Pulsed light technology for fresh-cut produce: A review on mechanism and inactivation kinetics of microbes and enzymes

Consumers are becoming more aware of the benefits of eating healthy foods like fresh-cut produce without compromising the quality of sensory and nutritional aspects. Emerging non-thermal technology like pulsed light (PL) is one of the most potential surface decontamination methods for fresh-cut produce. Unlike conventional methods, PL does not cause unwanted changes in finished products like nutritional losses, color, textural changes, production of off-flavors, etc. Its application is confined to not only surface disinfection but also enzyme inactivation. The death of microbes is due to PL's photochemical and photothermal effects. The photochemical effect is also responsible for enzyme inactivation, and Weibull or log-linear models can explain their inactivation kinetics. Despite several advantages, PL has limitations of less effectiveness in eliminating microorganisms due to low penetration into the tissue of fresh-cut produce, which can be overcome by applying different absorption-enhancing agents to improve absorption capacity. Moreover, in-package treatment can avoid the problem of recontamination of the treated products. This review provides an overview of the mechanisms and kinetics involved in the inactivation of microbes and enzymes in PL treatment. Additionally, this paper reviews the advantages and limitations of utilizing PL technology for shelf-life enhancement of fresh-cut produce and compiles the recent works done to enhance the efficacy of PL treatment. Furthermore, future scope and remedies to solve the existing problems of PL and for commercialization of this technique in the field of fresh produce are discussed.