The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Sourdough chemistry

marieJ's picture

Sourdough chemistry

I've read much about the sourdough process but have forgotten a some of the terminology.

The process of sourdough fermentation creates an environment in the dough which makes more of the grain's nutrients (vitamins & minerals) available to us.  The acid created assists this.  There is a word that sounds like  'phytates', 'phytytes' - which is involved in this process. Does anyone know what this exact word is?

Its about the acid breaking down a protective componet in the flour chemistry make-up, which in turn allows all the trace elements, vitamins and minerals to become available for our nutrition.  The regular bread making process using commercial yeast does not achieve this due to the absence of lactic/acetic acids.

Any thoughts on what this 'phytate?????' word is?  I did know but I've forgotten and I now have another up & coming baker asking me.  I can't go back to the book as a source of this information because it came from the local library and at this point in time it resides with another borrower.

Any information would be appreciated

Thanks & regards



flournwater's picture

Are you looking for "phytic" acid?  AKA "phytate".

Elagins's picture

not sure of the word, but the process also involves enzymes called amylases that convert complex starches to simple sugars, which end up feeding the yeasts and the aceto- and lactobacilli that make the sour.

temperature affects both the bacteria and the yeast: cooler temps retard the yeast and lacto, which allows the sourdough to develop a more vinegar-like sourness. warmth speeds up the yeast and lacto, resulting in more of the kind of sour you get from yogurt or sour cream.

don't believe I've ever heard a word that sounds like "phytate," but then again, I'm not a biochemist.

Stan Ginsberg

sharonk's picture

This is from the book Nourishing Traditions by Sally Fallon:

"We recommend the use of a variety of whole grains but with an important caveat. Phosphorus in the bran of whole grains, is tied up in a substance called phytic acid. Phytic acid combines with iron, calcum magnesium, copper and zinc in the intestinal tract, blocking their absorption. Whole grains also contain enzyme inhibitors that can interfer with digestion. Traditional societies usually soak or ferment their grains before eating them, processes that neutralize phytates and enzyme inhibitors and, in effect, predegiest grains so that all their nutrients are more available."

This is one of the reasons that sourdough fermentation is said to make the bread more digestible, because the long fermentation time neturalizes the phytic acid.

Hope that helps!



marieJ's picture

Thank you Sharonk, Stan and FlournWater!


This is precisely what I was looking for.  It's been driving me crazy because I've had this knowledge before but couldn't remember the specifics.

Thank you so much!

Cheers and fabulous baking!