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Rehydrate yeast first, or not?

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ryan850

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I'm new to this.. fermenting my first batch right now (apple cider wine). I had a question about re-hydrating yeast. Does everyone do this? I was told to just sprinkle it on top and not bother with rehydrating. It's fermenting just fine.

What's the advantage of rehydrating first. Also, why the high temperature of 100-105? If it ferments at 65-75, why would it matter so much that you have the 100-105 temperature? and is the advice I heard regarding that temperature good?

What exactly is the disadvantage of going straight to the must first? I have heard that it takes longer for the yeast to begin fermentation, but mine was going strong after about a day. Also, is it a problem if it takes a little longer to start?

Thanks for all the advice.. you guys have helped me out so much!
 

BobF

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I'm new to this.. fermenting my first batch right now (apple cider wine). I had a question about re-hydrating yeast. Does everyone do this? I was told to just sprinkle it on top and not bother with rehydrating. It's fermenting just fine.

What's the advantage of rehydrating first. Also, why the high temperature of 100-105? If it ferments at 65-75, why would it matter so much that you have the 100-105 temperature? and is the advice I heard regarding that temperature good?

What exactly is the disadvantage of going straight to the must first? I have heard that it takes longer for the yeast to begin fermentation, but mine was going strong after about a day. Also, is it a problem if it takes a little longer to start?

Thanks for all the advice.. you guys have helped me out so much!
I always rehydrate at the mfr recommended temp.

I also feed must to develop an active starter.

I do this b/c a) it proves the yeast is viable and b) I want the must vigorously fermenting as quickly as possible.
 

ryan850

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I've heard that rehydrating incorrectly can lead to problems. How much wiggle room is there? What I mean is, how hard is it to screw it up. Say my thermometer is off and it's 95 or 110 degrees, will I kill it?

Do you rehydrate in just plan water with a bit of the must? If so, what's a good ratio?
 
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i think the correct way is to start with sugar water for a period (12 hrs?) and then add some of the must so it acclimates to it. then add must 12 hrs later? that's how i remember it. never did a starter myself. there are wines that i will do so next time on. blueberry and cranberry come to mind that were very slow to ferment for me. IMO, a steady fermentation that's over in ~8-14 days is best. the yeast strain will make a difference also. we've used the lalvin 1116 for the slow fermenters, but it may not be best. we just don't always have the time to make a starter.
 

BobF

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I've heard that rehydrating incorrectly can lead to problems. How much wiggle room is there? What I mean is, how hard is it to screw it up. Say my thermometer is off and it's 95 or 110 degrees, will I kill it?

Do you rehydrate in just plan water with a bit of the must? If so, what's a good ratio?
Most of the yeasts I use say to rehydrate for 15 or 20 minutes in water. The temp ranges are pretty wide - I shoot for the middle of the range, using a candy thermometer to verify.

AFTER rehydrating in plain water for the first 15-20 minutes, I add ~1/2 cup of must - a little bit at a time to make sure I don't temp shock the yeast. 2-4 hours later, I add another 1/2 cup. After another 2-4 hours, I stir well to get everything off the bottom of the jar and pour it into the must. By this time there is lots of foaming going on, the temp is right, and sometimes I can hear rowdy yeast yelling, "Hell, Yeah - Let's make some ALCOHOL!"
 

Luc

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There are so many things that can go wrong by hydrating the yeast it is mostly not recommended.
The water can be too hot and the yeast will boil. You wait to long and the yeast may starve from lack of nutrients. Etc. etc etc.

Learn to make a yeast starter. That way the yeast will really hit the must running. You are also assured that you have a healthy yeast to start with.

You can find how a starter is made here:
http://wijnmaker.blogspot.com/2007/08/gist-starter-yeast-starter.html

Luc
 

Wade E

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I agree with a yeast starter and not rehydrating. Make yourself a yeast starter by using some of the must or just some apple or orange juice with some added sugar and nutrient. Its is best to do this because like Luc says you know its goo yeast and not waiting a few days to find out you need to get back to the store fast toget a new packet and the second reason is you want alcholol being made as fast as you cn to potect your juice from going bad. A juice just sitting in warm temps for long periods of time is prone to spoilage!
 

St Allie

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one point to make on this topic..

some yeasts come in foil packets.. these can be stored at room temp and have an expiry date printed on them..

when I buy yeast in the home brew store ( HBS) they sell them from the refrigerator in plastic bags ( 5 grams). If you buy refrigerated (granulated)yeasts.. get them home quick and back into the fridge.. you can store those six months with good viability. I'm sure they will last even longer, however I haven't tested the theory.

liquid vials have an expiry of 1 to 3 months depending on the yeast strain, they will also be labelled with an expiry date, these must be back in the fridge as soon as possible after purchase, as in such small vials, temp fluctuations can damage the product.

Alllie
 

Wade E

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Evewn the foil packets should be kept refridged for best results.
 

Lizzybob

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I just read an answer for this in a link to some wine kit tips, and will post the link in a new topic as soon as i get 2 more posts :re

They say not to re-hydrate (again, this is specific to kits).
 

Manimal

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I think that as long as you are careful to follow the instructions, it is preferable to rehydrate. The whole point of rehydration is to ensure that you inoculate the must with the optimal number of VIABLE yeast cells. If you don't rehydrate, and just toss them in some must, there will be osmotic stress put on the yeast as they try to take in water in a high sugar environment. So I'd say you should follow the instructions and rehydrate in water at the proper temperature. If you can get a yeast rehydration nutrient like GO-FERM, to add to the rehydration water, that's even better... just make sure it isn't a regular yeast nutrient since the DAP included is toxic to yeast at that concentration.

Sure, you will likely have little trouble with most fermentations just tossing the yeast in, but when you have difficult fermentation conditions such as low temperatures, low nutrient, etc. a properly prepared yeast inoculum can help get you to the end. Google Scott Labs and check out their website for more info on yeast rehyration.
 

Tom

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Either way will work. I like to give the yeast a head start by making a starter or rehydrate the yeast
 

djrockinsteve

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I too use the Lalvin yeast packets. 15 minutes in warm water (@2 ounces) then into my juice. Several hours later I can see some bubbles and the next day it's fully underway. I also use pectin enzyme (20 drops per 6 gallon bucket) with the yeast. I have always had success this way.
 

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