In one of his books, Peter Barnes says that the difference in taste between American sourdough and French levain is that sourdough is more sour whereas levain has a milder, “buttery” taste; and he says that this difference is caused by the presence of different bacteria. Sourdough is strong in acidophilus, the bacteria responsible for the souring of milk when making yogurt. This bacterium produces acetic acid, which is the acid found in vinegar, and the taste tends to be fairly strong. French levain, on the other hand, is strong in the bacteria that produces lactic acid, a bacterium found also in buttermilk culture. Lactic acid produces less of the sour taste and is responsible for the buttery flavor of French country boules.
Barnes goes on to say that the way you refresh your starter and the temperature at which you keep it will influence which bacteria predominates. He says that acidophilus likes a soupier starter and a warmer termperature; whereas the bacteria that produce lactic acid like a more dough-like starter and lower termperatures.
I prefer the milder French style starter for bread, but like the sour one for things like pancakes and waffles. I am going to try building a starter using raisins for the yeast, but then adding a bit of buttermilk to capture those bacteria and see if I can get a starter that produces a milder flavor.
Interesting. My starter is maybe on the liquid side, can pour, like waffle batter. But I keep it in the fridge between bakes. Pull it out only as long as i need to get it floating. Maybe 4-8 hrs depending on space between bakes. Unlike some people though, I do pull the whole thing out, rather than separate out a small amount and put the rest back into the fridge immediately.
My bread is hint-o-sour. I can make it more sour by retarding it in the fridge during either or both of the proofing phases, but it doesn’t get crazy sour ever.
I want to correct the author I referenced. It was Peter Reinhardt, not Peter Barnes. The book in which he talks about lactic acid producing bacteria versus the ones that produce acetic acid is either The Baker’s Apprentice or Crust and Crumb. My books are in storage so I can’t look it up right now.
My husband has that book - a past christmas present that resulted in a few breads the following January. I took up bread two years later and he is oh-so exasperated with me that I haven’t read the book, rather rely on the Internet. Let me know if there is something you want me to look up - confirm the acetic vs lactic?
Thanks, Fermentada, that is really helpful. Clearly, I got things reversed. I thought it was the firmer starter that produced the Lactic bacteria.
I’ve been living on a boat for the past seven years and recently moved back ashore; so my breadmaking has been limited to flatbreads for a long time. I am enjoying getting my chops back. My aim is to reproduce the Jewish rye that I used to get at a deli on my commute through Newton, Massachusetts. The crumb was soft and light, while still being sturdy and elastic; and the crust was crackling crisp without being at all tough. I’d just get an egg salad sandwich so I could really enjoy the bread. I can’t find rye bread like that anywhere in the Boston area any more. It’s all either overpowered with caraway seed or else laden with cinammon and dried fruit — I wander around, muttering, “Man does not live by toast and cream cheese alone!”
Wow - living on a boat. I can see how that might not be conducive to constant baking. I wish you all the best in finding or creating that rye bread.
I have a few nostalgia food quests myself. I was buying kimchi at Asian grocery stores and Whole Foods, and being disappointed by every jar, hoping to match a memory of good kimchi at a restaurant 15+ years ago. Finally, I watched a Korean YouTube cooking star make it on a video, copied her recipe and achieved my goal.
Bread, though, is so tricky. It’s never just the recipe. The timing, execution, and environment matter a lot too. A friend of mine drives farther to a Whole Foods for the bread from their in-house bakery, because the same recipe/same bread from the closer one is just not as good.
There is no difference between the bacteria that produce lactic acid and acetic acid. It’s the same bacteria, lactobacillus sanfranciscensis, but they produce the different acids based on conditions. The type of acid depends on the type of metabolism taking place. Lower hydration and temps will produce acetic acid, and higher hydration and temps will produce lactic acid. The following articles written by Debra Wink, although quite technical in nature, go into great detail about the various processes that happen during fermentation and starter preparation. Also the book Bread Science goes into the details of the chemistry of sourdough and yeasted breads. https://www.amazon.com/Bread-Science-Chemistry-Craft-Making/dp/0977806804
Thanks for sharing the articles. The link to the super-biochem one (10375) is neat…and above my head, but about maybe 7-8 comments down, the author summarizes the findings - yay. Thanks again.
Here’s a quote that maybe is about the difficulty you’ve had in finding the rye you remember:
“Jewish rye bread, like the bagel, is in a constant state of peril, with ever fewer traditional bakeries making it. One bulwark is Orwasher’s in Manhattan, where 10-pound loaves of sissel rye are baked daily, just as they have been since 1916, when the bakery was founded in Yorkville. The owner, Keith Cohen, calls it a “community loaf”; customers can buy as much or as little as they need. Orwasher’s still starts its rye from a traditional biga, a live sourdough culture, instead of the yeast and other additives most commercial bakeries use. On weekends, Orwasher’s makes an old-school kornbroyt, a slow-risen, rougher-textured bread with more of the whole rye grain.”
Thanks for the article on rye bread and glad you liked the links. I’ve also found that the comments can be very informative!
I’ve not been doing much with rye or even seeking anything out. Perhaps that comment was addressed to someone else? At any rate, I’ve recently had some requests from customers for rye bread so I’m going to start working with it more. I do only sourdough so the recipes/formulas listed do not hold a lot of interest for me. I will experiment with changing the yeasted formulas to SD. At this point my basic rye loaf is 50% rye, 10% other whole grains, and the rest bread flour. I also add 6 grams of caraway seed to the dough, which unfortunately, some folks do not care for. Personally, I love caraway in bread (as well as in sauerkraut I make). That much rye makes for a super sticky dough, but it does come around after a few hours of fermentation to be not quite so sticky.
I think there are, actually, more kinds of lactobacillus than just lactobacillus sanfranciscensis. According to Debra Wink (in the first article that Dean references), there are several kinds of bacillus that produce lactic acid as well as many different kinds of lactobacilli, some producing lactic acid and some acetic acid,
“Lactic acid bacteria common to sourdoughs include members of Leuconostoc, Pediococcus, Weissella and other genera. But by far, the most prevalent species belong to the very large and diverse genus, Lactobacillus. Based upon how they ferment sugars, lactic acid bacteria can be sorted into three categories.”
You are correct that there are numerous yeasts and bacterium in grains that go into the making of a SD culture. However, in a Type I SD culture, one that is fed once or twice daily, there is one strain of LAB and between 1-4 strains of yeast. This is because once an environment is established and maintained, it doesn’t not allow for the proliferation of other strains. Other strains are constantly being introduced every time the culture is fed, but when the culture is strong, “alien” strains are not allowed to grow to significant levels. This is why storing in a refrigerator can cause “off” flavors to develop. If you can access the following study in its entirety, it talks about the various types of SD culture and the strains present in each. It has to do with homofermentative and heterofermentataive bacteria and whether they are obligate or facultative. I do have the article but am not allowed to share it for copyright reasons. http://www.sciencedirect.com/science/article/pii/S092422440400192X
If you use the tiniest bit of starter to make a leaven, it doesn’t really matter. It is always delicious. Never overly sour. Do not use too much starter and do a very long bulk fermentation, whether in the fridge or not. This is the key.
That does tend to work. However LAB activity increases a lot at higher fermentation temperatures of 28C - 30C. So by fermenting the dough and the natural leaven at lower temperatures 24C to 26C there will be more yeast and less LABs. The longer the preferment is kept between feeds the more LABS will develop. Storing the leaven in the fridge reduces this.
My natural leaven breads (Sourdough to some) are never sour. Which is how I prefer them. This is attained by temperature management. I mostly use the leaven at 20% measured by its flour weight.
Great post.
Acetic Acid Bacteria (AAB) are little studied in bread. The AAB has very complex metabolic interactions with the by products of both yeast and LAB fermentation.
One study found that they increased the flavour profile (not referring to vinegar flavours here) and gave a softer mouthfeel with greater loaf volume. In excess, yes, they and vinegars from heterofermentative LABS do give a vinegar flavours I find unwelcome.
LAB acidity is not a geographic phenomenon. It is largely dependent on the temperature at which the natural leaven and the dough are fermented. LABS activity is much higher than that of yeast above 28C. This will give more acidic notes. Keeping the fermentation down to 24C - 26C will give less acidic bread.
