Yeast stopped working. Dough-y no rise-y anymore!

[yelloguy]

I have been using an improvised version of the Papa Gino's recipe posted on this site (thanks Pete-zza) for over a year now. But lately the dough does not rise as much. So yesterday I tried a version of Papa John's clone (thanks again to Pete-zza). And this time there was no rise at all. Even in the oven. First recipe calls for about 2.2 cups of flour and about 0.72 tsp of IDY. I take about 0.75 cups of water and warm it in Microwave for about 50 seconds. I have done it many many times. The second recipe called for about 1/8th tsp IDY in about 2.5 cups of flour. So the percentage was much lower. Which explains the lack of rise.

I use the Yeast bought at BJ's. I think it is IDY but I am not sure if it is ADY. I forget the brand. However, it is not the first time I have tried it. Does it go bad? I have tons of that stuff. Is there a way I can test? Should I increase the percentage of yeast far more than the recipe?

Thanks for any comments. And thanks for all the Pizza!

[The Dough Doctor]

Wow, In our microwave, that much water for 50-seconds at full power the water  will be very hot. The thermal death point for yeast is about 140F, or a little less. It could be that the water was too hot and killed the yeast. For hydrating the yeast (ADY) you want to use 100F water (use a thermometer), if you are rehydrating IDY the correct water temperature is 95F.
Yeast does have a shelf life. If it is unopened, IDY will have about a 1-year shelf life, while ADY will have about a 6-month shelf life. Once opened, you will probably see some loss of yeast activity (but not total loss) after two weeks for either IDY or ADY, and you should try to use it up within 30-days. Yeast is cheap, and it just makes good sense to use fresh yeast whenever possible. By the way, we have kept IDY, in unopened packages, in the freezer for up to two years and only lost about 25% of the yeast activity, not bad, all things considered.
Tom Lehmann/The Dough Doctor

[Pete-zza]

yellowguy,

I heated 3/4 cup of water in normal fashion in my microwave unit for 50 seconds and the temperature was close to 150 degrees F. If you stirred the yeast into the flour before using water at a temperature of around 150 degrees F, the flour might have buffered and protected the yeast somewhat from the overly hot water but if the amount of yeast was low, then it is quite possible that it didn't survive the hot water.   

Peter

[yelloguy]

Thanks for the responses, guys. You are right the yeast is probably a year old and the water temps might be too high. I don't have the food thermometer but now that I think about it, I can use the oral therm'r to experiment first.

I will get some fresh yeast and get the water temperature right this time. I just wish they would sell medium sized packets of IDY. They either sell those tiny pouches at grocery stores or for the same price, they sell bucket-loads at BJs.

[dmcavanagh]

There is absolutely no need to use hot or even warm water to proof yeast, and that applies to active dry yeast or instant yeast. Years ago this may have been the case, but no longer.

[Pete-zza]

There is absolutely no need to use hot or even warm water to proof yeast, and that applies to active dry yeast or instant yeast. Years ago this may have been the case, but no longer.

Dave,

Can you elaborate further on how you came to that conclusion?

Peter

[dmcavanagh]

I make all my doughs with cool and often refridgerator cold water, never have had a dough fail to rise. I learned that the yeasts of today are much more reliable and much more active than the yeast that was available years ago when all the instructions about hydrating yeast with warm water were written. Many good books on bread baking will confirm this. Modern instant yeast was developed to eliminate the proofing step and is widely used by some of the most prominent bakers. All of Peter Reinhart's bread recipes call for instant yeast. Even active dry yeast will perform reliably without warm water. The breads and pizza doughs I make can attest to that.

[scott123]

There is absolutely no need to use hot or even warm water to proof yeast, and that applies to active dry yeast or instant yeast. Years ago this may have been the case, but no longer.

For what it's worth, this has been the case for me as well for both ADY and IDY.  Hitting a particular yeast proofing temp is such a hassle.  I always keep my water at room temp, and, before I make the dough, I'll check the thermostat to see what room temp is and record it. If room temp is extremely high or low, I might tweak my yeast quantity or my fermentation time, but most of the time, room temp is in a pretty narrow window.  I also compensate for older yeast by adding a bit more. I dissolve both ADY and IDY in water prior to adding the flour, because I'm always concerned, with my minimal kneading that I might get a pocket of undissolved yeast, but I always work with room temp water- going back years, and have never had a problem. My ferments are incredibly predictable.

[TXCraig1]

Even active dry yeast will perform reliably without warm water.

I agree, but it still is easier to dissolve ADY in warm water. What is to be gained by not warming the water if only slightly?

CL

[scott123]

I agree, but it still is easier to dissolve ADY in warm water. What is to be gained by not warming the water if only slightly?

CL

Fridge temps are relatively constant, and, for most times of the year, so are room temps.  Warm water from the faucet isn't always going to the be the same temp, not to mention the dangers  of lead leached from warm water pipes.  In order to work with warm water, you have to heat cold water to a specific temp.  If, say, I need 90 deg. water, I nuke it for a bit, measure the temp, nuke it for a bit more, and so on. If I overshoot the mark, I have to give it time to let it cool or add more water and re-measure.  That's a lot more difficult for me than just grabbing a bottle of room temp 73 deg. water.

[Pete-zza]

I can only speak for myself, and others are free to do as they wish, but until the yeast producers like SAF and Fleischmann's come out publicly and say that their ADYs as sold to home bakers are now so good that there is no longer a need to rehydrate them in warm water, and that they will no longer state that advice on their yeast packaging and at their websites, I will not advise anyone--and certainly not any newbie--to stop rehydrating ADY in warm water. We have members who are highly skilled and have found ways to use yeast in various forms and in various ways that may not be conventional, but I would not want to use those experiences as a basis for telling others to ignore the yeast producers' advice on rehydrating ADY with warm water. As far as I know, even modern strains of ADY still have a different geometry than IDY cells and contain more dead cells than IDY that require penetration by warm water to activate the live cells.

I can also understand the usefullness of rehydrating IDY in short mix/knead situations. Tom Lehmann made such a suggestion recently and it is the recommended practice when using VCRs (vertical cutter mixers).

Having read Tom Lehmann's advice on this point to professionals for many years, which advocates rehydrating ADY in warm water, I'd be interested to get his input on this.

Peter

[TXCraig1]

Fridge temps are relatively constant, and, for most times of the year, so are room temps.  Warm water from the faucet isn't always going to the be the same temp, not to mention the dangers  of lead leached from warm water pipes.  In order to work with warm water, you have to heat cold water to a specific temp.  If, say, I need 90 deg. water, I nuke it for a bit, measure the temp, nuke it for a bit more, and so on. If I overshoot the mark, I have to give it time to let it cool or add more water and re-measure.  That's a lot more difficult for me than just grabbing a bottle of room temp 73 deg. water.

I've always dissolved it in a quantity of water small enough to be insignificant to the total formula with the balance of water near 40F. I've never even considered warming all the water.

BTW - worrying about lead leaching from warm water pipes seems strange from a guy who sprinkles bromate on his breakfast cereal...  

CL

[scott123]

Craig, one would think that my concerns about leached lead would only strengthen my bromate arguments because it shows that there are food safety practices that I vigorously adhere to and that my brom-love isn't just an overall sense of laissez faire.  In other words, when something poses an actual risk, I act accordingly

Oh, and everyone knows that MSG is far better on cereal than bromate.  Umami-Os- coming to a supermarket shelf near you.

[dmcavanagh]

I tried to link to a You Tube video of a segment from Master Chef Australia (which I know about from a previous post on pizzamaking) which shows one of the pastry chefs making a focaccia like bread studded with grapes where he is making the dough by hand with cool water. Apparently they had to remove the segment for copyright violations,

[Pete-zza]

I forgot to mention the glutathione problem associated with using cold water with ADY. See the rehydration discussion at http://www.lallemand.com/BakerYeastNA/eng/PDFs/LBU%20PDF%20FILES/1_6DRYYE.PDF.

Peter

[dmcavanagh]

BTW yelloguy, if your BJ's is the same as mine, the yeast you have is probably Fleishmann's instant yeast. My store sells a unit of 2/1lb bags for $4.49. I always have a small working supply in a small glass container in the fridge, and I freeze the rest until I need to refill my working supply. Also, as specified on their own website, rapid rise and bread machine yeast are the same as the instant yeast that BJ's sells. They just package and label the same yeast in different ways. Can't beat the bargin you get by buying that package at BJ's

[yelloguy]

I went to BJ's and bought another pack of Fleischman's IDY. You are right that they are 4.49 for a twin pack of 1 lbs each. That is cheap but wasteful since I cannot use it all within two years' expiration period.

My previous yeast is also the exact same thing and I have one unopened pack going in garbage and the open package is in a glass jar barely used. This time I will keep it in freezer.

Also, I experimented with warming water and I got it to 95 degrees by warming 3/4 cup for 15 seconds. Since there is a raging debate (hehe) between heating and not heating the water, I guess I can just do 10 seconds. I am going to give it a shot tonight. I will know tomorrow if it rises or not.

Thanks so much, everyone.

[dmcavanagh]

yelloguy, just put your extra yeast well packaged into the freezer, it will last well past the stated expiration date if you do so. I'd be willing to bet that the yeast you threw in the trash is probably still good also.

[yelloguy]

The unopened pack is still on the kitchen counter. Expiration June 2011. Tell you what, tonight I am going to open that pack first and use it about 25% more than needed by the recipe. With the 10 seconds warm water, it should work ok. If it does NOT work, my daughter will have her favorite pizza (heh, she said it was the best I *ever* made) tomorrow (without any rise). If it works, I will return the new unopened twin pack for a refund and will be $4.49 richer!

[The Dough Doctor]

Here's my two cents worth.
ADY and IDY, the instant part of IDY is in reference to the rate of hydration for the yeast. IDY hydrates more quickly than ADY, this is why it can be added to the dough without prehydration, this is also why it tends to tolerate cold water hydrating better than ADY. The whole thing about prehydrating yeast is to minimize the flushing effect of cold water entering into the yeast cells and flowing out, bringing with it the plasma material from within the yeast cells (glutathione). When this happens, the yeast cells are not killed, but they don't ferment nearly as well as sound yeast cells do. Also, there is a reducing (softening) effect upon the dough from the glutathione. This may not be seen as readily by home pizza makers as it might be interpreted as just a little too much water, but in a pizzeria or other large production facility it can mean difficult dough handling properties, or even collapse of the dough at some point. Is it absolutely necessary to prehydtrate IDY or ADY in water at specified temperature? In home made pizza dough, the answer is no, will it hurt anything if you do prehydrate it? The answer again is no. So what is the benefit to prehydrating ADY and IDY? The answer is better, overall yeast performance and consistency. How hard is it to get a small amount of water at 95F for IDY or 100F for ADY? Not hard at all. Just remember that both of these temperatures are at near skin/body temperature, it only takes a minute, actually, just a few seconds.
Tom Lehmann/The Dough Doctor