Pulsed Light Decontamination of Red Chilies (Capsicum annuum var. longum)

Abstract

The impact of pulsed light treatment (PLT) on natural microbiota and inoculated microbes such as Salmonella Typhimurium, Bacillus cereus, and Aspergillus flavus on red chilies was investigated. Sequential drying did not completely inactivate the aerobic mesophiles and yeast and mold count. Hence, PLT (0.53–2.59 J cm⁻²) was employed as a decontamination technology on red chilies. PLT resulted in 8 log reduction of inoculated microorganisms on chilies at 2.59 J cm⁻². The microbial inactivation kinetics followed Weibull distribution (R² > 0.97) with β value of 1.1, 1.2, and 1.5 for S. Typhimurium, B. cereus, and A. flavus, respectively. Changes in structure and composition of cell components were identified by SEM and FTIR analysis. After PLT, phenolics, antioxidants, flavonoids, and capsaicinoids were better retained but a significant change in ascorbic acid and carotenoid's content was observed. Hence, PL can be a potential technology for decontamination of fresh and dried chilies along with maximum retention of bioactives.