Effect of pulsed light technology on microbial quality, enzyme activity and physicochemical attributes of green chilies (Capsicum annuum var. longum) at different levels of water activity

The shelf life of green chillies is very low due to high-water activity (aw = 0.90 ± 0.01). Balancing aw and moisture content is crucial for maintaining freshness, quality and extending shelf life of green chillies. To attain microbial and biochemical stability, the aw should be reduced to 0.6 and 0.3, respectively. Hence, a controlled drying process was introduced. The 0.6 aw (62 ℃/360 min + 35 ℃/60 min) and 0.3 aw (75 ℃/600 min + 40 ℃/240 min) green chillies improved bioactives retention, colour and texture; but could not completely prevent the growth of microorganisms. Therefore, post-drying, a decontamination process i.e., pulsed light (PL) treatment of 0.53 to 2.59 Jcm−2 (1.7–2.1 kV/120–360 s) was employed. Along with microbial decontamination and enzyme inactivation, PL preserved better physicochemical characteristics in 0.6 and 0.3 aw than 0.9 (fresh) green chillies. While, there is 89.8