Pizza Making Forum

Pizza Making => Starters/Sponges => Topic started by: JD on February 03, 2013, 10:42:33 PM

Title: Cold fermenting in refridgerator with sourdough
Post by: JD on February 03, 2013, 10:42:33 PM
Since TXCraig posted his Sourdough starter quantity predictive model http://www.pizzamaking.com/forum/index.php/topic,22649.0.html (http://www.pizzamaking.com/forum/index.php/topic,22649.0.html) I've been experimenting with cold fermentation in the fridge (35-40*F)

The purpose of these experiments was to test my assumption I could make a naturally leavened dough (no IDY/ADY/Cake Yeast) on any given night, and use it at my leisure during the week without the risk of over or under-fermenting the final dough. The quick summary is that I believe no fermentation occurs at fridge temps (under 40*F) The following is my initial findings:


*All dough made using 8.5% starter, 60% hydration, 550* NY Style*

Experiment #1 (control): 65* warm ferment only for 24 hours (no cold ferment). Great spring, mild flavor & color (due to lack of LAB effect)

Experiment #2: 84 hours cold ferment (fridge), then pull for 12.5 hours at 65* to verify predictive model. Dough seemed highly under-fermented. Poor spring, poor color. This was the initial experiment that started to raise my suspicions on whether a dough made with a starter did any fermentation in the fridge.

Experiment #3: 14 day cold ferment (fridge), 65* warm ferment for 24 hours. Although it would be a good assumption to say this dough would be way over-fermented, turns out that was not the case at all. This dough didn't start showing small bubbles until a minimum of 12 hours of 65* temps, and seemed about right around 24 hours. The spring and color were great. The only negative to this dough was the extreme extensiblility which was a catalyst for weak spots & holes. Other that that issue, the dough was perfect and this was the first time my suspensions were "verified" that little to no fermentation occurs at fridge temps.

Experiment #4: 5 day cold ferment (fridge), 65* warm ferment for 24 hours. This was a good middle of the road experiment to test between my control and my 14 day ferment. Although the dough seemed to be fully fermented, spring & color were very poor. I'm now beginning to suspect that the fridge actually damages the yeast in some way.  
Experiment #4 was thrown away due to learning I stored dough in sub-freezing temperatures during this "cold ferment"

Experiment #5 (TBD). I will take a complete guess and assume 50% of yeast are "harmed" when put into the fridge. I have no reasoning for this number, just a guess. Therefore, I will raise my original 8.5% starter to 12.75% and perform experiment #4 again.
Experiment #5 is also thrown away since first day was in sub-freezing temperatures. Dough was under fermented with 13 hour rise at 72*



Title: Re: Re: Cold fermenting in refridgerator with sourdough
Post by: R2-Bayou on February 03, 2013, 11:55:30 PM
I wonder if a long room temp bulk ferment followed by balling then cold retarding would produce a more friendly use window but still provide spring, strength, and flavor...
Title: Re: Re: Cold fermenting in refridgerator with sourdough
Post by: dellavecchia on February 04, 2013, 06:53:11 AM
I wonder if a long room temp bulk ferment followed by balling then cold retarding would produce a more friendly use window but still provide spring, strength, and flavor...

Yes, absolutely. This is common practice.

John
Title: Re: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 04, 2013, 07:36:25 AM
Yes, absolutely. This is common practice.

John

It is?? Well I guess there is no need for this experiment to continue then. Can you share any links for my knowledge?
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: bfguilford on February 04, 2013, 09:13:34 AM
JD: I have been experimenting with Ischia in a NY style pie, but haven't tried such extended cold fermentation times. I maxed out at 66 hours in the fridge. What I noticed when I did the cold ferment was that I didn't see much increase in the volume during the fridge time, but I got very good oven spring and decent browning on cordierite, and now even better on soapstone.

Here's the thread that I have going on it: http://www.pizzamaking.com/forum/index.php/topic,21530.20.html.

Barry

Title: Re: Cold fermenting in refridgerator with sourdough
Post by: norma427 on February 04, 2013, 09:39:33 AM

JD,

This thread is where I experimented and used the Ischia starter in a Lehmann dough and cold fermented the dough for a extended period if you are interested.

http://www.pizzamaking.com/forum/index.php/topic,11700.0.html

Norma
Title: Re: Re: Cold fermenting in refridgerator with sourdough
Post by: dellavecchia on February 04, 2013, 09:48:31 AM
It is?? Well I guess there is no need for this experiment to continue then. Can you share any links for my knowledge?

Retarding is done quite often in the bread making world, home and commercial alike. The basic premise is to extend the fermentation to bake at a specific time. This allows commercial operations that rely on room temp fermentation to have a consistent product and baking schedule. You do your bulk, shape and then retard. This slows down the fermentation activity, adds flavor character from LAB, and mitigates changes in humidity and temperature that would otherwise speed up or slow down a room temp ferment.

One factor you should consider is the amount of starter needed to make retardation happen as it is intended. Lower than 10% of flour may not be enough to generate the amount of activity needed before being placed in cold storage. All things being equal, the dough formulation informs the workflow, not the other way around.

Link to fresh loaf articles on retarding (http://www.google.com/search?client=safari&rls=en&q=bread+making+retard&ie=UTF-8&oe=UTF-8#hl=en&safe=active&client=safari&tbo=d&rls=en&q=+site:thefreshloaf.com+bread+making+retard&sa=X&ei=5MYPUdDuBqeo0AHMnIHAAw&ved=0CEwQrQIwAQ&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.&bvm=bv.41867550,d.dmQ&fp=fbfd24a6e1f5f7c0&biw=1542&bih=902)

John
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: mitchjg on February 04, 2013, 10:37:04 AM
Sorry, if I may be slightly off the specific topic .  I often use Jeff Varasno's workflow to prepare my doughs.  He describes the use of yeast (in addition to the starter at 8%) as optional.  Pftaylor also uses a bit of yeast to boost the starter.

Neither does a bulk rise, they ball and refrigerate (although the workflow has a lot of waiting times they are not very long for starter).  The recommended warm up time is only about 80 or 90 minutes.

I have found that if I do not use the "optional" yeast, I do not nearly the rise I want.

So, I have been thinking of modifying their workflow with a bulk rise for a couple of hours and then proceeding. 

Thoughts?
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: dellavecchia on February 04, 2013, 11:05:00 AM
Sorry, if I may be slightly off the specific topic .  I often use Jeff Varasno's workflow to prepare my doughs.  He describes the use of yeast (in addition to the starter at 8%) as optional.  Pftaylor also uses a bit of yeast to boost the starter.

Neither does a bulk rise, they ball and refrigerate (although the workflow has a lot of waiting times they are not very long for starter).  The recommended warm up time is only about 80 or 90 minutes.

I have found that if I do not use the "optional" yeast, I do not nearly the rise I want.

So, I have been thinking of modifying their workflow with a bulk rise for a couple of hours and then proceeding. 

Thoughts?

Yes, a bulk rise at room temp will help. Be aware, though, that active fermentation at room temp may reduce the amount of time the dough will be viable even in cold storage. Retarding is meant to be used for less than 24 hours in my opinion. But if you balance the amount of starter you might be able to get a longer ferment.

John
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 04, 2013, 11:08:04 AM
JD: I have been experimenting with Ischia in a NY style pie, but haven't tried such extended cold fermentation times. I maxed out at 66 hours in the fridge. What I noticed when I did the cold ferment was that I didn't see much increase in the volume during the fridge time, but I got very good oven spring and decent browning on cordierite, and now even better on soapstone.

Here's the thread that I have going on it: http://www.pizzamaking.com/forum/index.php/topic,21530.20.html.

Barry



Barry. I have kept up with your thread (pies look great by the way!)... but it looks like your lowest temperature is 55 degrees? EDIT: Went back and noticed you did a 40* Fridge ferment. My experiment is to determine whether fridge temps allow yeast to go nearly 100% dormant, I believe 55 is a bit too high for dormancy.

Looks like you got great results with 4% starter and a few days of fridge temps. This is opposite of my results so I suppose I need to keep experimenting.

Additionally my latest experiment was using steel, which in theory has a greater conductivity than cordierite or soapstone & would promote exceptional spring. I did not see that with my last dough, which is why I'm wondering now if fridge temps kill a certain % of the yeast?

JD,

This thread is where I experimented and used the Ischia starter in a Lehmann dough and cold fermented the dough for a extended period if you are interested.

http://www.pizzamaking.com/forum/index.php/topic,11700.0.html

Norma

I am quite familiar with your work Norma! I hope to be able to make a pizza close to your abilities one day. I apologize for not reviewing the 15 pages of materials ;D, but could you tell me if you ever did a long cold ferment (4+ days) to see if the yeast went into dormancy and had no effect on the final warm rise?

Retarding is done quite often in the bread making world, home and commercial alike. The basic premise is to extend the fermentation to bake at a specific time. This allows commercial operations that rely on room temp fermentation to have a consistent product and baking schedule. You do your bulk, shape and then retard. This slows down the fermentation activity, adds flavor character from LAB, and mitigates changes in humidity and temperature that would otherwise speed up or slow down a room temp ferment.

One factor you should consider is the amount of starter needed to make retardation happen as it is intended. Lower than 10% of flour may not be enough to generate the amount of activity needed before being placed in cold storage. All things being equal, the dough formulation informs the workflow, not the other way around.

Link to fresh loaf articles on retarding (http://www.google.com/search?client=safari&rls=en&q=bread+making+retard&ie=UTF-8&oe=UTF-8#hl=en&safe=active&client=safari&tbo=d&rls=en&q=+site:thefreshloaf.com+bread+making+retard&sa=X&ei=5MYPUdDuBqeo0AHMnIHAAw&ved=0CEwQrQIwAQ&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.&bvm=bv.41867550,d.dmQ&fp=fbfd24a6e1f5f7c0&biw=1542&bih=902)

John

Thanks for the info John. It seems that many people are using cold ferment with a standard time in mind (such as 1-2 days). I'm attempting to prove that fridge temps allow doughs with natural starters to go into near-complete dormancy, which would allow for a much more flexible pizza making schedule if true (up to 2 weeks until dough breaks down due to enzymatic reactions which seemed to be the case on my 14 day dough)


Sorry, if I may be slightly off the specific topic .  I often use Jeff Varasno's workflow to prepare my doughs.  He describes the use of yeast (in addition to the starter at 8%) as optional.  Pftaylor also uses a bit of yeast to boost the starter.

Neither does a bulk rise, they ball and refrigerate (although the workflow has a lot of waiting times they are not very long for starter).  The recommended warm up time is only about 80 or 90 minutes.

I have found that if I do not use the "optional" yeast, I do not nearly the rise I want.

So, I have been thinking of modifying their workflow with a bulk rise for a couple of hours and then proceeding.  

Thoughts?

mitchjg: Varasano's recipe is exactly why I've decided to start this experiment. He claims that only 1-2 hours is required for final proofing of the dough after a cold ferment. My findings have always been completely opposite, that the dough was completely under fermented. I never use commercial yeast as a booster, so I believe cold "fermentation" doesn't quite exist with a natural starter
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 04, 2013, 11:20:28 AM
Sorry, if I may be slightly off the specific topic .  I often use Jeff Varasno's workflow to prepare my doughs.  He describes the use of yeast (in addition to the starter at 8%) as optional.  Pftaylor also uses a bit of yeast to boost the starter.

...

I have found that if I do not use the "optional" yeast, I do not nearly the rise I want.

It's very likely that Jeff's "starter" was primarily a culture of baker's yeast to start with (perhaps there is other flora in it as well), so what is optional for him in terms of adding additional baker's yeast in a cold environment may not necessarily be optional for you using a bona fide SD culture as you have obsered.

I don't understand the fascination with putting SD-leavened dough in the refrigerator. If you need to do it to make timing work, that one thing, but IMO, it results in sub-optimal flavor and texture. Jeff may have needed the fridge to get the flavor he wanted out of baker's yeast, but you don't need the fridge to get flavor out of SD - rather, it works against you in this regard.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 04, 2013, 11:43:42 AM

I don't understand the fascination with putting SD-leavened dough in the refrigerator.

Purely for a more flexible schedule. My "control" dough (no cold ferment) was superior as far as handeling is concerned, but lacked flavor & color. I'm sure if I followed a schedule similar to yours (low % starter, 65* for 2-4 days) I would find that perfect balance and make a perfect pizza.

I like to try new things and I think it would be beneficial if I could find a dough recipe that stands up to some time in the fridge, and be able to pull it out 24 hours before pizza night, regardless if it were 2 days or 2 weeks after I made the dough. I'm not suggesting a cold fermented dough will be superior to a "warm" fermented dough. Hope that's clear it up a bit.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 04, 2013, 11:56:10 AM
Purely for a more flexible schedule. My "control" dough (no cold ferment) was superior as far as handeling is concerned, but lacked flavor & color. I'm sure if I followed a schedule similar to yours (low % starter, 65* for 2-4 days) I would find that perfect balance and make a perfect pizza.

When you do, please share your secret. I've been trying for a few years now, and I have not made a perfect pizza yet.  ;)

Quote
I like to try new things and I think it would be beneficial if I could find a dough recipe that stands up to some time in the fridge, and be able to pull it out 24 hours before pizza night, regardless if it were 2 days or 2 weeks after I made the dough. I'm not suggesting a cold fermented dough will be superior to a "warm" fermented dough. Hope that's clear it up a bit.

I guess I just see things differently. What is the benefit? Convienience? I don't see convienience as an acceptable tradeoff for quality. Just my $0.02.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 04, 2013, 12:01:05 PM
When you do, please share your secret. I've been trying for a few years now, and I have not made a perfect pizza yet.  ;)

Your pictures and sticky's would suggest otherwise!


I guess I just see things differently. What is the benefit? Convienience? I don't see convienience as an acceptable tradeoff for quality. Just my $0.02.

I understand what you mean. I suppose since I have a lot of unknowns in my near future where I'm sure my schedule is going to vary day to day and be highly subject to change, I don't want to risk throwing away a doughball because we had to make last minute changes.

I guess I'm looking for a family friendly recipe where things just don't go as planned. I know it will still be better than ordering from your local chain.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 04, 2013, 12:04:02 PM
I know it will still be better than ordering from your local chain.

No doubt!
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: bfguilford on February 04, 2013, 03:45:47 PM
Barry. I have kept up with your thread (pies look great by the way!)... but it looks like your lowest temperature is 55 degrees? EDIT: Went back and noticed you did a 40* Fridge ferment. My experiment is to determine whether fridge temps allow yeast to go nearly 100% dormant, I believe 55 is a bit too high for dormancy.

Looks like you got great results with 4% starter and a few days of fridge temps. This is opposite of my results so I suppose I need to keep experimenting.

JD: Thanks. Just to clarify, the 4% was in a cooler that was around 64 degrees. The fridge ferments were between 17 and 20 percent starter.

Barry
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: norma427 on February 04, 2013, 06:40:06 PM

I apologize for not reviewing the 15 pages of materials ;D, but could you tell me if you ever did a long cold ferment (4+ days) to see if the yeast went into dormancy and had no effect on the final warm rise?


JD,

I did use a 25 day old cold fermented milk kefir dough ball to make a pizza.  The dough ball was warmed-up for 3 hrs.  If you are interested I posted about it at Reply 218 http://www.pizzamaking.com/forum/index.php/topic,12173.msg120993.html#msg120993 and the following posts.

Norma
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 04, 2013, 08:01:54 PM
Thank you for the information Norma. I find the following quote very interesting:

John,

Thanks for saying the 25 day milk kefir pizza was picture perfect.  :) I never would have thought any dough ball could be cold fermented for 25 days and still have enough yeast in the dough to leaven a pizza.  Somehow it must be something in milk kefir that keeps the dough from fermenting too fast.  I will have to do more experiments using milk kefir.

Norma

I still stand by my suspicions that yeast go into dormancy while in the fridge. I know you attribute the extended fermentation to the milk kefir, but would you consider my statement to possibly be true, also considering you did nearly a 50% preferment?!
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: norma427 on February 04, 2013, 08:25:29 PM
Thank you for the information Norma. I find the following quote very interesting:

I still stand by my suspicions that yeast go into dormancy while in the fridge. I know you attribute the extended fermentation to the milk kefir, but would you consider my statement to possibly be true, also considering you did nearly a 50% preferment?!


JD,

I really donít know, but donít think starters go completely dormant while in the fridge, unless the temperature is too low.  I know I used a high amount of the milk kefir in that dough.  Maybe someday I will have to do another experiment with the Ischia starter and a lower amount of preferment.  I know other members methods of control temperature fermenting do give better results.

You might be right that a lower amount of starter in a dough will go dormant in the fridge.

Norma
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 04, 2013, 10:08:14 PM
JD,

I really donít know, but donít think starters go completely dormant while in the fridge, unless the temperature is too low.  I know I used a high amount of the milk kefir in that dough.  Maybe someday I will have to do another experiment with the Ischia starter and a lower amount of preferment.  I know other members methods of control temperature fermenting do give better results.

You might be right that a lower amount of starter in a dough will go dormant in the fridge.

Norma

Thank you for your additional thoughts. I think you're right that they do not go completely dormant. I'd like to find out just how much they do go dormant though.

I will continue my experimenting, mostly because I just enjoy the process. I am making a 12.75% starter dough tonight and plan to repeat experiment number 4 above. This is an assumption that a certain % of yeast have irreversible damage after being subjected to low temperatures for an extended amount of time.

JD
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 04, 2013, 10:24:47 PM
Thank you for your additional thoughts. I think you're right that they do not go completely dormant. I'd like to find out just how much they do go dormant though.

I will continue my experimenting, mostly because I just enjoy the process. I am making a 12.75% starter dough tonight and plan to repeat experiment number 4 above. This is an assumption that a certain % of yeast have irreversible damage after being subjected to low temperatures for an extended amount of time.

JD

I can't think of any basis for such an assumption.

In your #4, you wrote: "Although the dough seemed to be fully fermented, spring & color were very poor. I'm now beginning to suspect that the fridge actually damages the yeast in some way."

If the dough looked fully fermented but didn't spring, wouldn't that seem to suggest that there had been an adverse effect on the mechanical structure of the dough itself rather than on the yeast? It sounds like the yeast did their job but the dough failed.

This is what I've been trying to tell you. It's not about damage to the yeast. Extended SD cold fermentation is not good for the dough itself.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 04, 2013, 11:09:24 PM
I can't think of any basis for such an assumption.

In your #4, you wrote: "Although the dough seemed to be fully fermented, spring & color were very poor. I'm now beginning to suspect that the fridge actually damages the yeast in some way."

If the dough looked fully fermented but didn't spring, wouldn't that seem to suggest that there had been an adverse effect on the mechanical structure of the dough itself rather than on the yeast? It sounds like the yeast did their job but the dough failed.

This is what I've been trying to tell you. It's not about damage to the yeast. Extended SD cold fermentation is not good for the dough itself.


The reason I suspect yeast damage is because my 14 day ferment had great spring & color. So if that dough wasn't damaged why should the 5 day dough be damaged? I used the exact same process.

Also I should point out that the appearance of fermentation of the 5 day dough was lots of little bubbles, but it did not gain much volume.

My only explanation of the 14 day success would be that a certain percentage of yeast died out initially, and the strong survived. After 14 days the strong yeast cold fermented enough to multiply back to the amount near the original starter %, and a 24 hour warm ferment kicked off the real fermentation process.

I know it sounds crazy, but what other variable might I be missing? The only thing I've been changing is the cold temp ferment time.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 05, 2013, 09:05:57 AM
Was the dough for experiments 1-4 all made in one batch? If not, was it all made at the same time?
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 05, 2013, 09:07:39 AM
Was the dough for experiments 1-4 all made in one batch? If not, was it all made at the same time?

It was not. Same process, same materials, different day of the week.

Your point is noted.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 05, 2013, 09:35:58 AM
It was not. Same process, same materials, different day of the week.

Your point is noted.

I would say that renders the results of the experiments invalid as there is no way you could control the starter activity level nor the enzyme or acid level of the starter with suitable precision. I think it is critical that any results you want to compare come from the same batch of dough. Likewise, subsequent sets of experiments should include at least one control that has been previously tested, and if the control doesn't get the same result as in previous experiments, you must reject all of the results of the other tests in that set.

Also, if it is weak yeast dying off and stronger yeast replicating that explain the difference, shouldn't that cause you to reject your hypothesis that the yeast go virtually dormant? By "weak" do you mean genetically less fit, or simply old and tired?
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 05, 2013, 10:03:56 AM

Something else to consider: there are some key factors that determine how much energy yeast and bacteria can generate: temperature, hydration, salinity, pH, food supply and metabolic pathway (aerobic or anaerobic). In the case of a young dough, generally speaking, food supply is always high and oxygen is always low, so the others are the ones we need to be concerned with.

There are three main functions for which yeast and bacteria use energy, homeostasis (the basic cellular processes to maintain a stable environment inside the cell Ė i.e. life), growth, and division. There is a hierarchy as to how energy is spent; first is homeostasis, and only if there is energy left over, is there growth, and only if there is still energy left over, is there division. As the external environment becomes less ideal (temp too high or low, pH too high or low, salinity too high, food too low, etc.) , the less efficient the cell becomes and the more energy must be devoted to homeostasis Ė simply staying alive Ė leaving less for growth and reproduction.

Extended periods of cold hit the yeast two ways Ė lower temp and lower pH. Both require the cell to devote more and more energy to homeostasis. 100% of the energy the cell has available comes from carbohydrate metabolism, and as previously discussed, this creates CO2. If you see signs of CO2 being produced, you have energy production. This does not mean you have significant division however, and if youíre not seeing much in the way of bubbles in the fridge, itís not very likely that you have any meaningful division.

I bring this up because even if youíre right about weaker cells dying off, you probably donít have reason to believe they are being replaced by stronger cells.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 05, 2013, 12:50:07 PM
Something else to consider: there are some key factors that determine how much energy yeast and bacteria can generate: temperature, hydration, salinity, pH, food supply and metabolic pathway (aerobic or anaerobic). In the case of a young dough, generally speaking, food supply is always high and oxygen is always low, so the others are the ones we need to be concerned with.

There are three main functions for which yeast and bacteria use energy, homeostasis (the basic cellular processes to maintain a stable environment inside the cell Ė i.e. life), growth, and division. There is a hierarchy as to how energy is spent; first is homeostasis, and only if there is energy left over, is there growth, and only if there is still energy left over, is there division. As the external environment becomes less ideal (temp too high or low, pH too high or low, salinity too high, food too low, etc.) , the less efficient the cell becomes and the more energy must be devoted to homeostasis Ė simply staying alive Ė leaving less for growth and reproduction.

Extended periods of cold hit the yeast two ways Ė lower temp and lower pH. Both require the cell to devote more and more energy to homeostasis. 100% of the energy the cell has available comes from carbohydrate metabolism, and as previously discussed, this creates CO2. If you see signs of CO2 being produced, you have energy production. This does not mean you have significant division however, and if youíre not seeing much in the way of bubbles in the fridge, itís not very likely that you have any meaningful division.

I bring this up because even if youíre right about weaker cells dying off, you probably donít have reason to believe they are being replaced by stronger cells.



This is very nice information, thank you for sharing.

I understand your explanation completely, and I agree about your conclusion. I just want to share my train of thought so you understand how my brain processes this new info.


Assume 100 people are left out in a winter desert overnight with nothing but a t-shirt and shorts. Just like your yeast survival hierarchy, there is certainly a hierarchy of survival for a human being. An important note would be that every human will react to an outside environment differently. Therefore (for example) of the 100 people, 22 will die, 48 will have hypothermia and lose limbs, and the remaining 30 will survive with no major injuries.

Do yeast have the same variations in survival? I don't know. If they do it would be to a much lesser extent than humans since they are "simple" organisms.

One more thought would be that the yeast on the outside of the dougball would be subjected to lower temperatures than the inside the center of the doughball. Perhaps my "weaker" yeast are simply the yeast within 1" of the outer layer of the doughball.

I understand this is an unusual experiment with no added benefit for "big picture" pizza making. It's just something I started that I'd like to continue. I'm going to use your suggestion on my next experiment and make 1 large batch of pizza dough, divide and scale into 3 separate doughballs, then make them at 3 different times over 2-3 weeks.

I already made the 12.75% last night so I'll finish that experiment first.

Thanks again for your input.


Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 05, 2013, 01:27:54 PM
Assume 100 people are left out in a winter desert overnight with nothing but a t-shirt and shorts. Just like your yeast survival hierarchy, there is certainly a hierarchy of survival for a human being. An important note would be that every human will react to an outside environment differently. Therefore (for example) of the 100 people, 22 will die, 48 will have hypothermia and lose limbs, and the remaining 30 will survive with no major injuries.

Do yeast have the same variations in survival? I don't know. If they do it would be to a much lesser extent than humans since they are "simple" organisms.

This is where i was going when I asked "by 'weak' do you mean genetically less fit, or simply old and tired?

There are always going to be older cells that will die more quickly when stress increases, but you are talking about the other case - natural selection - survival of the fittest. Your are suggesting that there are cells with a greater ability to maintain homeostasis in colder conditions and the offspring of these cells will share that ability. You are also suggesting that the difference between the two types of cells (those that can and those that can't) is so stark that you will see a difference in only one dough-making cycle. I tend to doubt this is the case, however uf you are right, and if you were to grow a new SD culture out of the old dough and repeat the cycle a couple times, you should have a strain of SD that is super cold resistant.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 05, 2013, 01:44:21 PM
This is where i was going when I asked "by 'weak' do you mean genetically less fit, or simply old and tired?

There are always going to be older cells that will die more quickly when stress increases, but you are talking about the other case - natural selection - survival of the fittest. Your are suggesting that there are cells with a greater ability to maintain homeostasis in colder conditions and the offspring of these cells will share that ability. You are also suggesting that the difference between the two types of cells (those that can and those that can't) is so stark that you will see a difference in only one dough-making cycle. I tend to doubt this is the case, however uf you are right, and if you were to grow a new SD culture out of the old dough and repeat the cycle a couple times, you should have a strain of SD that is super cold resistant.



That's an interesting twist to my assumptions. An evolution of yeast, so to speak. This wasn't the intent of my experimentations but sounds like an interesting side-experiment. You would assume a starter that is "put to sleep" in the refrigerator (such as mine) would start to take on these attributes though. It's also the assumption that the offspring of cells actually maintain the parent cell attributes as you mentioned. I'm no microbiology expert, so I cannot comment on this claim.

Anyhow, a successful experiment of a single dough-making cycle is certainly not a reason to contact Popular Science magazine, however if the entire "cycle" is repeated many times and shows similar results, I'd start questioning the validity of my assumptions.

Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 05, 2013, 02:29:01 PM
You would assume a starter that is "put to sleep" in the refrigerator (such as mine) would start to take on these attributes though. It's also the assumption that the offspring of cells actually maintain the parent cell attributes as you mentioned. I'm no microbiology expert, so I cannot comment on this claim.

I would not make that assumption. What would be the basis? Excluding the presence of a mutagen, it is a good assumption that the offspring of cell division are genetically identical to the parent. These cultures, such as Ischia, have been around for a long time. Weaker strains should have died off long ago. This is why they generally don't change over time the way cultures you capture locally tend to change as they mature.  Why would you assume that all the yeast in your culture are not substantually similar having decended from the strongest yeast? Maybe they are not, but I don't see a basis for that assumption off the bat. 

If you're going to be scientific, your null hypothesis would be that there is not enough difference in the cells for the yeast to naturally select into a meaningfully more cold-resistant culture. It's not enough to get a result that suggests your alternate hypothesis (that the yeast culture will become more cold tolerant after exposure to colder temps) is correct. You must disprove the null hypothesis which is much more difficult.

My doubt lies in the idea that the difference is so stark between the less and more cold-tolerant cells that you will see a difference - let alone in one cycle.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 05, 2013, 02:45:21 PM
I would not make that assumption. What would be the basis? Excluding the presence of a mutagen, it is a good assumption that the offspring of cell division are genetically identical to the parent. These cultures, such as Ischia, have been around for a long time. Weaker strains should have died off long ago. This is why they generally don't change over time the way cultures you capture locally tend to change as they mature.  Why would you assume that all the yeast in your culture are not substantually similar having decended from the strongest yeast? Maybe they are not, but I don't see a basis for that assumption off the bat. 

If you're going to be scientific, your null hypothesis would be that there is not enough difference in the cells for the yeast to naturally select into a meaningfully more cold-resistant culture. It's not enough to get a result that suggests your alternate hypothesis (that the yeast culture will become more cold tolerant after exposure to colder temps) is correct. You must disprove the null hypothesis which is much more difficult.

My doubt lies in the idea that the difference is so stark between the less and more cold-tolerant cells that you will see a difference - let alone in one cycle.

Without completely de-railing this discussion, I would agree with you that all yeast cells would be 99.9% identical. But that 0.1% remaining would be the basis of evolution as we know it. While the yeast are probably 99% similar now as it was 500 years ago, I might argue that due to the process of evolution they have actually changed since then. This evolution is probably undetectable by us, but wouldn't mean it didn't happen.

Back to the topic on hand: This discussion does compliment your argument that the difference between cells would not be enough to see a difference in the big picture. To that I give you a point.


How about the argument of external yeast vs. internal yeast?  Seems a much easier pill to swallow.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 05, 2013, 03:31:33 PM
Without completely de-railing this discussion, I would agree with you that all yeast cells would be 99.9% identical. But that 0.1% remaining would be the basis of evolution as we know it. While the yeast are probably 99% similar now as it was 500 years ago, I might argue that due to the process of evolution they have actually changed since then. This evolution is probably undetectable by us, but wouldn't mean it didn't happen.

Back to the topic on hand: This discussion does compliment your argument that the difference between cells would not be enough to see a difference in the big picture. To that I give you a point.


How about the argument of external yeast vs. internal yeast?  Seems a much easier pill to swallow.

It would probably be a case of adaptation not evolution. And maybe you're right about 0.1%, notwithstanding it seems highly unlikely that 14 days in the fridge could develop that that level of difference to something you can quantify with casual observation vs. 5 days in the fridge or 1 day in the fridge.

I'm not sure what you mean by external yeast vs. internal yeast?
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 05, 2013, 03:37:16 PM
notwithstanding it seems highly unlikely that 14 days in the fridge could develop that that level of difference to something you can quantify with casual observation vs. 5 days in the fridge or 1 day in the fridge.

Yes I understand now what you've been trying to tell me, and I agree.



One more thought would be that the yeast on the outside of the dougball would be subjected to lower temperatures than the inside the center of the doughball. Perhaps my "weaker" yeast are simply the yeast within 1" of the outer layer of the doughball.


I'd like to call this the igloo effect ...
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 05, 2013, 03:47:02 PM
I'd like to call this the igloo effect ...

You might stick an instant read thermometer in one and see how long it takes the ball to equalize at the refrigerator temperature. I can't imaging it takes very long - certainly not compared to 5 or 14 days.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 05, 2013, 03:55:32 PM
You might stick an instant read thermometer in one and see how long it takes the ball to equalize at the refrigerator temperature. I can't imaging it takes very long - certainly not compared to 5 or 14 days.

The idea was that (similar to mass effect) the center of the doughball would be slightly warmer than the exterior due to activity of the yeast, and therefore never equalize.


Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on February 05, 2013, 04:38:29 PM
The idea was that (similar to mass effect) the center of the doughball would be slightly warmer than the exterior due to activity of the yeast, and therefore never equalize.

I say no chance the difference is meaningful. You've already told me that there is almost zero activity in the fridge. I doubt if it is >0.1F. Maybe if you have 40kg of dough in bulk at room temp, but not one ball in the fridge. I stand to be corrected if measurements prove me wrong.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 05, 2013, 08:05:35 PM
Well it looks like I solved the mystery of why the results from experiment #4 were out of place.

I took a digital probe thermometer to the dough to test the difference in temperature between the exterior & center of the dough. My dough temp was a blistering 31*F. I put this dough (as well as experiment #4 dough) in the lowest drawer of my fridge.

I took a temp of food sitting on the middle shelf where my previous experiments were and got 36*F. Top shelf foods were 40*F. Amazing the temperature difference. I imagine the yeast in Dough #4 was in fact "damaged" from below freezing temps.

Still going to continue my original experiment and stay on the original middle shelf (36*) from now on.


Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 19, 2013, 09:35:34 PM
I had some excellent results tonight. Probably going to stick with this recipe and see how it holds up over a few additional days fermentation.

17" NY Style using Ischia
Cut from my personal excel sheet:


   Total Weight   752.1   Grams
59.0%   Water   255.0   Grams
100.0%   Flour   432.2   Grams
3.0%           Salt   13.0   Grams
10.0%   Starter   43.2   Grams
2.0%           Olive Oil   8.6   Grams
   1   Ball(s) Desired   
   741   Gram Ball Size (with loss)   


24 hours in fridge, re-balled than 24 hours at 65*. I made the dough using GM Better for bread flour. I did an identical dough tonight but used ADY & All-trumps bromated. The results were only slightly different, where flavor was in favor of the Ischia dough, and color/dough strength in favor of the all trumps dough. Never had much luck with top crust color, but flavor completely over-shadows that flaw. Camera also isn't the best quality so crust looks more pale than it actually was.


Edit: Added picture of reheated slice in better light
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on February 19, 2013, 09:46:06 PM
Here's the results of the same formula but with All-trumps bromated + ADY
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: PizzaJerk on March 06, 2013, 12:28:09 PM
I had some excellent results tonight. Probably going to stick with this recipe and see how it holds up over a few additional days fermentation.

17" NY Style using Ischia
Cut from my personal excel sheet:


   Total Weight   752.1   Grams
59.0%   Water   255.0   Grams
100.0%   Flour   432.2   Grams
3.0%           Salt   13.0   Grams
10.0%   Starter   43.2   Grams
2.0%           Olive Oil   8.6   Grams
   1   Ball(s) Desired   
   741   Gram Ball Size (with loss)   


24 hours in fridge, re-balled than 24 hours at 65*. I made the dough using GM Better for bread flour. I did an identical dough tonight but used ADY & All-trumps bromated. The results were only slightly different, where flavor was in favor of the Ischia dough, and color/dough strength in favor of the all trumps dough. Never had much luck with top crust color, but flavor completely over-shadows that flaw. Camera also isn't the best quality so crust looks more pale than it actually was.


Edit: Added picture of reheated slice in better light

I believe that due to the re-balling, especially in the lack of presence of sugar, you will most likely always have a lack of top color. However, there are a couple of other factors you may want to consider..
1. Position of your stone in the oven (assuming you're using a home oven), a higher position would help with the top browning especially in an electric oven with a top element. You may also want to include some broiler time during the bake, that will also help.
2. For the amount of starter and basically a 48 hour ferment, I dont think there is going to be enough residual sugars left within the dough to provide the color you desire. Especially with the re-balling and lack of added sugar to your dough.

There are always a miriad of factors at play with any dough.. I hope if you consider employing these into your regimine that they work out for you. All things considered, practice (and experimentation) make perfect. You're well on your way.

You may want to have a look at member Glutenboy, I believe he employs a long ferment as well as a re-ball and has had good results. Seems along the lines of what you're doing.

Good luck,
Anthony
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: R2-Bayou on May 13, 2013, 01:35:05 PM
I had something come up right before I was about to bake this weekend, so I had to put everything on hold until later.

64% hydration, 3% active starter. 20 hr bulk room temp fermentation (~72į). Balled about 3 hours RT then put the whole flat into the fridge until I could come back to bake about 5 hours later. Normally, these dough balls would have been completely blown out and over fermented by the time I got to them if I left them at RT. The fridge slowed them down perfectly, the balls didn't merge together in the dough tray. I let them warm up for about a half hour at 70į while my LBE warmed up. When I stretched them, they were still a little cold and tricky to open up. Not a deal breaker, but took some getting used to on the first couple. After shaping they had the tell tale signs of little dough air bubbles all over the skins. These were some of the best tasting and best oven spring pies I've made in a while. I was skeptical of the fridge retarding, but it worked great. Granted, it was a short-ish retarding, but it worked great and extended my service window. No pics as I was baking in the middle of the night, but they were great.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on May 13, 2013, 01:44:21 PM
Thanks for the update!

I've since stopped using Ischia for my NY pies, but I think I recall going 2 weeks in the fridge with still very good results. The only issue at 2 weeks was poor dough strength, which just meant I had to be much more careful when opening a skin.

Does this produce an optimal pie? Probably not. But if your schedule changes, no need to toss the dough (pun intended)





I had something come up right before I was about to bake this weekend, so I had to put everything on hold until later.

64% hydration, 3% active starter. 20 hr bulk room temp fermentation (~72į). Balled about 3 hours RT then put the whole flat into the fridge until I could come back to bake about 5 hours later. Normally, these dough balls would have been completely blown out and over fermented by the time I got to them if I left them at RT. The fridge slowed them down perfectly, the balls didn't merge together in the dough tray. I let them warm up for about a half hour at 70į while my LBE warmed up. When I stretched them, they were still a little cold and tricky to open up. Not a deal breaker, but took some getting used to on the first couple. After shaping they had the tell tale signs of little dough air bubbles all over the skins. These were some of the best tasting and best oven spring pies I've made in a while. I was skeptical of the fridge retarding, but it worked great. Granted, it was a short-ish retarding, but it worked great and extended my service window. No pics as I was baking in the middle of the night, but they were great.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: DenaliPete on June 05, 2013, 08:50:46 AM
Thanks for the update!

I've since stopped using Ischia for my NY pies, but I think I recall going 2 weeks in the fridge with still very good results. The only issue at 2 weeks was poor dough strength, which just meant I had to be much more careful when opening a skin.

Does this produce an optimal pie? Probably not. But if your schedule changes, no need to toss the dough (pun intended)

JD,

What is your protocol now for your new york pies if you're no longer using ischia?
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: JD on June 05, 2013, 10:03:14 AM
JD,

What is your protocol now for your new york pies if you're no longer using ischia?

I use 0.5 teaspoon ADY per 700grams final doughball weight. I don't have a scale that accurately measures that low, but I haven't had any issues with using volume.
 
Mix using this method which I am very happy with: http://www.pizzamaking.com/forum/index.php/topic,24265.msg252106.html#msg252106 (http://www.pizzamaking.com/forum/index.php/topic,24265.msg252106.html#msg252106)

Cold ferment in fridge 2-3 days, simple punch down every 24 hours or as needed, and a tight reball 24 hours before bake. 3 day fridge ferment is my preferred timeframe, but 2 is good, 1 is a bit early.

As far as bake times & temps, I'm probably the only one here happy with a lower temp bake using steel: http://www.pizzamaking.com/forum/index.php/topic,23608.msg239730.html#msg239730 (http://www.pizzamaking.com/forum/index.php/topic,23608.msg239730.html#msg239730)


This past weekend I made a simple NY cheese pie (amongst 6 others), and my guests claimed it was way better than anything local. Of course, they're not from NY so they are probably not the best judges. I am from NY though, and I couldn't be happier with my efforts after a few years of experimenting.

Title: Re: Cold fermenting in refridgerator with sourdough
Post by: Rick_F on March 17, 2017, 02:32:56 PM
Am I late to the party???  Please pardon my extreme tardiness, and I hope I am not being redundant as there may be other threads in this website which may also explain why JD's dough had yeast leavening 14 days later.

There are probably millions of different strains of yeast in the environment, all with different optimum temperatures for their specific "thriving" conditions.  Some of them share this optimum temperature with each other, and some of them differ greatly.  What you feed the yeasts matter too, and many other factors as well, but we'll stick to temperature.

For example, in beer I sometimes enjoy a lager style beer which is "cold fermented" at the low 40's not because beer can't be brewed at other temps, but because if you want a clear, crisp, somewhat mild flavored final product then one of the many varietals of the lager yeast will be your ideal helper, and if you want that strain to be the the dominant yeast (because there certainly are other yeasts present as well, just in smaller numbers), then the conditions "it" likes should be sustained.
Other times I enjoy an Ale style beer which has more character, darker appearance, stronger, more pronounced flavors.  The yeasts that produce the by-products which determine these characteristics enjoy temperatures in the high 60's. 
One time I was brewing a Belgian style Ale (with one of the many, many strains of yeasts), and the instructions in the recipe were incorrect for temperature.  I was 10 degrees too high and it produced some terrible flavors, not from the Belgian yeast but from "another" yeast that enjoyed 80 degrees, and let me tell you it certainly "thrived"!.

JD's refrigerated dough was too cold for the ischia strain, but not too cold for another yeast (probably a lager type, if you wanted to make an assumption).  5 days was not enough for "that" yeast to reproduce enough of the wonderful by-products, but 14 days sounds about right.  The ischia activity was probably near a complete stop during the whole time.  By the way, an ale brews much faster than a lager because activity slows down at colder temps.

No mutation of the strains is happening, only the dominance of another strain is being observed.
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TWRWMOM on May 05, 2017, 05:44:10 PM
Hi! I believe this is my first post, although I've read a lot of this forum lately.

I've just thought about that and came here see if there was some information on this topic.

My train of thought was: Make a wild sourdough and freeze it: since it has many different types of living beings there, some types would survive and some wouldn't.

Feed it, maybe repeat process to make sure.

Hopefully I'd have a particular kind of yeast left, and with a huge amount of luck, one that produces good flavors.....

No?
Title: Re: Cold fermenting in refridgerator with sourdough
Post by: TXCraig1 on May 05, 2017, 05:55:51 PM
Hi! I believe this is my first post, although I've read a lot of this forum lately.

I've just thought about that and came here see if there was some information on this topic.

My train of thought was: Make a wild sourdough and freeze it: since it has many different types of living beings there, some types would survive and some wouldn't.

Feed it, maybe repeat process to make sure.

Hopefully I'd have a particular kind of yeast left, and with a huge amount of luck, one that produces good flavors.....

No?

I doubt it will work. I think in most cases, there is a dominant yeast-lactic acid bacteria symbiotic pair that pretty much does away with weaker species/strains.

Try it and see what happens. Who knows?