Is Sourdough Healthier Than Yeast Breads?
Short answer: Yes.
Compared to yeast breads or breads leavened exclusively with commercial yeast, sourdough is fermented for a longer period, anywhere from several hours to a few days. During this process, the sourdough bacteria (lactobacilli) produce lactic acid, which raises the dough’s acidity and activates various enzymes (biochemical catalysts) in wheat and other related grains. Under the correct conditions, this effect results in the following 4 health benefits:
1. Less Phytic Acid, More Minerals
Whole wheat breads are excellent sources of minerals. However, they also contain phytic acid which binds to important minerals and prohibits mineral absorption. One of the few ways to break down phytic acid and increase mineral availability in whole wheat breads is to acidify the dough.
2. Degradation of Gluten
Gluten consists of two proteins: glutenin and gliaden. Both proteins are found in wheat and other related grains such as barley and rye. Moreover, studies have shown that gluten is degraded when the dough is acidified through sourdough fermentation. Consequently, this opens up the possibility of safer breads for people with gluten sensitivity.
3. Improved Blood Sugar and Insulin Response
According to a few studies, the buildup of lactic acid produced by sourdough bacteria may delay starch digestibility, which results in lower glycemic (blood sugar / glucose) and insulin responses. The reduction of simple sugars during sourdough fermentation may also contribute to such effects. Thus, sourdough breads may be beneficial to diabetics.
4. Improved Shelf Life
Sourdough has the potential to improve the shelf life of breads, thereby limiting or omitting the use of chemical preservatives. Studies have also reported that higher acidity in breads may hinder staling (starch retrogradation) and inhibit the growth of rope spoilage bacteria. In addition to that, sourdough bacteria have been observed to generate compounds to ward off mold.
Summary: compared to yeast breads, sourdough breads contain less phytic acid, has better mineral absorption properties, has potential health benefits to gluten sensitive individuals and diabetics, and requires less or no chemical preservatives.
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Author: Zita (bakingbadly)
Published: January 29th, 2014
Last Modified: July 20th, 2014