Process optimization to increase resistant starch in vermicelli prepared from mung bean and cowpea starch

Abstract

This research developed a process to increase the resistant starch (RS) content in vermicelli prepared from a mixture of cowpea and mung bean starch. The physicochemical and functional properties of mung bean starch (M) and cowpea starch (C) were evaluated at different ratios to determine the optimum starch mixture for the vermicelli. A response surface method (RSM) with central composite design (CCD) was used to determine the effect of incubation times at 4°C, and freezing times at -13°Con the RS content in the vermicelli. The results suggested that the starch mixture of M:C (2.5:2.5) was the most suitable for preparing vermicelli. The optimum condition to improve the RS content of the vermicelli using RSM was incubation of the fresh noodles at 4°C for 1h 30 min, followed by freezing at -13°C for 21 h (R2 = 0.95). Under these conditions the RS content of the uncooked noodles increased to 29.20%, compared with vermicelli prepared without incubation (20%) and by the reference method (23.93%).The cooking and texture qualities of the vermicelli were also evaluated. The optimization of RS content had no effect on the cooking and texture quality of the noodles, and statistical tests indicated that the RSM model showed good fit and was suitable for application in high resistant starch vermicelli production.