Solid-State Fermentation Reduces Phytic Acid Level, Improves the Profile of Myo-Inositol Phosphates and Enhances the Availability of Selected Minerals in Flaxseed Oil Cake.

Flaxseed oil cake was subjected to fermentation with Rhizopus oligosporus (DSM 1964 and ATCC 64063), and the phytate (InsP₆) content, myo-inositol phosphate profile and in vitro bioavailability of essential minerals were studied. Flaxseed oil cake had a phytate mass frac tion of 13.9 mg/g. A 96-hour fermentation of flaxseed oil cake by R. oligo sporus DSM 1964 and R. oligosporus ATCC 64063 decreased the InsP₆ content by 48 and 33 %, respectively. The strains had different phytate-degrading activities: fermentation of flaxseed oil cake with R. oligosporus DSM 1964 was more advantageous, yielding InsP_3-5 as a predominating myo-inositol compound, while fermentation with R. oligosporus ATCC 64603 produced predominantly InsP_5-6. Solid-state fermentation of flaxseed o il cake enhanced in vitro bioavailability of calcium by 14, magnesium by 3.3 and phosphorus by 2-4 %. [ABSTRACT FROM AUTHOR]