Poolish or biga???

[fabio]

I typically make a dough like this:

100% Caputo Pizzeria
64% Water
2.8% Salt
1.75% Camaldoli Starter

I do a ~21hr bulk rise, make balls, then 3-4hr individual rise. My question is this: should the starter be in poolish form, or in biga form? Does it matter?

I have always done it using a poolish, but it occurred to me recently that bigas are often used to improve the gluten structure in breads and the like, and the traditional "criscito" or old dough would obviously be closer to a biga than a poolish. So I decided to try it to see if it would make a difference. Unfortunately, I was forced to change several other variables as well; most notably, I ran out of Caputo, so I used Five Roses AP. I also had to make 24 pizze, so in lieu of making several batches, I made one big hand-kneaded batch. Finally, I usually do an autolyse with all the ingredients (but only 75% of the flour), but this time I did only the flour and the water. The final results, by the way, were spectacular, especially considering I used AP flour. I just have no way of knowing if using a biga contributed to that or not.

I don't know when I will have another opportunity to experiment with this more, so I humble myself before you, the experts, to see if your trials have shown a difference between biga and poolish . . . or if it even matters with so very little starter to begin with. I look forward to either theoretical or practical answers. Thanks very much.

[briterian]

Can someone point out the difference between a poolish and a biga?
I think I am using a 'poolish'  I have the camodoli starter - and it's probably about 50%/50% flour/water.  What is the process for constructing a biga? 

Thanks,
b

[Bill/SFNM]

Can someone point out the difference between a poolish and a biga?

Just a quick reminder that this forum's gloassary is a great place to start for questions like this.

[Pete-zza]

fabio,

Whether you use a wetter starter culture (e.g., in "poolish" form, as you call it) or a dryer culture (e.g., in "biga" form), can make a difference in the results. As you may know, Ed Wood, in his book Classic Sourdoughs, discusses the use of both a "liquid" culture and a "sponge" culture. The liquid culture is about 48% flour and 52% water; the sponge culture is about 65% flour and 35% water. Wood has recipes in his book that are devoted to and take advantage of both types of culture consistencies.

Marco (pizzanapoletana) has also talked about starter consistency, along with pH, to achieve certain results, for example, at Reply 399 at http://www.pizzamaking.com/forum/index.php/topic,1053.msg24784/topicseen.html#msg24784. The way that the cultures are fed and the amount used are also factors. My recollection is that Marco uses different cultures for bread dough than for pizza dough and that they have different consistencies (my memory is that the stiffer culture is used for pizza dough). Marco has also previously stated that the poolish and sponge methods are not used for making pizza dough in Naples, but rather for certain desserts (Reply 54 at http://www.pizzamaking.com/forum/index.php/topic,2088.msg24291/topicseen.html#msg24291). So, I took your terminology of "poolish" and "biga" to refer to the consistencies of your starter culture, not their use as preferments in the classical sense as discussed in the Glossary and elsewhere on the forum. If I am correct on this point, you may want to use terms other than "poolish" and "biga" to avoid confusion.

Peter

[fabio]

Pete, you are right, I should be using terms like 'stiff' and 'liquid' instead of 'biga' and 'poolish' in order to be more precise. And so it shall be; when I say liquid starter, it will be referring to a starter that is roughly 50% flour and 50% water (by weight). 'Stiff,' on the other hand, will refer to a more dough-like starter (let's say 62 baker's % hydration).

Your post (and Marco's posts you linked to) make total sense . . . even if you start with very little starter (as I do), the final dough will reflect the acidity of the starter because with little starter it takes longer to proof/ferment/rise, which means the acidity/PH will increase. It also explains why cold-fermented doughs are more sour tasting (not what I'm going for).

As usual, thanks for your rapid and comprehensive answers. I don't know how you manage to get anything else done in a day. Always appreciated.

Now, we've established that to decrease the acidity in the final dough, we need to start with lower acidity in the stiff starter. But what is the process to go from a high-acidity liquid starter to a low-acidity stiff starter? Here are some ideas that I will hopefully get some input on from all of you.

1. Proof the starter at 30C (86F) or so; higher heat should translate to lower lactobacilic activity and higher leaven activity.
2. Refresh the stiff starter often (every 2 hours?)
3. Refresh the stiff starter many times before using it (6-12 times?)

Do those make sense?

Also, now we know that the consistency of the starter makes a difference in the flavor of the dough . . . but how about the structure? I would assume so, since the acidity of a dough has some effect on the gluten structure. Lower acidity would make for a more delicate crust, right?

[Pete-zza]

fabio,

I am not the best one to answer your questions because my use of natural starters tends to be episodic and infrequent, as when I remove a starter culture from the refrigerator after a long period of inactivity to activate it and refresh it to conduct a feasibility experiment, like using it to leaven a cracker-style or deep-dish dough or some other type of dough that is not normally leavened with a natural starter culture. However, I have used both stiff and wetter starter cultures in the context of a Neapolitan style dough, as I noted in the links in this post: http://www.pizzamaking.com/forum/index.php/topic,5484.msg46320.html#msg46320 (Reply 3). Unfortunately, I did not do side by side experiments where the only difference was the consistency of the starter culture and I no doubt switched from one of the two Italian cultures to the other. In my experience, it took longer for the stiffer culture to be refreshed for use, which I attributed to its lower hydration and reduced activity levels. Also, there was a difference in this respect between the two Italian starter cultures. Having the availability of a ThermoKool or like unit no doubt also gives one a much greater control over the fermentation/ripening processes. If I were to be serious about doing these kinds of things, especially on a regular basis, I would use the ThermoKool unit and not rely on having to adapt everything to the prevailing ambient temperatures throughout the year.

Perhaps someone who is currently active in the types of situations you mention can help you with your questions. However, I found the San Francisco Baking Institute article referenced in the above thread to be of interest in refreshing my knowledge on the subject. There is also an informative post at Reply 37 at http://www.pizzamaking.com/forum/index.php/topic,4482.msg38282.html#msg38282.

Peter

[fabio]

Thanks Pete, that's a great amount of information . . . it'll take me a while to digest it all. I have a couple of big proofers I made myself out of styrofoam coolers and light bulbs. I usually use those for stuff other than pizza (ever heard of Panettone and Pandoro? I make about a dozen of each at Christmas). But It would probably be a great idea to start using them for my pizza dough too. I figure I will proof at 25C; should be a good all-year temp.

As a side note, I had some dough left over from yesterday that I put in the fridge last night. I used it today to make a couple of desert pizze. Yesterday there was a good amount of flavor, but I wouldn't have described it as "sour," whereas today it was extremely sour. Good, but not my  thing. I still have the tang in my mouth as I write this! My point though is that the 24hr room-temp proof produced very little sourness (but great flavors), and putting it in the fridge for a while really brought out the sourness. It confirmed to me that I am doing the right thing by doing a 24hr room-temp proof.

Another question: what is the purpose of doing a 2-phase proof (bulk rise and then individual rise)? I know it is vital, but I don't know why.

[Pete-zza]

Another question: what is the purpose of doing a 2-phase proof (bulk rise and then individual rise)? I know it is vital, but I don't know why.

fabio,

To the best of my knowledge, pizzanapoletana (Marco) had never explained why the two step process is needed, only that it is a requirement. I originally thought that the two step process had something to do with what is known as the "mass effect", which says that a large dough mass behaves differently than several smaller masses. At the risk of giving you something more to read and digest, you might want to read the spirited debate that took place on this subject some time ago at the PMQ Think Tank at http://thinktank.pmq.com/viewtopic.php?p=14180#14180.

The above aside, I recently had occasion to exchange PMs with member November on the effects of punching down a dough ball. In my case, I was talking about only a single dough ball. However, I assume that when one divides a large dough mass into several smaller dough balls there is a fair amount of punching down and re-forming that takes place. According to what November told me, when a dough is punched down and reshaped, there is a loss of some of the alcohol in the dough through exposure to air and evaporation, thereby extending the dough's fermentation life. Apparently a specific amount of volume expansion relates directly, albeit nonlinearly, to the amount of alcohol in the dough. Punching down and re-forming the dough also has the effect of redistributing everything. As November pointed out, the yeast will have better access to food, and less of their own waste products or each other to contend with. Re-forming the dough will also have the effect of introducing more air into the dough. While this may increase the void fraction (the volume of the voids in relation to the total volume of dough), the added oxygen to be used for cellular respiration will be minimal (only 20% of the air is oxygen), resulting in only a minimal increase in the yeast cellular respiration (in the order of only a few minutes over a several hour fermentation period). So, the notion of oxygenating the dough through improved aeration to get increased cellular respiration is not a compelling one.

My exchange with November was with respect to a commercially leavened dough but I assume that the principles are pretty much the same for a naturally leavened dough.

Peter

[fabio]

At the risk of giving you something more to read and digest, you might want to read the spirited debate that took place on this subject some time ago at the PMQ Think Tank at http://thinktank.pmq.com/viewtopic.php?p=14180#14180.

lots to read & digest = good

Thanks!

With the utmost of respect to you and November, I think the answer is more simple than that . . . I doubt the Neapolitans of the 16- and 17-hundreds had the knowledge of alcohol in the dough, etc. That said, my own theory is pretty weak: I think maybe it has to do with how the gluten structure is formed. In Italian the phrase for "gluten structure" is "maglia glutinica," which speaks to the interlocking of the gluten (think chain maille). Certainly the interlocking that is happening during proofing is going to be different on a large mass of dough compared to a small mass. But that's probably much too naive. Who knows; I just know that I'm going to keep doing it.

[Pete-zza]

fabio,

No doubt there are physical and structural aspects of the dough as well as biochemical. However, in Reply 36 at http://www.pizzamaking.com/forum/index.php/topic,2951.msg25617.html#msg25617, Marco alluded to (unspecified) factors beyond structural. Also, on several occasions, he has commented on the effects of shortened fermentation times on the digestibility of the final product, for example, as he noted at Reply 4 at http://www.pizzamaking.com/forum/index.php/topic,1942.msg17216/topicseen.html#msg17216 and also at Reply 54 at http://www.pizzamaking.com/forum/index.php/topic,2088.msg24291/topicseen.html#msg24291. So, that facet seems to be material to Marco insofar as the final results are concerned. My recollection also is that Marco said that there is not much rise of the dough during the initial fermentation period (e.g, 12-18 hours) but that there is a rise of the individual dough balls during the second stage, but not double or triple. That has been my experience also for the most part, but whether the principal effects are physical/structural or biochemical, I am not prepared to say.

It is also well known that the heat and moisture developed in a dough during fermentation will be more evenly distributed when it is punched down and divided into individual dough balls. However, I just view this as part of the redistribution process I discussed in my last post.

In the final analysis it may not matter what the reasons are for the two-stage fermentation process, so long as it implemented. However, I like to also know the reasons why. I remember things better when I know how and why things work.

Peter

[Pete-zza]

fabio,

While I was researching another matter, I came upon a post by pieguy at Reply 14 at http://www.pizzamaking.com/forum/index.php/topic,2440.msg21543.html#msg21543 that provides another reason for dividing the original dough mass later rather than earlier--to minimize bubbles in the dough balls.

Peter

[fabio]

Thanks Peter, that is very kind and astute of you!

[scpizza]

The two-stage process redistributes nutrients for the yeast after they have depleted what's immediately around them during the first stage.