Optimization of enzymatic hydrolysis of pigeon pea for cooking quality of dhal.

Cooking quality of dehusked splits is influenced by the dehulling method, in particular, by the pre-milling treatments. The effects of four enzymatic hydrolysis parameters, i.e., enzyme concentration (2-60 mg/100 g dry matter), incubation time (3-15 h), incubation temperature (40-60°C) and tempering water pH (4.0-6.0) on cooking time of pigeon pea dhal were optimized using response surface methodology. Three kinds of enzymes, i.e., xylanase, pectinase, and cellulas were used in combination for enzymatic pre-treatment. A quadratic model satisfactorily described the dehulling efficiency with high value for the coefficient of determination R2 (0.9062). It predicted a minimum cooking time of 21.91 min at enzyme concentration of 37.8 mg/100 g dry matter, incubation time 8.69 min, incubation temperature 48.5°C and pH 5.49 of tempering water. Cooking time at optimum condition was observed to be 21.50 min and the predicted values of cooking time showed 2.19% deviation from the experimental values. Results of the study revealed that cooking time of enzyme treated dhal could be decreased by 19.77% compared to the oil treated dhal. [ABSTRACT FROM AUTHOR]