Effect of fermentation on HCl-extractability of minerals from rice-defatted soy flour blend

Buttermilk fermentation at 25, 30 and 35°C for 12, 18 and 24 h brought about a significant increase in non-phytate and HCl-extractable phosphorus with a corresponding decline in phytate phosphorus of a rice-defatted soy flour blend mixed in a 50 : 50 proportion. The HCl-extractabilities of calcium, iron, zinc, copper and manganese from the rice-defatted soy flour blend also improved. Higher HCl-extractability of minerals may be partly ascribed to the decreased content of phytic acid, as a significant negative correlation between the phytic acid and HCl-extractability of dietary essential minerals was obtained.