Kinetics of Tannin Reduction in Soaked and Unsoaked Velvet Beans Treated by Microwave Treatment

Abstract

The effect of microwave treatment on the kinetics of tannin reduction in black and white colored velvet bean (soaked and unsoaked) was evaluated. The objective of this study was to determine the association level and the kinetics of tannin reduction in velvet beans after being treated with microwave treatment in order to find the appropriate time treatment useful for poultry health. Tannin content reduction rate was nicely fitted by linear regression analysis with association value (r) ranging from 0.96-0.98. Linear regression analysis suggests a zero-ordered kinetics which means that the decline rate of tannins after exposure to microwave treatment is independent of the initial tannin concentration.  In both colored velvet bean (black and white), the tannin reduction rate of unsoaked seeds was lower than that of soaked seeds. According to literature findings regarding the positive role of tannins level in poultry, it can be concluded from this study that the exposure of velvet bean to microwave treatment for more than 12 minutes may eliminate the positive effect of tannin on poultry.