Optimization of blanching treatments of green chilli

Abstract

Blanching is a thermal treatment that is usually carried out prior to food processes such as drying, freezing, and canning. It is an essential unit operation to preserve the product quality attributes during the long-term storage because it inactivates the enzymes and reduces microbial load. In this study, sample of green chilli was used for blanching treatment to increase the shelf life with acceptable quality attributes. The experiments were conducted according to Central Composite Rotatable Design (CCRD). The blanching treatment conditions were optimized by using response surface methodology. The samples of green chilli were treated with concentration of potassium metabisulphite (0.5-1.5%) at blanching time of 0.5 to 2.5 min in boiling water before drying. The drying of green chilli was carried out at 60 °C for all samples. The response variables taken were rehydration ratio and visual color. The optimum values of concentration of potassium metabisulphite and blanching time were found to be 0.7 % and 1.5 min respectively at a desirability value of 0.60. The optimized values of pre-treatment conditions could be utilized for dehydration of green chilli to get better quality of dehydrated green chilli.