Part II — How to Make Sourdough More (or Less) Sour
This second part in our Sourdough Series takes our Country Sourdough Recipe and uses the concepts covered in part one to push that bread in two very different directions. We created a “less sour” loaf with mild, yet complex flavors and an acidity that stayed in the background, as well as a “more sour” loaf that was not only quite tangy but also packed with whole grain flavor.
We applied a slightly different approach to each stage of the bread making process. The loaves detailed below have been pushed fairly close to the limit of what can be accomplished without running into problems with structure or undesirable microbes.
Equipment: Brod & Taylor Sourdough Home and/or Brod & Taylor Folding Proofer & Slow Cooker
Print the tables in this article
Mother Culture — Focus on Healthy Balance
In order to ensure the ongoing health and balance of both yeast and LAB (lactobacilli – acid producers) populations in the seed culture, we kept changes modest: cooler temps, white flour and peak maturity for our “less sour” loaf, versus warmer temps, a little acid-friendly rye flour and a more ripe maturity for the “more sour” bread. We fed our starter twice leading up to the mixing of the levain, but even after just one feed under these conditions, we noticed a difference in the stronger, more acidic aroma of the “more sour” culture.
If there is too little acid in the ongoing culture, undesirable microbes (such as leuconostoc or mold) can multiply and infect the culture. If there is too much acid and an overripe culture, yeast populations are compromised and enzyme activity may get out of hand. To avoid this in our “more sour” loaf, we limited the proportion of whole rye flour to 20% and were careful not to go too far when allowing the culture to mature to a more ripe state.
|More Sour||Less Sour|
|Flour||40g unbleached white flour|
10g whole grain rye flour
|50g unbleached white flour|
|Mature Culture||10g (1:5 ratio of seed to flour)||25g (1:2 ratio of seed to flour)|
|Water||25g (50% hydration)||50g (100% hydration)|
|Temperature||83°F (28°C)||72°F (22°C)|
|Maturity||Use about an hour after peak||Use at peak|
Levain – Get Ready to Encounter Salt
We made significant changes to the levain percentage for these breads. Our standard County Sourdough recipe has 16.6% of the total flour pre-fermented in the levain, our less sour version has a much smaller levain, containing only 10.5% of the total flour, while our more sour bread has a large levain containing 35% of the total flour. The reason for the difference is the presence of salt in the main dough. Salt inhibits the acid producers more than the yeast, which means that once the levain is mixed into the main dough, the ability to produce acid is somewhat diminished. To achieve a “more sour” bread, it’s important to add a larger quantity of acid and acid producers to the main dough.
For the “less sour” loaf, using a small percentage of levain not only limits the amount of acid in the loaf but also slows down fermentation. Slower fermentation allows enzymes in the flour to break down starch into sugar, further limiting the perception of a sour taste.
In addition to getting ready for the addition of salt, we have also incorporated similar maturity, temperature and flour choices as in the mother culture. For the less sour version, we use the levain a little earlier in its cycle than we could for the mother culture — when it is well-risen but has not yet reached its peak. This type of small, less ripe levain has been popularized by Chad Robertson and Ken Forkish in their bread books.
Many bakers’ normal practice is to take part of the levain and use that to perpetuate the ongoing culture. The best way to do that with a small, young levain is to take the portion needed to mix the main dough, then leave the remainder to continue to ripen to full maturity before using it to perpetuate the culture.
More ripe, firm starter for the “more sour” loaf and less ripe, liquid starter for the “less sour” bread
|More Sour||Less Sour|
|Flour||125g unbleached bread flour|
25g whole grain rye flour
|40g unbleached white flour|
|Mature Culture||30g (1:5 ratio of seed to flour)||20g (1:2 ratio of seed to flour)|
|Water||75g (50% hydration)||40g (100% hydration)|
|Temperature||83°F (28°C)||72°F (22°C)|
|Maturity||Use about an hour after peak||Use when well risen but not yet at peak|
Main Dough — Maturity is Key to Controlling Flavor
In considering how much whole grain to put in the overall formula for these breads, we increased the whole grain in the “more sour” loaf from 15% of the total flour up to 20%. For the less sour version, we not only reduced the proportion of non-white flour to 10%, but also switched from whole grain to high-extraction flour and omitted the acid-friendly rye altogether. High-extraction flour can be made easily at home by passing whole wheat flour through a fine strainer to remove the larger bran flakes. As Debra Wink points out, the bran in whole grains buffers acidity and allows the acid producers (LAB) to produce more acid in a more ripe culture. And rye flour produces sugars in the dough that feed the LAB that produce acetic acid, which is more flavorful and noticeable than the other main sourdough acid, lactic acid.
Since the larger levain of the “more sour” loaf carries more enzymes (that degrade protein) into the main dough, we used higher-protein bread flour (instead of AP) for the white flour portion of the loaf and added one extra fold to the bulk fermentation to help ensure good structure.
Larger, more ripe levain for the “more sour” bread and smaller, less ripe levain for the “less sour” loaf.
|More Sour||Less Sour|
|Flour||241g unbleached bread flour|
66g whole wheat flour
|377g unbleached AP flour|
48g high-extraction wheat flour
|Water||243g (69% hydration)||278g (69% hydration)|
|Salt||9g (1.8% of flour weight)||9g (1.8% of flour weight)|
|First Fermentation Temperature||85°F (29°C)||74°F (23°C)|
|Maturity||Rise until tripled||Rise until doubled|
|Proof Temperature||85°F (29°C)||74°F (23°C)|
Ready to begin your own exploration of sourdough acidity? We have generally found that the most effective factors for controlling acidity in sourdough are-
1) sourdough starter maturity (the degree of ripeness)
2) the choice of temperature for the starter, levain (if using one), and the dough (warmer for more acid, cooler for less)
3) the choice of flours for the starter, levain (if using one), and the dough (whiter for less acid, more whole grain, particularly rye, for acidity)
The key to making changes is to keep them modest and use only one or two at a time, then assess how they affect other aspects of the dough before deciding which to jettison and which to embrace.
Leave a comment
I followed the more sour formula but at 83 degrees F. my dough is over fermented so fast even folding every 20 minutes in stead of 30 minutes. I have not been able to get good oven spring. How long a bulk ferment is normal at 83 degrees? Should I eliminate a fold or two. I normally try to fold 4 times, but after 3 it is too late! Any suggestions? Mark
Mark – There are no hard and fast rules when it comes to sourdough fermentation. Much of it is observing your dough and adjusting accordingly to get the desired results. That said, we can suggest a few adjustments. A good starting place is to lower the proofing temperature by a few degrees. You can also try shortening the bulk fermentation time (and shortening times between folds if necessary). Let us know if you are still having over-proofing issues.
question about “Part II — How to Make Sourdough More (or Less) Sour” What kind of wheat flour is “high-extraction wheat flour”? What is “Rise Temperature”? is the same as bulk/first fermentation? “The most effective factors for controlling acidity in sourdough are-2) the choice of temperature (warmer for more acid, cooler for less)” are these factors about the starter or the dough? You use the term “sourdough”, but sounded like you are talking about the factors of the starter since the first factor is “the degree of ripeness”. It would be good if you could include the water temperature in the information as well. There are a lot of beginners out there, including me. much appreciated all the informations.
Austin – High-extraction wheat flour is whole-grain wheat flour with some of the bran sifted out. It is not quite whole wheat flour- you can think of it as a cross between white flour and whole wheat flour. If you can’t find any to purchase, high-extraction flour can be made easily at home by passing whole wheat flour through a fine strainer to remove the larger bran flakes. Others will simply add a small percentage of whole wheat flour to their white flour. Rise temperature- we are referring to bulk fermentation/first fermentation. The first factor, maturity, we are referring to is the starter only. However, the longer a dough ferments, the more sour it will become. Temperature and choice of flour can be applied to both starter and dough. We did not include water temperature, but we did include fermenting/proofing temperatures. Ideally, you use a water temperature to allow your starter and/or dough to be at the desired fermentation temperature. So, your water should be around the same temperature as the temperatures listed in the chart. Thank you for taking the time to provide feedback! We made a few changes to the language to clarify the information.