Pulsed Light Technology for the Fruit and Vegetable Processing Industry

Pulsed light (PL) derived applications are among the emerging physical technologies that are extensively investigated as a non-thermal gentle alternative to thermal pasteurization for killing typical pathogenic and spoilage microorganisms without critically compromising the quality of the fresh produce. PL treatment, consisting of short, high-energy, broad-spectrum light pulses has been proven effective in reducing microbial load on fruits, vegetables, and juices, inhibiting some endogenous enzymes in plant tissue, and positive metabolic alterations in fresh fruit and vegetables during storage, etc. Various wavelengths of light were reported to enhance the nutraceutical bioactive compounds, such as vitamins, carotenoids, and phenolic compounds in fresh fruits and vegetables. PL disinfection minimizes the overall quality damage to food products compared to conventional thermal treatment. PL surface disinfection of organic or food-related inorganic sources has the advantage of no harmful residue compared to chemical disinfectant. High initial investment costs, maintenance for PL equipment, and difficulty in standardizing process parameters for each product are of concern for commercial applications. Despite intense research activities, in some cases, the inactivation performance of PL on food surface-related microorganisms is still below the FDA-recommended 5-log pathogen reduction standards. In order to successfully tackle efficiency and safety issues for commercial applications, more research on PL within hurdle applications is expected to be conducted in the future.