Degradation of Phytic Acid and Soy Protein in Soy Meal via Co‐fermentation of Aspergillusoryzae and Aspergillusficuum

Abstract

AbstractThe usage of soy meal (SM) as a protein source for young monogastric animals is limited by the presence of antinutritional factors. To address this problem, fermentation was applied to simultaneously degrade phytic acid and soy protein in SM. Aspergillusoryzae (ATCC 9362) and Aspergillusficuum (ATCC 66876), sources of protease and thermostable phytase, respectively, were co‐fermented using a two‐stage temperature protocol: 36.5 °C (0–28 h), then 50 °C (28–40 h). The two‐stage co‐fermentation approach achieved a 17 % increase of phytic acid degradation compared to A. oryzae fermentation and 72 % increase in protein degree of hydrolysis (DH) compared to A. ficuum fermentation. The two‐stage temperature fermentation produced a 27 % increase in phytic acid degradation and 90 % increase in DH compared to a single‐stage fermentation. The fermented SM with reduced levels of antinutritional factors would serve as high quality feedstuff.