dry yeast but do go to the website to see if it is recommended and at what temps first. I am surprised at how high they want the water temp vs the pitching and fermenting temps.

I boil the cup of water (and cover with a piece of sanitized foil) as the first step after I have sanitized everything because it takes so long to cool down, I don't add sugar.

I don't like that the yeast does not evenly re-hydrate and there is always some dry yeast on the surface that I have to try and swirl in right at pitching time; if I try stirring the yeast just sticks to the spoon.

The advantage I see is that the lag time is greatly reduced and the yeast get off to a strong start which will hopefully reduce the chance of an airborne infection.

I add yeast nutrient to the boil and aerate like crazy before pitching and after taking an OG reading.

But it also seems like the temps rise unpredictably with happy yeast so I have had trouble figuring out how many ice packs to add when I first put the LBK in a cooler after pitching.

I have had temp spikes at overnight, two days and four days out on different batches that were all the same 8.5Q LBK size and same yeast.

BEER CANNOT BE TRAINED ;)

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Re-hydration of dry yeast is always a good practice. With a LBK sized batch you most likely will not see a difference with the standard 11.5 gram packet. However as you increase your batch size and/or ABV it does make a difference. Re-hydration of dry yeast increases the viable cell count. If you have the book Yeast check out the section on dry yeast it gives ya all the technical goobley-gook as to why. I do at work with baking so th habit is already there

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I rehydrated the Nottingham dried yeast since they recommend it. I used warm tap water (about 1 cup - I did not measure it precisely). I did not boil the water since I've used tap water and spring water in my brews without boiling all of it without any problems. The only water that I boil is the 4 cups (or a more if I plan to do a hop boil) for the LME.

Edit: I should point out that I do sanitize the measuring cup and small bowl I used to rehydrate before pouring the warm water into them.

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It pays to rehydrate yeast and to make starters whenever pitching liquid yeast, the benefit a vigorous fermentation contributes to your finished beer far out weighs the little time spent in preparation.

As a new brewer it took me quite a while before I was able to understand what was going on inside the LBKs during 'the fermentation'. I see posts here all the time from new and conditioned brewers alike about off flavors in their beer and how or why they have them. So this morning I decided to sit down with my morning coffee, since I couldn't sleep anyway, and try to set the record straight and try to explain the 4 things every brewer should know about yeast.

Here's how I view the relationship between yeast, off flavors and fermentation temperatures throughout the typical beer fermentation. While I'm writing this with brewing an Ale in mind the same principals apply equally to Lager fermentations too.

Phase 1 begins as soon as you pitch your yeast and is referred to as the lag phase, which we brewers want to keep as short as possible. The yeast are using up the sugars and oxygen in the wort to load up their food reserves, they won't ferment anything until they've been well fed. Stressing the yeast out with too high temperatures or too low numbers of viable cells will prolong the lag phase and the fermentation will take longer to complete while increasing the amounts and types of off flavors like diacetyl that may or may not ever condition out.

Phase 2 starts as soon as the lag phase ends because now the yeast have enough energy stored up to start multiplying, this is referred to as the growth phase. This is where you begin to see a bit of foam floating at the surface the wort from the production of Co2 and the pH and oxygen levels of the wort will start dropping. If you've pitched enough healthy yeast at the right temperatures into well aerated wort the lag time should have been 6-12 hours and the yeast are now full of energy and off to a very healthy start.

Phase 3 begins as soon as the growth phase is done and is triggered by a lack of oxygen in the wort, this is known as the fermentation phase. This is the phase where the production of Co2, alcohol and your beer's flavor is at it's peak and the wort temperature rises 3-5F higher than the ambient air outside the fermentor. The yeast will stay in suspension, so they come in contact with as many sugars as possible, over the next 3-7 days before they run out of sugars to eat and flocculate out to the bottom of the fermentor. Higher temperatures during this phase will produce more esters or fruity flavors and aromas, like the banana flavors in a hefeweizen. It's interesting to note that another cause of ester production is wort that hasn't been aerated enough.

Phase 4 is the final phase of the fermentation process and it's referred to as the sedimentation phase where the yeast begin consuming and converting any remaining flavor precursors in the wort like diacetyl that will produce off flavors in your beer. During this phase the yeast cells are preparing themselves to go dormant and storing up energy reserves for their deep sleep, even though this is where most of us flush them down the drain. I'd like to point out that the amount of cleanup work left for the yeast to do is dependent on how well we treated, or mistreated, our yeast during the first 3 fermentation phases.

During the sedimentation phase I raise the temperature of my fermentors 3-5F and hold it there for at least 3 days before bottling or kegging my beer. I do this because the yeast will only convert the flavor precursors it created earlier if it's warmer than it was when they created them. There is a limit to this rule though since the yeast can only do so much cleanup before they go dormant. Once the yeast go dormant any remaining flavor precursors will be left in your beer to produce off flavors.

The moral of this post is to always use fresh healthy yeast in sufficient quantity pitched into well aerated wort at the recommended temperature and you will produce some great tasting beer.

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every yeast is different. i just used a wine yeast on a recently started mead. it said to rehydrate in a certain volume of water that was 104-110F for 15 minutes . stir. pitch.

some dry that ive used for beer the manufacturer says just pitch it into wort.

it pays to read the instructions.

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I use a 8 oz of bottled water. Warm it up to suggested hydration temp if I know it or to around 80F. I pour off about an ounce, pour in the yeast and put the cap back on. Wait 15 minutes and shake it up then wait another five minutes to pitch.
Works for me.

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I usually spray a cup, spoon, scissors and yeast packet with Star San and use warm tap water. I stir the crap out of it then cover it with sanitized aluminum foil for between 15-30 minutes or until it gets a frothy head on it.

I pour some into the fermenter, then stir it a little more to make sure I get all of it out!

No problems so far!

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Last night I made my Carribou Slobber recipe and rehydrated my yeast for the first time. I probably warmed my 1 cup of water too early as the temp by the time I added it to the LBK was in the mid 60's. I cooled the wort though to around the same temp and added them together. I'm not sure if that's a great first set up for rehydrating but I pitched the yeast at midnight last night and it had a strong Krausen by 8:00 AM this morning. I actually believe it did make a difference to rehydrate because that's as quick of a turn around on the Krausen as I've had so far. It seemed like the yeast was pretty prepared by the time it was added to the wort.

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+1 on rehydrating your dry yeast. The percentage of the yeast cells that survive the initial lag phase in a healthy condition to then begin multiplying is much higher than if you just sprinkle dry. This has to do with the walls/membranes of the yeast cells having been weakened during the drying process. Those walls (which control the flow of nutrients in and waste out of the cell) are best rebuilt in warm tap water, not wort.

For a Mr. Beer yeast packet -

1) When you are about to start brewing, put 1/2 cup water (not distilled) in a Pyrex cup in the microwave. Boil it a few minutes, down to about 1/4 cup.

2) Cover the cup with a piece of sanitized foil (sprayed with Star-San if you have some). Set it aside to cool to about 90-100*F.

3) Once the water has cooled, sanitize the yeast packet and cut open with sanitized scissors.

4) Sprinkle it on the water, cover and let sit 15 minutes.

5) Stir, cover, and let sit 5 more minutes.

6) Hopefully by now, you have an LBK full of wort chilled to about 63-65*F and ready for the yeast.

7) The yeast slurry needs to be "attemperated" before you pitch it in the wort. That means you have to add small amounts of the cooler wort into the yeast slurry, stir and let it sit a few minutes. You'll probably have to do this a few times to get it to within 10*F of the wort temperature. Once it's within 10*F, pitch away.

Double the water amount for an 11 gram packet like Nottingham or US-05.

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