November, do you have any insights on the optimal rise temperature (for flavor) for the Ischia and/or Camaldoli starters using Caputo 00 Pizzeria?
I don't have anything specific to report about optimal temperatures for starters. I've always handled my starters (when I use them, which is very rare) the same way as my dough with regard to temperature. With the finer granularity of 00 flour, less work is needed by the enzymes to convert the starch to simple sugars, so you can get away with lower temperatures using 00 flour relative to other flours. I've spent a lot more time with preferments than what are generally referred to as starters, as I'm only performing the extra work for better flavor. I don't like to catch wild yeast, or keep the same dough around for the purpose of starting subsequent batches.
One way I recently tried to improve flavor is by attempting to increase lactic acid production. I did this by incubating my starter through several washings at 33C. According to the temperature graphs in Ganzle, et. al. this should shift the population in favor of L. Sanfranciscensis over C. Milleri. Indeed the resultant culture smelled non-yeasty and dull-sour.
With respect to one bacteria over another, that's fine. However, with respect to bacteria over yeast, depending on how much yeast you have in your starter, that's not usually the case. As has been mentioned several times before, bacteria can thrive at temperatures below the comfort zone for yeast, so keeping the dough cool (as in 5 C) accomplishes your goal in the long run. That's why food can still spoil even if kept in the refrigerator. You may want to keep your yeast away from your starter when you have the starter at 33 C, or use extremely miniscule amounts. The more acetic acid that is produced by the yeast, the less your bacteria will be able to function.
Unfortunately dough made with the culture, rising at 25C, showed no improvement in taste and actually lacked flavor. I wonder if the interdependencies between the two organisms, such as the malic acid link you mention, kept the LAB from doing anything in excess of the proportion of yeast and thus defeated my skewing of the population.
Lactic acid contributes, by most people's standards, a better flavor, but acetic acid is by far a stronger acid in terms of palate sensitivity. It's like the salt of acids. A little bit goes a long way to enhance flavor. By lowering your temperature to 25 C, you created conditions where comparatively speaking, less acetic acid is produced. At the same time, less malic acid would be produced also, but keep in mind that yeast produces very little malic acid compared to acetic acid. Since each person has their own subjective flavor preference, you apparently found a region near 30 C, with whatever amount of yeast you used, that produces the mix of acids (and related organic compounds) that are favorable to you.
I am also vexed by conflicting information in regards to the favorability of lactic vs. acetic acid for improved flavor. Some information says lactic acid is preferable in that its non-volatility means it doesn't evaporate at baking; plus the lactic taste is more appealing than the acetic vinegary taste. Other information points out the tongue is not where the complex tastes are registered; it's actually the nose, and thus the volatile compounds like acetic acid are preferable over lactic acid. What are your thoughts?
First of all, lactic acid and acetic acid are both carboxylic acids with similar boiling points, so the evaporation at baking will also be similar, with acetic having only a slightly higher evaporation rate. Due to acetic acid's smaller molecular weight, it is more penetrating and aromatic than lactic. That's one of the reasons why our sensitivity is higher with acetic. It's been well studied and documented that flavor is approximately half odor and half taste. There are a lot of biochemical registers that are set off as a result of smelling your food. It has long been believed that people ingest more when their food is cold, because the lower temperature prevents certain aromatic compounds from evaporating from the food, and triggering a response in the brain telling it how much food they've even. Refrigeration was an invention of man, so our bodies aren't designed to deal with the consumption of food at temperatures less than around 20 C. The effect is minimal for some people, but it's there at some level for everybody. That's why a lot of people report being able to eat a whole box of cereal (with cold milk) before getting full. There are few aromatic compounds in cereal to begin with, and eating it with cold milk exaggerates the effect. So, I said that to say this, acetic acid does register with the senses (gustation and olfaction) more than lactic acid, but more so with gustation (taste).
I get around the whole idea of trying to get bacteria to produce lactic acid for me by using food products like soy butter, or my favorite so far, "Better Than Cream Cheese" by Tofutti. The lactic acid they add to soy products like this is produced by bacteria simply fed cane sugar. Since these products lack lactose or other milk solids, they don't taste exactly like dairy, but instead have a generic cheesy/buttery flavor which compliments pizza dough very well. It's essentially what you're looking for but without all the work. The primary fat is soybean oil, so I usually use about 20-30g soy cream cheese with 7-10g of olive oil or rice bran oil for a total of 10-15g total oil in a 900-1000g dough batch. Because of this process, I rarely use preferments anymore. Some may consider that cheating, but by some standards, so is letting someone else grow your wheat and mill it for you too.