Is buying Ischia starter really necessary?

Started by nickr, October 25, 2013, 11:02:29 AM

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arspistorica

#40
Quote from: TXCraig1 on January 01, 2014, 10:10:35 AM
At least one strain of L. delbrueckii ssp. bulgaricus.

Ah, yes, a non-sourdough specific strain, too, as the one you're referring to is a specialist in dairy-based fermentations. (Yes, there have been strains recovered from sourdoughs, but the specific strain you're referencing -- which recently had its genome mapped -- is from continually propagated dairy fermentations; I think you'd find the strains in sourdough do not have as great an operon density as Lb SF.)
"Senza il mio territorio sarei solo un panificatore."
                                  -Franco Pepe

TXCraig1

Quote from: arspistorica on January 01, 2014, 10:13:40 AM
Ah, yes, a non-sourdough specific strain, too, as the one you're referring to is a specialist in dairy-based fermentations. (Yes, there have been strains recovered from sourdoughs, but the specific strain you're referencing -- which recently had its genome mapped -- is from continually propagated dairy fermentations; I think you'd find the strains in sourdough do not have as great an operon density as Lb SF.)

If 2011 is "recent." I never disagreed that Lb SF has the highest operon density. As far as I know it's the highest of any organism. Where we differ is when it comes to speaking in absolutes the way you do. What happens in a lab is all fine and dandy, but if the results don't carry over to the real world, their usefulness is limited. Even if everything you have written on the subject accurately reflects the relevant research, it doesn't explain the empirical results such as "sweet smell" scenairo I described in a previous post or how another member here can maintain 5 distinctly different cultures.

FWIW, here is a list of operon counts and density for Lactobacillus with complete genomes in GenBank.
"We make great pizza, with sourdough when we can, baker's yeast when we must, but always great pizza."  
Craig's Neapolitan Garage

TXCraig1

Quote from: arspistorica on January 01, 2014, 12:46:22 AM
I know you Texans are sceptical of words straying beyond more than one syllable,

I'm skeptical of people who unnecessarily complicate things.

"A genius is someone who takes a complex thing and makes it look simple. An academic does the opposite."
― Robert Fanney
"We make great pizza, with sourdough when we can, baker's yeast when we must, but always great pizza."  
Craig's Neapolitan Garage

arspistorica

#43
Quote from: TXCraig1 on January 01, 2014, 03:19:12 PM
If 2011 is "recent." I never disagreed that Lb SF has the highest operon density. As far as I know it's the highest of any organism. Where we differ is when it comes to speaking in absolutes the way you do. What happens in a lab is all fine and dandy, but if the results don't carry over to the real world, their usefulness is limited. Even if everything you have written on the subject accurately reflects the relevant research, it doesn't explain the empirical results such as "sweet smell" scenairo I described in a previous post or how another member here can maintain 5 distinctly different cultures.

FWIW, here is a list of operon counts and density for Lactobacillus with complete genomes in GenBank.

2011 (yes, I knew the year; I follow the microbiology of fermentation in general, not just sourdough) is indeed recent for LAB genomes that've been mapped.  There's a limited number done so every year, with that figure increasing as it gets closer to the present day, but it's still at a relatively slow rate.  E.g., this limits the number studies done into the pan-genomes of particular lactic-acid bacteria, and pales in comparison to those done on their eukaryotic cousins, say, for S. cerevisiae (but more are slowly trickling out, like one just published for Lb. sakei).

It's funny, the way certain people want to cherry-pick the available science to fit their needs or to interpret it in a very inexact way to fulfill their own personal worldview.  Take your predictive model, for example, based upon the very foundations we've been discussing.  This data was developed in a lab, with clear real-world results, except your extrapolation of it does not fit the wide range of doughs I use, as it doesn't account for osmotic stress, decreasing pH conditions, and, particularly, salt as expressed as ionic strength, which has perhaps the biggest impact on fermentation time outside of temperature.

Most of your "evidence" is off-the-cuff and anecdotal, odd for someone who insists on using high evidentiary thresholds.  Five starters that are different?  Well, how are they different?  In what ways, and are they rigorously maintained and recorded?  Doubtful.  If so, then let's investigate and try to fit it with what we know from the available research.  I have likely maintained more starters than most people on here, both professionally and at home, and under every conceivable permutation -- in terms of type of flours, both freshly-milled, commercially-available and even custom roller-milled; means of creation, temperature, inoculation size, and so on -- and on various parts of the globe to boot.  What's more, nearly every baker and pizzamaker I know tends to end up with similar results as what the available science shows, a near impossible coincidence to me, and my network isn't exactly small.  Are there differences between sourdoughs maintained at the laboratory and bakery level?  Of course, no one said there isn't, especially since the former conditions tend to be more aseptic, with less likelihood of cross-contaminating events.  This being said, the science is getting better, more predictive, and, in my experience, very much fits with what I do in the real world.

There has been a proper explanation proposed for how your two starters are different, which seems obvious to me or any other experienced sourdough baker, I would imagine.  The culture, whatever its make-up, shifted due to different processing conditions:  one was kept in the fridge so as to essentially halt fermentation and maintain the old regime, and the other was left to experience massive cell death, substrate depletion and increasingly oxidative and acidic conditions, allowing what was likely a sub-dominant bacteria to become dominant, one more tolerant of the end conditions it was exposed to.  This sort of shift is seen constantly in laboratories and in bakeries, and is one of the reasons researchers and professional bakery texts insist that type-I cultures maintained at ambient temperatures be refreshed on a daily basis.

Continue to be sceptical, because, despite what I say, I think scepticism is healthy and always warranted when it's substantive and impersonal, as the opposite -- blind allegiance to ideals in the absence of evidence -- makes for a much scarier world.  That being said, scepticism can blindly stumble down a similar path, when scepticism is adopted for its own sake, and thus choosing to ignore evidence from the real world.

Regardless, we both use sourdough and use it to sling pies, with very different outcomes.  This shows that even if fermentations are uniform under similar conditions, process parameters can always slightly be tweaked to end up with results that are vastly distinct and unique.  I see this as a good thing.

(For the record, I don't profess blind allegiance to the available science, as there's many areas in which I find its explanatory power to be incorrect, lacking or entirely incomplete, but, with this being said, I have found that much of the research that is available [and hasn't really been reported on in the relevant food literature] tends to be powerful, insightful, and more often right than wrong.  This is one of the reasons I began looking into the scientific aspects of pizza, bread, and so on, as there is a lot out there that can be explained but no one has really bothered putting in the legwork.  There's a tremendous gap between the science and the mainstream understanding, whereas I find this gap to be much less apparent in other food sectors, like wine- and/or beer-making, for example.)
"Senza il mio territorio sarei solo un panificatore."
                                  -Franco Pepe

TXCraig1

Quote from: arspistorica on January 02, 2014, 12:35:01 AM
It's funny, the way certain people want to cherry-pick the available science to fit their needs or to interpret it in a very inexact way to fulfill their own personal worldview.

What funny (and ironic) is the way you are trying to use that statement to take a swipe at me.  If trying to help people is fulfilling my personal world view, then you got me. I'm guilty.

QuoteTake your predictive model, for example, based upon the very foundations we've been discussing.  This data was developed in a lab, with clear real-world results, except your extrapolation of it does not fit the wide range of doughs I use, as it doesn't account for osmotic stress, decreasing pH conditions, and, particularly, salt as expressed as ionic strength, which has perhaps the biggest impact on fermentation time outside of temperature.

A lot of people want to try using a culture and don't know where to start. The purpose of the model was simply to help them find a starting point to work from. I built it to try to help people – not to try to prove how smart I am or how much information is packed into my head. That's the difference between you and me. I identify what is important and work to make things simple and useful. You unnecessarily complicate things, and what you post is completely useless.

QuoteMost of your "evidence" is off-the-cuff and anecdotal, odd for someone who insists on using high evidentiary thresholds. 

I never said my observations were anything but anecdotal. Regardless of your standards, you should be skeptical when your real world experiences differ from what someone tells you. That's called common sense. I'm not sure why you find this odd?

QuoteFive starters that are different?  Well, how are they different?  In what ways, and are they rigorously maintained and recorded?  Doubtful. 

If he wants to respond, he can. He's posted on this subject enough over the years that you should be able to figure it out with a little searching.
"We make great pizza, with sourdough when we can, baker's yeast when we must, but always great pizza."  
Craig's Neapolitan Garage

A D V E R T I S E M E N T


Steve


arspistorica

Quote from: Steve on January 02, 2014, 01:48:05 PM
Please stop with the public bickering.

Indeed.  I bid this site adieu, and would like to thank all those members who have contacted me privately or have followed the threads in which I've participated.
"Senza il mio territorio sarei solo un panificatore."
                                  -Franco Pepe

stonecutter

#47
That is a shame. It's really our loss...and your posts are very far from completely useless.
When we build, let us think that we build forever.
John Ruskin

Mal

Quote from: stonecutter on January 05, 2014, 07:44:26 AM
That is a shame. It's really our loss...and your posts are very far from completely useless.

+1

Pete-zza

Ian,

I, too, would like you to reconsider. Often I do not quite understand what you write but I think I get the drift and, with time, would perhaps get a better understanding of the factors and issues involved.

Peter

A D V E R T I S E M E N T


Wazza McG

Come on mate - come back - You're an aussie now and Kangaroo's can't go backwards.. only forward, and I still have heaps of questions you could help with - like understading enzymes better.
Cheers
Wazza McG

nickr

This was not at all what I intended with my question. Please note that the original post was older then some of the more recent conversations on the subject. I was not trying to stir up a pot of hostility.

Tampa

It is unfortunate when members "get sideways" with each other in the interest of good pizza making.  It happens on all forums and sometimes we lose good contributors.  I hope this doesn't happen here and I sincerely hope that cooler minds will prevail.

It is the nature of discussion forums.  The trouble is that readers often learn best when both sides of an argument are presented, I know that I do.  Differing perspectives are one of the things that make forums such a great learning opportunity.  I really like that contributors are judged by their words (and pie pictures) and not by age/job title/looks, etc.  Still, confrontational discussion can be a slippery slope which devolves into alienating one or both parties.  We need a safe word.  Until we have that, I would also like thank Steve for "turning down the heat" – and – equally thanks to Peter for his appeal for better understanding.  Both posts took courage, IMO.

Most of the technical discussion was over my head but maybe someday I'll catch up.  In the meantime, I greatly appreciate Craig's contributions and have learned a lot reading his many posts.  I don't remember reading many of Ian's comments, but I respect his sincere intent.
Dave

Totti

Firstly, apologies for the mega bump.

Secondly, this has to be one of those entertaining forum flame wars I have read. Not least because 99% of others don't actually understand what is going on.

Thirdly, I am too genuinely intrigued as to if I still have Ischia, or have I cultivated my own strain of something.

My Ischia doesn't seem to behave like many peoples here. It takes longer to rise, and non-feeding of 48 hours is enough to kill it.

A D V E R T I S E M E N T