### Author Topic: How long will diluted yeast last?  (Read 851 times)

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#### mkevenson

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##### How long will diluted yeast last?
« on: November 24, 2013, 11:54:56 AM »
Recently I was reminded of a method for measuring very small amounts of yeast. The method involves diluting 1g of yeast in 99g of water and then using some of that dilution in the dough. My question is, if one wanted to save the diluted unused solution, how long would it be active, and good to use in future doughs?

Mark
"Gettin' better all the time" Beatles

#### TXCraig1

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##### Re: How long will diluted yeast last?
« Reply #1 on: November 24, 2013, 01:06:21 PM »
Not very long. In any case, what would be the point of saving it?
"We make great pizza, with sourdough when we can, commercial yeast when we must, but always great pizza."
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#### Pete-zza

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##### Re: How long will diluted yeast last?
« Reply #2 on: November 24, 2013, 01:27:52 PM »
Recently I was reminded of a method for measuring very small amounts of yeast. The method involves diluting 1g of yeast in 99g of water and then using some of that dilution in the dough. My question is, if one wanted to save the diluted unused solution, how long would it be active, and good to use in future doughs?
Mark,

Since one gram of yeast (I'm assuming IDY) in 100 grams of water is about 1/3 teaspoon IDY in about 3.5 ounces of water (by weight), why would you want to save the unused IDY/water mixture? And if you decided to save it, where would you store the mixture, and at what temperature?

Under normal circumstances, the instructions for prehydrating dry yeast call for prehydrating the yeast in warm water at around 100-105 degrees F for about 10 minutes. Some time ago, I recall that Tom Lehmann said that one should not let the prehydrated yeast/water mixture sit around too long. I think the maximum he mentioned was around 15 minutes or maybe 20 minutes. Maybe that is a problem when you are using a lot of yeast but your dilution is so great that it is hard to imagine that the yeast would be similarly affected.

Peter

#### mkevenson

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• Age: 65
• Location: Santa Rosa, Ca
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##### Re: How long will diluted yeast last?
« Reply #3 on: November 25, 2013, 11:27:27 AM »
I know it sounds ridiculous!   It is just my Scotch nature, waste not ,want not etc. I guess it comes from an upbringing where my mom counted pennies.

Thanks for the kind comments, I decided to buy another scale. More toys make me happy

Mark
"Gettin' better all the time" Beatles

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