Starter with dry yeast

[JPrather]

Okay, so I bought Yeast: The Practical Guide to Beer Fermentation and this is what they had to say about on this subject:

"Another case where you normally do not want to make a starter is with dry yeast. Dry yeast is inexpensive, and it is usually cheaper, easier, and safer to buy more dry yeast than to make a large starter. Many experts suggest that placing dry yeast in a starter just depletes the cell reserves that the yeast manufacturer tries to build into their product. For dry yeast do a proper rehydration in tap water; do not make a starter."

Notice that their advice is that you normally don't want to do a starter with dry yeast (not never). They then go on to give the reasons why, which are:
-cost
-ease
-safety (I'm assuming they mean less chance of contamination?)
They then also recommend against pitching dry yeast directly on the wort, which we already know to be the case.

So, after reading what these two guys wrote, I'm still not seeing how making a starter out of dry yeast is detrimental to the beer if more yeast than what are in a dry pack are needed for the fermentation. Sure, it may be easier, cheaper, and safer... But we're talking about making great beer here, not pinching pennies, right? And most here should be able to maintain sanitary conditions. And your explanation still doesn't make sense to me the way in which you explained it.

I'm a firm believer in facts and science. I have a bachelors of science degree in biology. Although I may not be an expert in zymology, I do have a solid science background. Just because an expert says something, doesn't mean it's a "fact." From what I've read on this, it appears this is a good example. The authors recommend against making a starter out of dry yeast, but their reasons for recommending against it don't appear to be motivated by the quality of the final product, but more so by the extra work and cost to get there.

Just quoting this for kombat's sake because he apparently missed it the first time.

 

[max384]

Can you blame me? He said "I might be the first with enough sac to say I did it and I liked the results." Come on, who says s**t like that? Like he's some kind of courageous pioneer and everyone else in the past 4,000 years of brewing history has been too cowardly to admit they went against expert advice and liked the results. Gimmie a friggin' break. The attitude, geez.

I laughed when he said that too. That was a bit over the top. But, he wasn't the first in this thread to start with the attitude.

 

[max384]

Marginally. By about 30%, according to the charts in the book "Yeast."

So if he properly rehydrated a packet of yeast containing 200 billion cells and grew it in a 1L starter, he'd end up with 260 billion cells.



No. A second hydrated pack would be another 200 billion cells, making his total 400 billion, which is substantially more than the 260 billion he got by making a pointless starter.

This is also straight from the "Yeast" book:

"The starter's purpose is to create enough clean, healthy yeast to ferment your batch under optimal conditions. The primary focus of a starter should always be yeast health first and increased cell growth second. Many brewers mistakenly focus on cell growth at the expense of yeast health."

Later he says:

"Starters rarely have a negative side; even if there is little yeast growth, a starter helps to revive yeast for fermentation by activating metabolism, and therefore fermentation starts faster."

I think your focus here is misplaced.

Yes, they are. As already quoted, White/Zainasheff advise against making starters with dry yeasts. It's already been quoted in this very thread. They say, "Many experts suggest that placing dry yeast in a starter just depletes the cell reserves that the yeast manufacturer tries to build into their product. For dry yeast do a proper rehydration in tap water; do not make a starter."

So if the OP made a starter, then yes, it is indeed directly against the advice of the experts who wrote the book on the subject, own professional breweries, and have brewed thousands and thousands of gallons of beer on a commercial scale. But somehow, you don't think that's a "misstep?"



No, as I just said, the experts advise against it.

Why is this so hard? It's right there in black and white!

You completely ignored the first part of his paragraph where he recommends against using a dry yeast starter, where he gives the reasons why he doesn't recommend making one, which have nothing to do with quality of the beer. Also, the last part of the paragraph that you just quoted, was talking about pitching dry yeast directly into wort, which I think everyone here is in agreement is not the best practice.

And just think if nobody ever challenged the status quo. Where would we be right now?

 

[kombat]

Just quoting this for kombat's sake because he apparently missed it the first time.

No, I saw it. But why does everyone keep missing the part of the quote where they say, "Many experts suggest that placing dry yeast in a starter just depletes the cell reserves that the yeast manufacturer tries to build into their product."?

 

[JustLooking]

You completely ignored the first part of his paragraph where he recommends against using a dry yeast starter, where he gives the reasons why he doesn't recommend making one, which have nothing to do with quality of the beer.

My interpretation would be that the other monetary reasons are only mentioned as a side note to appeal to our sense of frugality. That the important thing to take away is that you're decreasing your yeasts ability to emerge from rehydration vital and ready to reproduce. Your quote, "Starters rarely have a negative side," is only true of liquid yeast and has no bearing here. By making a starter with dry yeast you may increase the count, but you take away from its ability to reproduce quickly and cleanly.


Oh, and pitching 3 quarts of starter wort into beer sounds yummy :cross:

 

[max384]

No, I saw it. But why does everyone keep missing the part of the quote where they say, "Many experts suggest that placing dry yeast in a starter just depletes the cell reserves that the yeast manufacturer tries to build into their product."?

Because he then says to rehydrate it. I read this as him recommending against adding dry yeast directly to the starter wort, as he then says to make a proper starter.

And who are these "many experts," and where is their research to back up this claim? Any time that anyone cites "many experts" as their source, you should be very dubious of their claims. I looked through his sources at the end of the book, and I didn't see anything that looked to be the source of that claim.

My interpretation would be that the other monetary reasons are only mentioned as a side note to appeal to our sense of frugality. That the important thing to take away is that you're decreasing your yeasts ability to emerge from rehydration vital and ready to reproduce. Your quote, "Starters rarely have a negative side," is only true of liquid yeast and has no bearing here. By making a starter with dry yeast you may increase the count, but you take away from its ability to reproduce quickly and cleanly.


Oh, and pitching 3 quarts of starter wort into beer sounds yummy :cross:

It would be very strange for an author to give three reasons not to do this as only a side note to start out his paragraph.





Could somebody please explain how making a starter could deplete the yeast's cell reserves? A starter is basically just a small batch of wort. If putting rehydrated yeast into a starter wort depletes the yeast's cell reserves, how is it any different if pitching into the actual wort. I'm just not understanding the fundamental reason behind this.

 

[Terek]

I do a starter always with dry yeast. I don't care what is said or written, I see time and time again it being beneficial. Also, I see a lot of things saying to just pitch another packet. If I only need 230 billion cells, why would I want to pitch 400 billion? That is way over pitching and will Definetally change the flavor profile. I have found that what works best, is to do a starter right before bed, then brew in the morning. Around 8 hrs on the stir plate seems to work perfect. Less time, and you might as well just re hydrate. More time, and it does tend to "tire" out the yeast. With this, it basically lets them wake up and get ready for the work ahead.

I mainly use dry yeast. I have tried strait pitching, rehydrating, short starter, medium starter, and long starters. Time and time again it's the 8 hr starter I get the best results. Period. Anyone can write a book, or post info on the internet, but i will do what works best, period. I see it with my own eyes time after time.

 

[boydster]

Could somebody please explain how making a starter could deplete the yeast's cell reserves? A starter is basically just a small batch of wort. If putting rehydrated yeast into a starter wort depletes the yeast's cell reserves, how is it any different if pitching into the actual wort. I'm just not understanding the fundamental reason behind this.

This is from Clayton Cone. Hopefully he's a source that will command a little bit of respect.

We recommend that the rehydrated yeast be added to the wort within 30
minutes. We have built into each cell a large amount of glycogen and
trehalose that give the yeast a burst of energy to kick off the growth
cycle when it is in the wort. It is quickly used up if the yeast is
rehydrated for more than 30 minutes. There is no damage done here if it is
not immediatly add to the wort. You just do not get the added benefit of
that sudden burst of energy.

See the full text here.

If you are adding the dry yeast to a starter that isn't sufficiently large to allow most or all of the cells to go through at least one division, then you are effectively wasting that energy boost that Clayton Cone and others in this thread have been talking about.

 

[cjgenever]

Can you blame me? He said "I might be the first with enough sac to say I did it and I liked the results." Come on, who says s**t like that? Like he's some kind of courageous pioneer and everyone else in the past 4,000 years of brewing history has been too cowardly to admit they went against expert advice and liked the results. Gimmie a friggin' break. The attitude, geez.

Haha.I was being silly. I have a thing called a sense of humor. My head isn't that big

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[boydster]

I do a starter always with dry yeast. I don't care what is said or written, I see time and time again it being beneficial. Also, I see a lot of things saying to just pitch another packet. If I only need 230 billion cells, why would I want to pitch 400 billion? That is way over pitching and will Definetally change the flavor profile. I have found that what works best, is to do a starter right before bed, then brew in the morning. Around 8 hrs on the stir plate seems to work perfect. Less time, and you might as well just re hydrate. More time, and it does tend to "tire" out the yeast. With this, it basically lets them wake up and get ready for the work ahead.

I mainly use dry yeast. I have tried strait pitching, rehydrating, short starter, medium starter, and long starters. Time and time again it's the 8 hr starter I get the best results. Period. Anyone can write a book, or post info on the internet, but i will do what works best, period. I see it with my own eyes time after time.

If you only need 230 billion, then pitching 200-220 billion cells is perfectly fine. You're close enough. 25% on either side of the target pitch rate is the window you should be shooting for, you don't need to obsess about getting exactly the right number of cells (how can you even know exactly how many cells you have without having the equipment to do a cell count?).

 

[cjgenever]

Because he then says to rehydrate it. I read this as him recommending against adding dry yeast directly to the starter wort, as he then says to make a proper starter.

And who are these "many experts," and where is their research to back up this claim? Any time that anyone cites "many experts" as their source, you should be very dubious of their claims. I looked through his sources at the end of the book, and I didn't see anything that looked to be the source of that claim.



It would be very strange for an author to give three reasons not to do this as only a side note to start out his paragraph.





Could somebody please explain how making a starter could deplete the yeast's cell reserves? A starter is basically just a small batch of wort. If putting rehydrated yeast into a starter wort depletes the yeast's cell reserves, how is it any different if pitching into the actual wort. I'm just not understanding the fundamental reason behind this.

A starter the way I did it would deplete the reserves because I pitched at high Krausen, after propagation. I pitched enough to not worry about that. I used the hybrid option in Mr malty.

If a starter is provided plenty of nutrient and o2 and left warm after complete ferment, the yeast will build up their reserves.THEN you could crash it. It is a natural part of yeast biology that we can control at home. It is not some magic that is only possible in a commercial yeast lab. So in conclusion, yes, a yeast cells' reserves are used up by making a starter. But if they have proper nutrition they can make more.

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[max384]

This is from Clayton Cone. Hopefully he's a source that will command a little bit of respect.



See the full text here.

If you are adding the dry yeast to a starter that isn't sufficiently large to allow most or all of the cells to go through at least one division, then you are effectively wasting that energy boost that Clayton Cone and others in this thread have been talking about.

I'm sorry, but what you're saying just doesn't make sense biologically the way in which you have explained it. Firstly, he was talking about rehydration, not making a starter. Secondly, he said that there was only about 30 minutes of energy reserve in the dry yeast. In best case conditions, brewers yeast replicates in over an hour and a half. So, I'm having a hard time making the jump from needing at least one cell division or the energy boost is wasted. And where did you get the figure of needing at least one cell division in order for that energy not to be wasted? That figure seems rather arbitrary given the current discussion.

I'm not saying that I'm definitely right on this, but I haven't heard an adequate explanation that answers the WHY we shouldn't do this (other than cost, ease, etc.).

 

[cjgenever]

My interpretation would be that the other monetary reasons are only mentioned as a side note to appeal to our sense of frugality. That the important thing to take away is that you're decreasing your yeasts ability to emerge from rehydration vital and ready to reproduce. Your quote, "Starters rarely have a negative side," is only true of liquid yeast and has no bearing here. By making a starter with dry yeast you may increase the count, but you take away from its ability to reproduce quickly and cleanly.


Oh, and pitching 3 quarts of starter wort into beer sounds yummy :cross:

Isn't the purpose of a starter to let the yeast reproduce? that's why I pitched it at high Krausen, to let it continue as it already was doing. Otherwise it would take a week to rebuild reserves and crash it. It is a little stressful on the yeast to double the sugar concentration all at once, so I did "temper" the starter up to 1055 for an hour before pitching. I doubt that was any huge help, but it didn't hurt anything.

I already said that I used fermentation temps low enough to create decent beer. I tasted it before pitching it and it was fine.if it wasn't I would have crashed it and Decanted. I also mentioned that I adjusted my hopping accordingly. This was actually something that I started doing occasionally based on either Palmer's or Zainasheffs recommendation in the case that you did not want to waste of the DME. I don't know what episode, probably yeast starters. So yes, YUM!

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[max384]

A starter the way I did it would deplete the reserves because I pitched at high Krausen, after propagation. I pitched enough to not worry about that. I used the hybrid option in Mr malty.

If a starter is provided plenty of nutrient and o2 and left warm after complete ferment, the yeast will build up their reserves.THEN you could crash it. It is a natural part of yeast biology that we can control at home. It is not some magic that is only possible in a commercial yeast lab. So in conclusion, yes, a yeast cells' reserves are used up by making a starter. But if they have proper nutrition they can make more.

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I get that their nutrients can be used up. I mean, of course they can. My question is how is this detrimental if they then have proper nutrition and growing conditions in the starter? The nutrients are also used up when they are pitched into wort.




Or another way to look at it is: What is different between properly rehydrated dry yeast and liquid yeast when making a starter (assuming more cells are needed for a particular batch)? Other than the additional nutrients, which can only help the dry yeast.

 

[boydster]

The energy boost is to kick the yeast into reproductive phase. If they aren't reproducing, the boost is wasted.

The OP seems to have made a large enough starter to not put the yeast at a disadvantage, so that's great, but generally people don't make 3 quart starters so that is important information to be given up front to help prevent the typical new brewer from reading this and thinking they should make a 1L simple starter with dry yeast. Context is everything.

 

[cjgenever]

You have quoted no facts supporting your position and it goes against most current studies.

I agree to disagree with you.

The "fact" is that I had a successful and clean ferment. It doesn't get any more real world factual than that.

Btw, you agree to disagree with me is a very nice way to say it. Thanks for being civil!

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[cjgenever]

This is from Clayton Cone. Hopefully he's a source that will command a little bit of respect.



See the full text here.

If you are adding the dry yeast to a starter that isn't sufficiently large to allow most or all of the cells to go through at least one division, then you are effectively wasting that energy boost that Clayton Cone and others in this thread have been talking about.

YES! THANK YOU! I started with an assumed 200 billion cells. I ended with MORE THAN TWICE THAT. This is based on the research of the pros that everyone keeps throwing in my face.

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[kombat]

Haha.I was being silly. I have a thing called a sense of humor. My head isn't that big

OK well that's a little reassuring. Sarcasm and satire are tougher to pick up in a text-based medium like these forums.

 

[cjgenever]

No, I saw it. But why does everyone keep missing the part of the quote where they say, "Many experts suggest that placing dry yeast in a starter just depletes the cell reserves that the yeast manufacturer tries to build into their product."?

Right, but it's not depleting the reserves in a wasteful manner if they go through a full cell division and are not crashed. Then pitched before the starter is fully fermented as to avoid cells from feeding on the reserves.

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[kombat]

The "fact" is that I had a successful and clean ferment. It doesn't get any more real world factual than that.

Except for, you know, actually measuring things like cell viability ratio, starting and ending cell counts, attenuation compared against a control, ester, phenol, and fusel production, affects on flocculation, suitability for re-pitching, generational cell health, and other "sciency" stuff.

 

[boydster]

YES! THANK YOU! I started with an assumed 200 billion cells. I ended with MORE THAN TWICE THAT. This is based on the research of the pros that everyone keeps throwing in my face.

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Like I said, context is everything. You started a thread that you even stated you thought was going to be controversial and you only provided a limited amount of information. If you just provided the details of your experiment up front, a lot of the banter probably would never have happened. Fact is, it is still going to be less expensive to just buy a second packet of yeast than it is to make starter wort to grow more yeast (cost of DME, energy to heat it, etc) if you just plan ahead when you are buying the rest of your ingredients, plus the extra packet of yeast will mean you still get the benefit of the boost of energy - thus, it seems like a better option all around. Of course, if you didn't plan ahead and get the second packet of yeast or for whatever reason you find yourself coming up very short on cell count, obviously making a sufficiently large starter to allow for healthy cell growth isn't the end of the world and can make decent beer.

Think of it this way. If someone posted a thread today that said "I pitched a single vial of WL yeast into my 5 gallon beer and it turned out great!" they would probably be met with some opposition. If after 20 posts they finally say "Well, the beer I made was a 1.025 OG table beer," suddenly it is easy to see why they had good results and the information would have been useful from the beginning to help readers understand that the OP isn't suggesting that his findings are to be applied across the board.

 

[JustLooking]

While on the topic of things omitted, how long did this intermittent shaken starter ferment before being pitched. From the OP it looks like you discovered your lack of sufficient yeast on your brew day.

 

[Terek]

Like I said, context is everything. You started a thread that you even stated you thought was going to be controversial and you only provided a limited amount of information. If you just provided the details of your experiment up front, a lot of the banter probably would never have happened. Fact is, it is still going to be less expensive to just buy a second packet of yeast than it is to make starter wort to grow more yeast (cost of DME, energy to heat it, etc) if you just plan ahead when you are buying the rest of your ingredients, plus the extra packet of yeast will mean you still get the benefit of the boost of energy - thus, it seems like a better option all around. Of course, if you didn't plan ahead and get the second packet of yeast or for whatever reason you find yourself coming up very short on cell count, obviously making a sufficiently large starter to allow for healthy cell growth isn't the end of the world and can make decent beer.

Think of it this way. If someone posted a thread today that said "I pitched a single vial of WL yeast into my 5 gallon beer and it turned out great!" they would probably be met with some opposition. If after 20 posts they finally say "Well, the beer I made was a 1.025 OG table beer," suddenly it is easy to see why they had good results and the information would have been useful from the beginning to help readers understand that the OP isn't suggesting that his findings are to be applied across the board.

I run an extra gallon of sparge water threw my grains before tossing them. Then I take that gallon, boil down to around 2L and save it for next starter. Costs nothing

 

[JustLooking]

I run an extra gallon of sparge water threw my grains before tossing them. Then I take that gallon, boil down to around 2L and save it for next starter. Costs nothing

Where I live we pay for fuel. :cross:

 

[boydster]

Hope you've got that starter on a stirplate, Terek. Otherwise it's a yield rate of something like 0.5 - so only half of those cells are actually dividing (again, just going by the chart in Yeast).

 

[max384]

Like I said, context is everything. You started a thread that you even stated you thought was going to be controversial and you only provided a limited amount of information. If you just provided the details of your experiment up front, a lot of the banter probably would never have happened. Fact is, it is still going to be less expensive to just buy a second packet of yeast than it is to make starter wort to grow more yeast (cost of DME, energy to heat it, etc) if you just plan ahead when you are buying the rest of your ingredients, plus the extra packet of yeast will mean you still get the benefit of the boost of energy - thus, it seems like a better option all around. Of course, if you didn't plan ahead and get the second packet of yeast or for whatever reason you find yourself coming up very short on cell count, obviously making a sufficiently large starter to allow for healthy cell growth isn't the end of the world and can make decent beer.

Think of it this way. If someone posted a thread today that said "I pitched a single vial of WL yeast into my 5 gallon beer and it turned out great!" they would probably be met with some opposition. If after 20 posts they finally say "Well, the beer I made was a 1.025 OG table beer," suddenly it is easy to see why they had good results and the information would have been useful from the beginning to help readers understand that the OP isn't suggesting that his findings are to be applied across the board.

But if a starter is made under ideal circumstances (for the sake of argument), wouldn't this be a healthier yeast to pitch than rehydrated dry yeast? That may be worth the extra time and cost, since it seems like most everyone is in agreement that this doesn't make sense from a time or cost perspective.

 

[boydster]

You are not considering the fact that the yeast was packaged with additional nutrients to help kick it into the growth phase, though. If the options are pitching x amount of cells from a starter versus pitching the same number of cells within 30 minutes of rehydrating, I will take the latter because of the extra nutrient boost.

 

[myelo]

We can discuss theory, anecdotal evidence and authoritative recommendations all day … but what we really need are actual data.

That is, I would be interested in the results of a controlled experiment comparing properly rehydrated dried yeast pitched into the wort and properly rehydrated dried yeast pitched in a starter first.

And after about an hour of searching some databases of scientific publications I can't find any actual studies. There are several published studies on rehydration vs. no rehydration and the type of rehydration (temperature, time and wort vs. water) but nothing I can find on starter vs. no starter for dried yeast. Surely the dried yeast manufacturers or somebody else would have published some actual data on this.

Anybody know?

 

[cjgenever]

Except for, you know, actually measuring things like cell viability ratio, starting and ending cell counts, attenuation compared against a control, ester, phenol, and fusel production, affects on flocculation, suitability for re-pitching, generational cell health, and other "sciency" stuff.

There is no evidence that viability is decreased from the research I've done. I can't test that without a good microscope. The same with cell counts, but a yeast cell with good reserves placed into a large enough starter for the starting cell count is sure to increase numbers of healthy yeast (based on what we've learned from white and Zainasheff, I think they're pretty sciency).

A fast ferment attenuated from 1075 to 1010 AA. MY batch attenuated to 1010 as well. That provides a control to compare the ferment to.

I can't test compound levels, but I do have a very good palate for food, wine, and beer. I can tell you the this fermented as clean as an equivalent put of rehydrated
Flocculation was typical of us-05. I have used this strain extensively.

I have since repitched the slurry (amount determined by Mr malty, based on my need for low esters). I saw the typical results of stronger fermentation with the second pitch.

Nothing much is different other than the initial ferment (first batch) took off more like a pitch from fresh slurry. It seemed like a possibly cleaner ferment, but that could be chalked up to placebo effect since I only have my palate to test.

Generational cell health seems good as there is no evidence thus far of petite mutants, etc. This of course is based on me using my palate to look for the compounds created in excess by such cells, which is somewhat useless at this point. It would be many more generations before numbers of such cells increased to such a point. I really need a lab microscope to Cheech at this point.

I have followed the scientific method add well as I can with my limited resources. I have used what controls I could and notated my observations every step of the way. When I'm back to work I will purchase a decent lab microscope and counting plates to appease you all. I will run some actual controlled experiment and have some concrete facts for you all by the end of this year.I'm not some wily nilly idiot here people

Thanks everyone who has participated civaly!

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[cjgenever]

You are not considering the fact that the yeast was packaged with additional nutrients to help kick it into the growth phase, though. If the options are pitching x amount of cells from a starter versus pitching the same number of cells within 30 minutes of rehydrating, I will take the latter because of the extra nutrient boost.

I have already said just that. The situation didn't really warrant that so I improvised. Only after getting great results did I start this thread. I'm not advocating for starters with dry yeast. I'm only saying that it is possible to make great beer by doing so. I am not saying it is necessary.

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[max384]

You are not considering the fact that the yeast was packaged with additional nutrients to help kick it into the growth phase, though. If the options are pitching x amount of cells from a starter versus pitching the same number of cells within 30 minutes of rehydrating, I will take the latter because of the extra nutrient boost.

I'm considering this. I guess I just have a hard time accepting that rehydrated dry yeast is superior to a yeast starter.

 

[cjgenever]

I'm sorry, but what you're saying just doesn't make sense biologically the way in which you have explained it. Firstly, he was talking about rehydration, not making a starter. Secondly, he said that there was only about 30 minutes of energy reserve in the dry yeast. In best case conditions, brewers yeast replicates in over an hour and a half. So, I'm having a hard time making the jump from needing at least one cell division or the energy boost is wasted. And where did you get the figure of needing at least one cell division in order for that energy not to be wasted? That figure seems rather arbitrary given the current discussion.

I'm not saying that I'm definitely right on this, but I haven't heard an adequate explanation that answers the WHY we shouldn't do this (other than cost, ease, etc.).

Thanks for your support, but I'd like to clarify.

The energy reserves are mostly stored in the cell dro long as there is food in the surrounding environment. These reserves are used primarily to build strong cell walls. The reserves are split evenly between mother and daughter cell during budding. If a cell is put into an aerobic environment without a food source it will use its reserves to survive rather than reproduce.This is why we rinse or yeast with boiled water (other than sanitized), to remove oxygen.

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[boydster]

We can discuss theory, anecdotal evidence and authoritative recommendations all day … but what we really need are actual data.

That is, I would be interested in the results of a controlled experiment comparing properly rehydrated dried yeast pitched into the wort and properly rehydrated dried yeast pitched in a starter first.

And after about an hour of searching some databases of scientific publications I can't find any actual studies. There are several published studies on rehydration vs. no rehydration and the type of rehydration (temperature, time and wort vs. water) but nothing I can find on starter vs. no starter for dried yeast. Surely the dried yeast manufacturers or somebody else would have published some actual data on this.

Anybody know?

What I posted regarding glycogen and trehalose reserves is not anecdotal or theory. Those are built into the dry yeast packets for a specific reason, as has already been discussed. If the yeast uses those resources in the starter before it makes it to the fermentor, there is no difference between that yeast and pitching an identical amount of liquid yeast from a starter. Hence why I said I would take the dry yeast if given the choice between that and an equal number of cells coming straight from a starter.

While I don't have a link to a study like you are asking for, one additional thing to consider is how an authoritative recommendation might come to be.

Here's an interesting read, though: http://www.bioaliment.ugal.ro/revista/2/Paper1pfit.pdf

From page 6, item #4:

4. Trehalose accumulation in the yeast cell
The amount of trehalose in Sacch. cerevisiae can
constitute up to 23% or more of the dry weight of
the cell, depending on the growth conditions and
stage of life cycle (Kim et al., 1996)
Low trehalose concentration in yeast during
exponential phase is the result of glucose repression
(Boulton and Quain, 2001).
It was demonstrated that trehalose concentration
accumulated within the yeast cell is proportional to
the gravity of the wort. Thus trehalose content of the
yeast harvested from an 11°Plato wort accounted for
no more than 2-3% of the yeast dry weight, whereas
this increased to 20-25% of the cell dry weight in
yeast removed from 25°Plato (Boulton and Quain,
2001).
Trehalose starts to accumulate during the transition
from the exponential phase to the stationary phase,
when the glycogen reserves are being utilised. The
repressive effects of glucose are quantitatively
higher in the trehalose synthesis pathway than in
glycogen synthesis pathway. Trehalose accumulates
only after glycogen was produced, the latter one
being used as glucose residue supplier for trehalose
synthesis (Steward and Russell, 1993).

From that, we can infer that yeast coming out of a starter (which would be less than 10°P) will have far less trehalose built into the cell.

The paper goes on to discuss how trehalose is associated with high stress tolerance, which we want when we are pitching yeast into a brand new environment that will have a much higher sugar density than its prior environment whether it was hydrated in water or tossed into a starter wort.

And before we discuss that the yeast can just synthesize its own trehalose (also discussed in that same paper, page 7), its worth noting that it takes energy to do this, whereas the packets come with the reserve already built in and so no metabolic energy needs to be expended to build up additional trehalose.

Given that I know I'm going to be stressing the yeast when it goes into the fermentor due to the large amount of sugars and the upcoming baby boom in the yeast population, I'd much rather go in with yeast that already has the reserves it needs than go in with yeast that will need to replenish those reserves. That said, if I knew the only way I could brew on the day that I had available was to make a starter with a packet of dry yeast, I would make the starter knowing that it won't be the end of the world. Just because something isn't ideal, that doesn't mean it won't work. I just feel like we should stick with best practices whenever the opportunity is there, and leave the improvising for times when you need to get the job done and you're past the point of being able to implement a known best practice.

 

[boydster]

I have already said just that. The situation didn't really warrant that so I improvised. Only after getting great results did I start this thread. I'm not advocating for starters with dry yeast. I'm only saying that it is possible to make great beer by doing so. I am not saying it is necessary.

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That comment was directed at Max384, not you, sorry for the confusion. I was responding to his post immediately before that.

 

[cjgenever]

I run an extra gallon of sparge water threw my grains before tossing them. Then I take that gallon, boil down to around 2L and save it for next starter. Costs nothing

As do I. I add buffering minerals to lower the ph when I do. Probably a waste, but it makes me feel good

 

[myelo]

Boydster, thanks for the link.

While I don't have a link to a study like you are asking for, one additional thing to consider is how an authoritative recommendation might come to be.

That's a great point. Ideally, an authoritative recommendation would be based on data. And if that's the case here, I would like to see the data.

I'm not disputing the recommendations made by folks who know way more about this than I do. I am just interested in knowing what the actual affects are. It's curiosity more than anything.

 

[JPrather]

No, I saw it. But why does everyone keep missing the part of the quote where they say, "Many experts suggest that placing dry yeast in a starter just depletes the cell reserves that the yeast manufacturer tries to build into their product."?

You saw it, and then promptly ignored it in favor of replying to posts that don't annihilate your entire argument.

It's simple, really, and max outlined it in that post. The yeast book recommends against starters because it serves little to no benefit when you have enough dry yeast to pitch. It doesn't say "a starter is never a good idea under any circumstances".

Therefore, making a starter may be a good idea given certain circumstances, without violating whatever "facts" or "science" that have been cited in this thread.

You're making a logical leap that doesn't exist, and that part of the conversation should have ended there.

 

[cjgenever]

What I posted regarding glycogen and trehalose reserves is not anecdotal or theory. Those are built into the dry yeast packets for a specific reason, as has already been discussed. If the yeast uses those resources in the starter before it makes it to the fermentor, there is no difference between that yeast and pitching an identical amount of liquid yeast from a starter. Hence why I said I would take the dry yeast if given the choice between that and an equal number of cells coming straight from a starter.

While I don't have a link to a study like you are asking for, one additional thing to consider is how an authoritative recommendation might come to be.

Here's an interesting read, though: http://www.bioaliment.ugal.ro/revista/2/Paper1pfit.pdf

From page 6, item #4:



From that, we can infer that yeast coming out of a starter (which would be less than 10°P) will have far less trehalose built into the cell.

The paper goes on to discuss how trehalose is associated with high stress tolerance, which we want when we are pitching yeast into a brand new environment that will have a much higher sugar density than its prior environment whether it was hydrated in water or tossed into a starter wort.

And before we discuss that the yeast can just synthesize its own trehalose (also discussed in that same paper, page 7), its worth noting that it takes energy to do this, whereas the packets come with the reserve already built in and so no metabolic energy needs to be expended to build up additional trehalose.

Given that I know I'm going to be stressing the yeast when it goes into the fermentor due to the large amount of sugars and the upcoming baby boom in the yeast population, I'd much rather go in with yeast that already has the reserves it needs than go in with yeast that will need to replenish those reserves. That said, if I knew the only way I could brew on the day that I had available was to make a starter with a packet of dry yeast, I would make the starter knowing that it won't be the end of the world. Just because something isn't ideal, that doesn't mean it won't work. I just feel like we should stick with best practices whenever the opportunity is there, and leave the improvising for times when you need to get the job done and you're past the point of being able to implement a known best practice.

Great info. Thanks!

Sent from my SCH-R970 using Home Brew mobile app

 

[fuelish]

Settle down, children....christ, and I thought the mead makers were anal.....easy answer- it's YOUR beer, do what YOU want with it. Unless you're a professional, it's of miniscule importance - making great beer is easy. Everyobody step back, take a breath, and give it a rest.

 

[max384]

Thanks mom.