The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

SFSD and Galal Question

DanAyo's picture
DanAyo

SFSD and Galal Question

How many times I’ve read and studied the Galal article I couldn’t say. Each time I struggle to learn more. When reading the paper this evening a question jumped out.

I believe this article is scientfic and when it details the PH and TTA at given times during fermentation I assume they are scientifically calculated and accurate. BUT, how can the author’s produce the chart below (page 463) without actually baking the bread? If they did bake the bread, how could it be sour when every attempt to follow this bake on TFL has failed?

Wouldn’t it be great (for sour lovers) if we could know how long and at what temp we needed to ferment or starters, levains, and doughs in order to produce the lowest PH and highest TTA and still produce a dough with strength (not degraded)? We could use these procedures, but I think 105F is too high. Also many of us have followed these procedures only to find that the bread was far from sour. Something isn’t adding up...

Is this chart valid?

Danny

dmsnyder's picture
dmsnyder

I would assume the article's authors tested the sponge, final dough and baked bread in the bakery, not in their lab. 

Did you miss the far right column? That presumably pertains to the baked bread.

As far as the basic question goes, I can only join you in wonderment and skepticism. 

One possibility is that the microorganisms in Larraburu's starter was very different from mine. I am highly doubtful of that explanation. 

Bottom line is I remain willing to trial reasonable-seeming recipes myself. I tried the Galal, et al. recipe in spite of my doubts about it. It made the worst bread I've baked in the last decade. I endorse the famous definition of stupidity: "Doing the same thing that has failed over and over and expecting a different result this time."

As for me, I'm still experimenting. My next one is proofing at the moment.

Happy baking!

David

Doc.Dough's picture
Doc.Dough

I agree and echo David's sentiment.  I tried it too, also with not good results. And I am not inclined to try again until I have a better idea about why it worked for them. But I am not working on it.  I am currently fermenting urad gota and rice to get idli batter which I thin down and fry to make dosa.  The microbiology is daunting as there are at least two interacting LAB (Leuconostoc mesenteroides, and Enterococcus faecalis) that you depend on, and they are native on the constituent legume (decorticated black matpe bean) at levels that depend on the history of the beans. Interesting and challenging. But not sourdough (I have tried using a starter and think I understand why it produces poor results).

breadforfun's picture
breadforfun

I have yet to try to make the Larraburu style bread, and never encountered the real thing because they closed not long before I moved to California. But the first thing that jumps out at me in the paper is that the proof is done at 105*F and 96% R.H.  Commercial bakeries have proofing chambers where both the temperature and humidity can be controlled. I think the extremely high humidity would be hard to maintain in a home environment.  I don’t think I have come across any literature describing the effect of humidity on dough other than keeping it from drying out. Still, 96% sounds pretty high.

The second thing is that they hypothesize about the oxygenation of the starter and/or the dough. They say longer fermentation times favor lactic acid after the oxygen is depleted. But what if in a highly oxygenated or aerated dough the initial “burst” of acid formed is acetic? The way most of us make bread, using stretch and fold or other gentle techniques, we try to minimize the oxidation of the dough. Maybe this bread needs significantly more aeration to produce the acetic acid. 

Or maybe I’m spouting a bunch of hoo-ha and speculation. 

-Brad

DanAyo's picture
DanAyo

I am bewildered by the specifics of the article, and yet we are unable to get close to duplicating it.

Maybe we got punked <LOL>

Doc.Dough's picture
Doc.Dough

But 105°F/96% not unobtainable in a production bakery environment.  I think the more important thing to consider is how long it takes for a proofing loaf to equilibrate with its environment.  I suspect that the center of the loaf never gets close to 105°F.

As for oxygenation, it doesn't matter how much air you whip into a dough, the oxygen is quickly consumed and the fermentation is anaerobic. 

And I don't believe that atmospheric oxygen is not the source of electrons for the oxidation of bread dough. If it was, you wouldn't add ascorbic acid to the dough as a slow oxidizer.

DanAyo's picture
DanAyo

Doc, you are correct about dough temperature equalizing. I have run a number of thermal charts and they all indicate a tremendous time lapse. The chart below deals with retardation, but it is also with warm proofing.

Update - I found a warm ferment.

Doc.Dough's picture
Doc.Dough

Danny - that is really good data.  What were you using for sensors (RTDs or thermocouples or thermisters, ...) and what was the sample interval and how did you capture/record it?

DanAyo's picture
DanAyo

I thought that might interest you :D

Check out Fireboard. The units are affordable and very precise. If I remember correctly, the sample interval is 30 seconds. My unit can run 6 probes simultaneously.

The data has taught me quite a bit. AND, it is what it is.

Doc, here is link to an interactive chart. Play around with it. You can zoom, get data from the timeline, etc..

https://share.fireboard.io/0647E4

Danny

Doc.Dough's picture
Doc.Dough

@DanAyo - Looks interesting.  Sample rate is one every 5 seconds (there may be a way to change that). And the sensors seem to be either RTDs or thermisters, either of which will work but RTDs have better long term accuracy.

breadforfun's picture
breadforfun

Danny,

Is there a relay output that would allow it to be used as a thermostat to control, say, a proofer? Didn't see one as an accessory.

-Brad

Doc.Dough's picture
Doc.Dough

Don't try to design one.

This is what you want for a temperature controller:

Johnson Controls A419 with hysteresis adjustment for stability.
But you still need a monitor and recorder

 

breadforfun's picture
breadforfun

Doc - Good advice, thanks. I learned many years ago not to reinvent the wheel. I actually use a small reptile heater thermostat to control my proofer, I find that it has sufficient accuracy for bread making (+/- 1˚F). But if it did serve both purposes it would mean one less instrument on the counter.

-Brad

DanAyo's picture
DanAyo

Brad, that might be possible. I say that because there is an accessory that plugs into the circuit board that turns a fan blower off and on. It is used to regulate the temperature of a bbq or smoker. You could call FireBoard and ask them. It would be a customized option, though.

I have a digital tempera5ure controller that I use in my retarder. If you look at the first chart that shows retardation you can see how the controller turns the compressor on and off. It can be set for great accuracy. Here is the link the the Johnson controller. By the way, Maurizio ises the same controller. https://www.amazon.com/gp/product/B074DBMG7D/ref=oh_aui_search_asin_title?ie=UTF8&psc=1

UPDATE - mine is similar to Doc’s. 

Johnson Controls A421ABG
breadforfun's picture
breadforfun

I have the opposite problem that you have. San Francisco is typically on the low side of 60˚s most of the year, so I don't need to cool things, just nudge them up a small notch. I think I'm pretty lucky relative to a lot of other bakers here.

-Brad

DanAyo's picture
DanAyo

Hey Brad, “I think the extremely high humidity would be hard to maintain in a home environment.”

You really must visit South Louisiana. <LOL>

Danny

breadforfun's picture
breadforfun

Haha. So if humidity is a major factor then your bread should ace it.

doughooker's picture
doughooker

Danny -

Do you have a web link to the Galal paper? Could you describe your process in detail?

I am skeptical of the 105-degree proofing temperature given in the Larraburu formula. Note that the "other" bakery used a much lower proofing temperature.

I once proofed a loaf at 105 F and couldn't tell a difference in the flavor of the baked bread compared to my previous proofing temperature of 90° F.

I once baked a loaf in my usual manner. The starter was nice and bubbly but devoid of any of the aroma I was accustomed to smelling. I baked the loaf and it rose OK, but it lacked any flavor whatsoever, not even a trace of sourness. I had baked many loaves prior to that which had a nice, sour flavor. Go figure. Maybe my starter had pooped out, but it was nice and bubbly (and aromaless) when I proofed it.

I have been told by someone in a position to know that occasionally a S.F. bakery would "lose" its starter. In that case they simply borrowed a quantity of a competing bakery's starter with the understanding that the bakery might someday be called upon to return the favor.

 

DanAyo's picture
DanAyo

Here is the link to the Galal article.

http://www.aaccnet.org/publications/cc/backissues/1978/Documents/chem55_461.pdf

Unless I attempt the Galal version of the Larraburu SD, my ferments never exceed 93F, and then only when I am pushing the LAB (lactic).

Loosing a starter. I can’t imagine a bakery not dehydrating some of their starter for a backup. I do this for every new starter I obtain. A backup is also good for retaining the original microbes in a given starter. I am of the opinion that no matter what starter I use, it will eventually conform fo my feed and environment. I have seen this with different and numerous starters that I have obtained from all over the states. After a while they are all indistinguishable. But a backup of the original will bring the characteristics back to when I first got it.

No mater what starter I get, it will become a Danny Ayo starter in short time. At least, that is what I believe...

Dan

doughooker's picture
doughooker

Ah, yes. I'm quite familiar with that paper.

Table II was very useful in concocting my starterless formula. Note that in the baked bread:

Lactic acid: 97.22

Acetic acid: 31.31

Again, acetic acid is vinegar. Lactic acid is the dominant flavor in SFSD.

Doc.Dough's picture
Doc.Dough

smell in SFSD, because it has a lower molecular weight and thus a lower vapor pressure at every temperature than lactic acid.  You can taste acetic acid too and it contributes to TTA so you count both when you measure TTA.

doughooker's picture
doughooker

"I can’t imagine a bakery not dehydrating some of their starter for a backup."

They may have been unsure about whether they could reconstitute a dehydrated starter. They may have figured that with a half-dozen bakeries in town making essentially the same product, it would be easier to borrow some from a neighbor.

The Galal paper studies the Larraburu bakery. Does your process differ at all from the Larraburu process posted here by doc.dough?

I will follow the suggestion of Mike Giraudo and try an extreme-long dough proof, like 24 - 48 hours, and see how it comes out. Right now I am making new starter so it will be a week.

I still prefer the starterless method for consistency and reliability.

Also keep in mind that Larraburu turned out a  couple of thousand loaves per day, so they simply didn't have time for extremely long proofing times with employees on the clock.

Doc.Dough's picture
Doc.Dough

You don't need a long time to rebuild a production quantity of starter, but you do need time. At elevated temperatures you can get a doubling time of about 2.5 hrs, which means that you can get almost 10 doublings in a day or a factor of 1024 or roughly a factor of a million in two days. So to "lose a starter" perhaps means that a batch was not fed correctly or was contaminated and had to be trashed and rebuilt from the stuff in the refrigerator. Nobody would dehydrate starter (I don't think) unless it was a better solution than simply taking a sample to the refrigerator once a day or really once a week is enough.  A one gram reserve could be built up to 1000Kg in two days so borrowing a one day supply might not be a big deal, but I suspect that each starter is sufficiently unique that the baker wants to use his own even if it is micro-biologically identical to his competitor's.  He doesn't believe that.

doughooker's picture
doughooker

Math notwithstanding, it's a business. You're expected to deliver thousands of loaves to paying customers each day. No starter, no bread, no payment. Time is of the essence in getting production going again. Time, as they say, is money.

Let's say Larraburu uses brand "x" flour and Parisian uses brand "y" flour. Let's say Larraburu borrows some starter from Parisian. After a few days in the Larraburu bakery being refreshed with brand "x" flour, after a while it'll be Larraburu starter again, not Parisian.

David R's picture
David R

Are people here (not me) simply avoiding one of the potential conclusions that might be made, because of a little star-struck-ness and/or false modesty?

ISTM not at all far-fetched to think there might be half a dozen (or more?) people participating on this site who are more knowledgeable about bread in general than Larraburu's best people ever were. And not far-fetched either, to think that some of said hyper-knowledgeable people (who - to be fair - don't have a plant schedule to stick to and several busloads of employees to pay) might be habitually making better bread than Larraburu ever could.

Doc.Dough's picture
Doc.Dough

I am interested as I don't recall seeing it explained before.

Is there a link to where you have documented it?

doughooker's picture
doughooker

"What is your "starterless method"?

I am interested as I don't recall seeing it explained before.

Is there a link to where you have documented it?"

I am making a boule as we speak.

http://www.thefreshloaf.com/node/49375/san-franciscostyle-sour-bread

Doc.Dough's picture
Doc.Dough

@doughooker - Thanks for spending the time to work out the details.  I suspect that a large fraction of "SFSD" on the market shelves is made this way. I look forward to trying the technique.

And there are other things that would benefit from a little extra lactic acid on occasion ( I am thinking of quick pickles and dosa). 

If you are a pickle fan and like them really crisp, try soaking your vegetables in a 1% calcium lactate solution for a minute or two before you put them into brine. I know of no reason why the results should be more crisp than the fresh vegetables, but my impression is that there might actually be an improvement (which I don't understand but I also don't have a good test method to verify/refute).

 

doughooker's picture
doughooker

"I suspect that a large fraction of 'SFSD' on the market shelves is made this way."

The supermarket sourdough I described adds fumaric acid to the mix. I refuse to do this because it is not present to any significant degree in naturally-fermented SD.

It fools the undiscerning public, though.

doughooker's picture
doughooker

"there might be half a dozen (or more?) people participating on this site who are more knowledgeable about bread in general than Larraburu's best people ever were."

Interesting question.

It's a different era.

San Francisco sourdough had never been studied until the USDA studied the Larraburu, Parisian, Colombo, Toscana and Pisano bakeries in the late 1960's. Some people in Europe had studied sourdough prior to then.

Nowadays we have the benefit of all sorts of scientific studies, and commercial bakers benefit from advances in food technology. The recipes and baking techniques used at the SFSD bakeries were developed long before this scientific know-how came into existence, before scientists were looking at bacteria through microscopes and measuring pH.

Better than Larraburu? I don't know. Regarding my own starterless formula, I think it compares very favorably in flavor and is more dependable than the traditional method. It took some out-of-the-box thinking and would not have been possible without the USDA and subsequent studies.

All that said, there is still stuff on store shelves and in bakeries purporting to be sourdough that isn't worth a damn.

doughooker's picture
doughooker

"acetic acid is the dominant smell in SFSD"

Most definitely not in the breads I'm familiar with.

Pick up a loaf of Acme and see if you smell vinegar.

doughooker's picture
doughooker

Is this the Galal recipe you guys are having trouble with?

The starter sponge consists of 100 parts of clear flour (14% protein), approximately 50 parts of water, and 50 parts of the starter sponge. The ingredients are mixed and fermented for 9-10 hours at 80°F. The bread dough is made by mixing 100 parts flour, 12% protein, 60 parts of water, 15 parts of sponge, and 1.5-2% salt. The dough rests 1 hour and then is divided, molded, and deposited on canvas dusted with corn meal or rice flour. The dough is proofed for 4 hours at 105°F (41°C) and 96% relative humidity and baked at 420°F (216°C) for 40-50 min.

Note that it uses a stiff sponge. I have had no luck with this recipe, either, when a stiff sponge is used.

I have had success using a liquid starter of 133% hydration, however. As an infrequent baker I keep a quantity of this liquid starter in the fridge and make it up 8 hours prior to baking. I replenish the storage starter as needed.

Despite using a liquid starter, the final dough hydration is about 60%.

The finished bread has a nice lactic-acid flavor but not as much "punch" as I would like.

The starterless recipe is still my preferred method.

DanAyo's picture
DanAyo

I have a question. The Galal paper instructs us to proof the dough for 4 hours at 105F (41C). It is my understanding that the LAB will decrease when the temp exceeds 93F. Is this correct?

And if it is correct how can 105 be beneficial?

Dan

Doc.Dough's picture
Doc.Dough

Gänzle's model suggests that the LAB replication rate slows to zero at 41°C, but says nothing about acid production rate.  And if there is anything you should appreciate about a math model is that the extreme points are not where you want to extrapolate from.  Where did you get the 93°F value for some kind a of "decrease" and what were the specific words used to describe that point.

We do know that while LAB replication stops somewhere around pH=3.5, the acid production does not, and in fact continues for quite a while below that value. I would expect the same behavior near the upper end of the temperature band as well.  The chemistry goes faster at higher temperatures until some limiting factor gets in the way and slows things down.

DanAyo's picture
DanAyo

Doc, how do the acids continue to increase when the LAB decrease? As I think about it I know this to be true, but I don’t understand it. If a starter is left on the counter unfed for a few days, it will become super pungent (sour?). What is going on? Maybe because of the death of the microbes?

How are acids produced in a bread dough? In an effort to learn I consulted Mr. Google. How is wish I could understand and and recall THIS INFORMATION.

What is Type III sourdough? It looks like it is sed for flavor only.

Danny

Lots of questions, I know...

Doc.Dough's picture
Doc.Dough

@DanAyo – can you point to something I wrote that said that the LAB decreases?  I don't believe that occurs in any dough you are likely to bake (until it goes to the oven).

The LAB continue to produce acid even after they have stopped replicating so TTA continues to rise even if the numeric density of bacteria remain the same.  As a result the pH will continue to decline somewhat (but remember that pH and TTA do not measure the same thing).

A Type III sourdough is (as explained in the post you pointed to) just dried starter with no living cells.  It is used as a source of acidity to make a sour bread using commercial yeast (this is exactly what @doughooker is doing by adding lactic acid and vinegar to his dough).

As for how the LAB make acid, I suggest you consult some of Debra Wink's exceptional posts on the microbiology of sourdough.  You can find one of them here

DanAyo's picture
DanAyo

Doc, Have I got this right. The LAB quite reproducing @ >93F but they are still alive and well and making acid.

Dan

”can you point to something I wrote that said that the LAB decreases?” I am not aware of reading anything you wrote about that. The idea came from Debra’s chart about yeast maxing at 84F and LAB @ 93F.

Doc.Dough's picture
Doc.Dough

the LAB that he studied stops replicating at around 41°C (105.8°F). @DanAyo - I don't know where your 93°F value came from.

You can easily run an experiment in which you ferment at 30°C to build up the population then increase the temperature to 45°C for a few hours to test the hypothesis that they all die off at that temperature.  If you then use that as seed for a new batch, you will discover that it is pretty active.  To check on the acid production you need to be able to run a titration to measure TTA on samples taken at the point where you raise the temperature and then after a few hours of growth at the higher temperature.  My data shows that acid continues to be produced until about the point where the sugars should be depleted (I ran it for about 36 hrs and the rate of acid production slowed down but never came to a complete halt before I terminated the run).  This is easier to run if you do it with a very liquid starter (200+% hydration).  The hardest part is to develop your skills at sample preparation and titration to the point where you can run TTA tests on the same sample repeatedly and get the same results to 3 significant digits.  I found it time consuming, tedious and expensive to acquire the capability.

doughooker's picture
doughooker

The 4 hours at 105F proof comes from the Larraburu formula. With the vast amount of bread they baked every day, it makes sense that they would do whatever they could to reduce the proofing time and move as many loaves per day as possible.

"Gänzle's model suggests that the LAB replication rate slows to zero at 41°C, but says nothing about acid production rate."

That is very illuminating.

These bakeries refreshed their sponges every 8 hours, after which it was immediately proofed and mixed in with the dough. I'm thinking the home baker doesn't refresh his sponge every 8 hours and immediately proof it and bake with it. Maybe that's why people have disappointing results with stiff starters? Or not?

DanAyo's picture
DanAyo

Doughooker, 105F would definitely speed production. My understanding of the Larraburu SD is that it produces a very intense flavor. It seems to me that a short fermentation would not produce that intense flavor. I was intrigued with the 105F proof when I first heard of it, but a number of test bakes never produced a high degree of acid :-(

The only way that I know to produce a prominent “sour” (acetic, lactic, or combination) flavor is by long fermentation, either cold or warm. But, the enemy of long fermentation is dough degradation and/or over proofing.

It would be great to learn another method that would increase the LAB in shorter time. I have played with the idea of using an extremely acid mother dough, but have not been successful. 

Danny

David R's picture
David R

Dough at some lower temperature, put into a 105° environment, will take some period of time to reach an interior temperature of 105°.

Doc.Dough's picture
Doc.Dough

Lets follow the Laraburu process through the various stages and attempt to track what is going on.  First the stored sponge is refreshed at ratio of 1:1:2 [sponge: water: flour] (which produces a new sponge at 50% hydration).  It then ferments for 8 hrs and must replace the numeric density of both the yeast and LAB to the values that were in the original sponge (so if the initial density is 10E7/gm for LAB and it is diluted by a factor of 4, it must grow back from 2.5x10E6/g to 10E7/g over 8 hours).

This means that the growth rate corresponds to a doubling time of about 4 hours which is not especially high.

Dough is then made from 100 parts flour, 60 parts water, and 15 parts sponge at 50% hydration (so there are 5 parts water + 10 parts flour in the sponge) thus in the final dough the hydration is 70/105 = 66% and there is 9% pre-fermented flour in the dough.  Note that we don’t know what the sponge propagation temperature is but if we use Gänzle’s model to figure it out (assumption here) the answer turns out to be around 20 - 21°C or 68 - 70°F which is not unreasonable for the indoor temperature in a San Francisco bakery (the details depend on whether you are using the yeast or the LAB population as the end point) and this is reasonable for propagation of the species we think we care about.

The dough is bulk fermented for an hour (again we don’t know what temperature the final dough was mixed to), then divided, shaped and final proofed for 4 hours in a warm environment at high humidity.  At 66% hydration and with a flour containing 14% protein, it would not be unreasonable to mix to a fairly warm dough temperature.  Over four hours in an environment where the temperature at the outside of the loaf goes up while the center stays pretty much fixed, the dough will do whatever a dough does that is mixed with only 10% pre-fermented flour.  This is where you can run a series of tests to see what temperature you need to have when the dough comes out of the mixer if it is going to BF for one hour and then be divided/shaped and proofed for 4 hrs at 105°F and be ready for the oven at that point.

We can see from the amount of the various acids at the measured points what the approximate dilution was from sponge to dough as well as how much they increased during the final proof. It is perhaps worth noting that the lactic and acetic acids increased very quickly from dough mixing to the 3 hr point of final proof, but did not increase by the same percentage during the last two hours of proof prior to oven entry.

The TTA values reported have been corrected to dry weight of the ingredients and thus are not directly comparable to current methods which report values per gram of levain, dough, or bread crumb.

 

 

Abe's picture
Abe

coming from a complete novice point of view, however...

This tells us only the PH level which might not be the only deciding factor in taste.

Since all starters have their own dominant acid producing bacteria, and there are many, does the PH level being the same in two sourdough breads from different starters mean they'll have the same taste?

We might just have to be happy with the starters we're given. The yeast and bacteria choose us!

Then you have to take into account the flour. Try as you might but durum flour doesn't make a tangy tasting bread even if you kept everything the same as a bread flour sourdough.

I quite like not over thinking the process too much. Learning to bring out the best in a bread by baking is not quite the same as studying graphs.

Doc.Dough's picture
Doc.Dough

Your taste mechanism is detecting the concentration of acid, not the concentration of hydrogen ions, and because both lactic acid and acetic acid are weak acids (which means that they are not fully ionized in solution) there is a difference.

TTA measures the total quantity of acid in the dough (ionized or not), while pH is a measure of H+ concentration.  It is usually reported as lactic acid equivalent per gram of (starter/dough/bread crumb) depending on what you are testing) though the standard procedure would have you report the number of ml of 0.1N NaOH required to bring a specific sample size up to a final pH of 6.6 (or 8.6 depending on what you are reading - it is not a big difference). And some papers report the results in micro-equivalents of acid/per gram of dry matter rather than per gram of starting material. So you have to dig deep to know what is being reported, and generally can't compare values across sources without a lot of work and some accompanying assumptions.

Abe's picture
Abe

and that is what I was trying to say in a round about way. PH level is not the full story.

Does this table then really not have much meaning. And why no matter what do some starters not produce bread which are tangy. Or not as much as other starters, no matter what. And why do some flours, even when treated the same way, always end up being sweeter than others?

Starters, or healthy starters, should all come in at near enough the same PH level. Just like starters will only cultivate little critters that can inhabit starters and while varied are certainly limited. When you mix flour and water together it'll sort itself out into becoming a viable starter by lowering the PH level to a starter range and supporting yeasts and bacteria that make a sourdough starter what it is.

Doc.Dough's picture
Doc.Dough

I don't see the referenced table.

As for the characteristics of different starters, I suggest you browse here to get some perspective on what is in a "typical" starter.  My interpretation is that there are a lot of different yeasts and LAB species in just about every starter and your refreshment practices will favor one or more of them and over time they will come to dominate the culture. Think of it as evolution at work.  More of a given type means more total DNA replications which presents more opportunities for genetic change which occasionally yields a variant that out competes the previously dominant strain. Though this also happens (at a proportionately lower rate) for the minor constituents (which still gives them an opportunity to deliver a breakthrough adaptation).

dmsnyder's picture
dmsnyder

Why the focus on Larraburu Bros. bread? Many of my generation grew up eating it, and it became their standard for what SF sourdough should be. On the other hand, for many others the focus stems from the fact that Larraburu's process is the best documented in a more or less scientific fashion.

How did Larraburu Bros. SF SD compare to other contemporary bakeries' SF SD? I cannot speak from personal experience, because my family always bought Parisian Bakery's bread. However, from descriptions of those who ate Larraburu Bros. bread regularly, it had a relatively mild, lactic acid-forward flavor profile, compared to the acetic acid tang of Parisian and (even more so) Boudin.

The high temperature fermentation routine described for Larraburu is consistent with lactic acid dominance, at least  up to 90ºF. I don't know what's happening at 105ºF. 

Optimal fermentation temperature is 74-80ºF. Michel Suas says 77ºF is optimal, if you have to choose a specific temperature ("Advanced Bread and Pastry," pp. 95-96.)

David

Doc.Dough's picture
Doc.Dough

I don't know that I ever knowingly ate Larraburu bread. We always got Paisano because their bakery was a couple of doors down from the laundromat we used.  They had both "sourdough" and "sweet dough" styles for sale.  And I don't remember their sourdough version as being as strongly acidic as is currently offered as representative of SFSD. But the fog of time clouds everything from that long ago.

doughooker's picture
doughooker

"Why the focus on Larraburu Bros. bread?"

It is the subject of the Galal study after having been studied by the USDA several years earlier, along with four other breads. It is certainly the best-documented as you note.

I'm sure the sales figures are long gone, but maybe it was the best-selling SD at the time?

"from descriptions of those who ate Larraburu Bros. bread regularly, it had a relatively mild, lactic acid-forward flavor profile"

Larraburu was anything but mild. It had a lot of lactic-acid "punch". Today's Acme sourdough has the same lactic-acid tanginess but as I have noted many times, it is significantly milder than Larraburu. I had to recall the flavor of Larraburu in developing my starterless recipe.

One wonders if the USDA still has the research materials from their 1969 sourdough study. That might provide some information on Parisian, Colombo, Toscana and Baroni.

My mother only bought Larraburu until the bakery closed in May, 1976, at which time she switched to Colombo. The closure of the Larraburu bakery got a lot of local press coverage at the time, as if somebody had stolen the Golden Gate bridge :)

Larraburu was de rigueur at my mother's family's gatherings in Hollister. A couple of loaves would be smeared with garlic butter and heated.

That and a Jell-O salad.

David R's picture
David R

I suspect that the shock (and the press coverage) over its sudden & unexpected closing probably has a lot to do with it. Not only is it not there anymore, it's famously not there anymore.