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

Robert Duliński1*small orcid_display_4pp, Bożena Stodolak1small orcid_display_4pp, Łukasz Byczyński1small orcid_display_4pp, Aleksander Poreda2small orcid_display_4pp, Anna Starzyńska-
-Janiszewska1small orcid_display_4pp and Krzysztof Żyła1small orcid_display_4pp

1Department of Food Biotechnology, Faculty of Food Technology, University of Agriculture in Krakow, ul. Balicka 122,
  PL-30-149 Kraków, Poland
2Department of Fermentation Technology and Technical Microbiology, Faculty of Food Technology, University of
  Agriculture in Krakow, ul. Balicka 122, PL-30-149 Kraków, Poland

Article history:
Received: September 8, 2016
Accepted: May 4, 2017

Key words:
flaxseed oil cake, solid-state fermentation, phytates, myo-inositol phosphates, mineral availability

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 fraction of 13.9 mg/g. A 96-hour fermentation of flaxseed oil cake by R. oligosporus 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 InsP3-5 as a predominating myo-inositol compound, while fermentation with R. oligosporus ATCC 64603 produced predominantly InsP5-6. Solid-state fermentation of flaxseed oil cake enhanced in vitro bioavailability of calcium by 14, magnesium by 3.3 and phosphorus by 2–4 %.

*Corresponding author:  email3