Phytic acid

by luciano

Phytic acid makes up about 1% of wheat and rye flours, and reduces the bioavailability of calcium, magnesium, and iron by forming complexes with the divalent cations. Phytic acid also inhibits enzymes in the digestive system needed to breakdown starch and protein.1 This explains why some people experience discomfort from eating whole grain wheat products. The sour dough neutralizes the phytic acid and “pre-digestes” the wheat proteins during the fermentation process transforming them into micronutrients that are easy to digest.2


[1] Vaintraub, I. A. & Bulmaga, V. P. (1991). Effect of phytate on the in vitro activity of digestive proteinases. Journal of Agricultural and Food Chemistry 39 (5), 859-861 DOI: 10.1021/jf00005a008

[2] Gänzle, M. G. (2014). Enzymatic and bacterial conversions during sourdough fermentation. Food Microbiology, 37(0), 2-10. doi:


Phytate Degradation during Breadmaking

Moderate decrease of pH by sourdough fermentation is sufficient to reduce phytate content of whole wheat flour through endogenous phytase activity.