In this experiment we sought to explore the characteristics of sprouted flour with some real-world baking. We made two NY Deli Rye Breads, one with regular rye flour and one with sprouted rye flour and compared their fermentation speed, oven spring, crumb, and flavor. Sprouted flours are said to ferment faster, taste sweeter, and be at risk for gluten breakdown in the dough. Sprouting activates enzymes in the grain that make nutrients more available for digestion and also convert starch to sugar — which is what the yeast and/or lactobacillus microbes consume during fermentation. This enzymatic activity can also break down gluten, especially if the fermentation process is long, making a flatter, more gummy bread.
The quick summary of our results is that in this dough formula of 35% regular rye vs sprouted rye and in this process of a 5-hour bulk fermentation to 80% expansion and a 14-hour refrigerated final proof; the fermentation speed seemed to be the same, the regular rye had more oven spring and more sour flavor, and the sprouted rye crumb was more open and also more gummy. All the sprouted grain facts above were confirmed except for fermentation speed, though given the more open crumb of the sprouted rye, perhaps there was more fermentation, just without extra expansion of the dough because of the slightly weaker gluten situation.
It should be noted again that these results apply to this test bake using sprouted rye flour in this quantity with this process. In fact, one of Breadtopia’s most airy bread recipes, our Sprouted Wheat Ciabatta, uses sprouted hard red spring wheat for about 14% of the total flour. Additionally, our tall Sprouted Wheat Sourdough Bread is made entirely of bolted sprouted hard red spring wheat, and our feathery-crumb Honey Whey Sourdough Bread with Sprouted Spelt has 15% sprouted spelt flour.
Here is the formula we used for the two test breads. It has more rye flour and fewer caraway seeds compared with the original recipe linked to above.
330 grams bread flour (2 1/2 cups)
200 grams rye whole grain flour OR sprouted rye whole grain flour (1 1/2 cups)
395 grams water (1 2/3 cups)
100 grams sourdough starter (1/3 cup)
21 grams honey (1 Tbsp)
11 grams salt (2 tsp)
1 gram caraway seeds (1 tsp)
Process and Results
Surprisingly the two doughs seemed to ferment at the same speed, reaching about 80% expansion in 5 hours in a warm summer kitchen. Once the doughs were shaped, they went straight into the refrigerator for 14 hours. They looked similar the next morning and were baked at the same time directly from the refrigerator.
- Bulk, 5 hours
- Final Proof, 14 hours refrigeration
The regular rye bread had more oven spring than the sprouted rye bread, indicating that indeed some gluten breakdown had occurred. Given how little gluten rye flour has to begin with, this seems to indicate the gluten breakdown didn’t only happen to the rye grain during the sprouting process but also carried forward into the dough. The doughs were equally firm when turned out of the proofing baskets to score, and neither splayed after being scored so the outward spread of the sprouted dough seemed to have occurred during baking.
Even though the doughs expanded the same amount during the bulk fermentation and final proof, the crumb of the sprouted rye bread (right) was more open, suggesting perhaps it did have more fermentation activity. This can be seen in the photos below and at the top of this article. The sprouted rye crumb was also more gummy/shaggy than the regular rye bread (left). These loaves were cut within hours of baking and did have cleaner cuts the next day.
In terms of flavor, three blind taste testers noted that the sprouted rye bread was less sour than the regular rye bread. This makes sense given that sweetness can offset sourness (and bitterness). Two of the taste testers liked both breads equally, and one preferred the more sour regular rye bread.
Conclusions
As noted above, these results apply to this dough formula and process. Especially of note is the fact that rye flour already has high enzymatic activity even before sprouting. In this test, the sprouted rye bread was flatter, had a more open and gummy crumb, and tasted less sour. It is possible the more open crumb of the sprouted rye bread came from greater fermentation activity despite the doughs having the same apparent expansion in the buckets and bannetons.
Notes on Rye Grain
Rye grain is a member of the Triticeae tribe that also includes wheat and barley. It’s tolerant of cold weather and poor soil and has been cultivated for millenia throughout Russia and Northern and Eastern Europe. The flavor of rye is distinctively earthy and slightly malty. Even unsprouted, rye flour has a relatively high amount of amylase enzymes (responsible for breaking down starch into sugar) compared with wheat flour. Unchecked, amylase activity can make the crumb of a bread gummy. Amylase activity slows down in an acidic environment, which is why rye benefits from being fermented with sourdough, which is more acidic than yeast. Rye also has high levels of complex sugars called pentosans which absorb water. Pentosans in rye make the dough sticky but also contribute to creating its structure. Used as the only flour in bread, rye makes a dark and dense crumb that needs to set for at least 24 hours after baking in order to not be gummy. Whole rye breads last for weeks and can also be sliced thin and toasted into crisps. Breads that combine rye and wheat flours are more airy and still resist staling, and many people say they can taste the presence of rye flour in a bread when it’s as little as 5% of the total flour.