Optimization of Disinfection Treatment for Shelf Life Extension of Fresh Cut Salad Vegetables

Abstract

In the present study, disinfectant pre-treatment conditions were optimized for Fresh cut salad vegetables after evaluating bactericidal efficacy of the five different disinfectants viz. Sodium hypochlorite, potassium metabisulfite, citric acid, acetic acid and benzoic acid. Sodium hypochlorite @ 100ppm was selected for disinfectant pretreatment of fresh cut vegetables viz. cucumber, carrot and tomato through physicochemical and microbial analysis. Optimization of pre-treatment conditions viz. temperature, pH and contact time was statistically designed and analyzed using response surface methodology. Numerical optimization of results revealed a temperature of 6.5, 10.0 and 6.5°C; pH 6.0, 7.0 and 7.0; contact time 23.0, 8.0 and 30.0 minutes was found to be optimized for fresh cut cucumber, carrot and tomato disinfectant pretreatment with a desirability level of 94, 94 and 92%, respectively. Shelf life analysis of pre-treated (under optimized conditions) and untreated fresh cut vegetables stored under refrigeration conditions (5-7°C) revealed enhancement in shelf life of treated fresh cut vegetables from 6, 9 and 6 days to 9, 12 and 9 days of fresh cut cucumber, carrot and tomato, respectively. During shelf life period, all physicochemical parameters of pre-treated fresh cut vegetables differed non-significantly along with microbial load under acceptable limits and a good sensory score.