Optimization of steam blanching treatment for minimal processing of French beans

Abstract

Effect of blanching treatments on peroxidase (POD) enzyme activity, protein content, L a b values, moisture and ash content in French beans were studied. The experiment was planned as per CCRD RSM technique. The process variables were blanching time and length of French beans at steam pressure of 1.15kg/cm². Forced convection steam blancher was used for blanching French bean. It was found that blanching was adequate at length of French bean 5mm,10mm and blanching time 30sec, 60 sec,120 sec respectively with 95% peroxidase enzyme inactivation, where as it contained 12.10 to 17.24 protein content, 13.95 to 28.34 L, -3.43 to 2.27 a, 03.06 to -18.03 b value. Steam blanching has significant effect on color retention fresh alike, than unblanched dehydrated French bean.