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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. [ABSTRACT FROM AUTHOR]

This study investigated the impact of pulsed light (PL) applied at a fluence of 4–12 J cm−2 (complying with U.S. Food and Drug Administration standards) on fresh‐cut watermelon, focusing on its efficacy in inactivating various food‐borne pathogenic gram‐positive (Escherichia coli and Staphylococcus aureus) and gram‐negative (Listeria monocytogenes and Salmonella) bacteria. The inactivation data were used to fit the log‐linear and Weibull kinetic models. Additionally, the impact of PL on physicochemical properties, lycopene content, total phenolic content, antioxidant activity, and pectin methylesterase (PME) residual activity (RA) was studied. The results demonstrated that the inactivation rate increases with the increase in fluence. Salmonella was most sensitive to PL, resulting in a reduction of 2.55 ± 0.08 log CFU g−1 and a higher kmax, whereas S. aureus was most resistant, with a reduction of 1.87 ± 0.24 log CFU g−1 and a lower kmax. The Weibull model was the best to predict the inactivation kinetics based on standard statistics and information theory criteria. For all assayed food‐borne pathogens, the inactivation curve showed non‐linearity with upward concavity except for L. monocytogenes, which followed a concave downward curve (β >1). Results showed that PL was effective in the retention of color, firmness, pH levels, total soluble solids, and titratable acidity, and also had a positive effect on enhancing the levels of essential components such as lycopene, total phenolic compounds, and antioxidant activity. Additionally, the PME RA significantly decreased with an increase in fluence due to structural modification. Therefore, PL can be explored to enhance fresh‐cut watermelon's safety and quality attributes. Practical Applications: The implementation of this research holds significant potential for practical benefits in the fresh‐cut fruit industry. The findings could revolutionize processing practices, ensuring enhanced microbial safety, enzyme inactivation, and an extended shelf‐life of fresh‐cut watermelon. The study strongly contributes to preserving the desirable texture, color, and overall quality of the product, enhancing the retention of lycopene and other valuable antioxidants by standardizing the pulsed light treatment parameters while adhering to U.S. Food and Drug Administration standards for food application. Moreover, this research will scientifically contribute to addressing the critical challenges of foodborne outbreaks in the fresh‐cut fruit sector while providing consumers with a healthy, convenient food choice. [ABSTRACT FROM AUTHOR]

A novel carbon-based material was synthesized by chemical doping of Iodine (I2) into multilayer graphene (MLG) using photolysis method. Elemental analysis using Energy Dispersive X-ray (EDX) determined low amount of Iodine doping in the graphene. Raman spectroscopy demonstrated increase in number of layers of graphene. Iodine doped graphene (I-MLG) showed a sharp reduction in resistance when exposed to NO2 gas at room temperature. It demonstrated sensing response of 69% for 100 ppm of gas in just 16 seconds at room temperature. When compared with other gases and vapours, I-MLG showed selective sensing towards NO2 gas by reduction in resistance during exposure. Hybrid Material displayed reversible sensing but recovery after the removal of NO2 gas source took 1380 seconds. An electric field assisting sensor element was fabricated to lower the recovery time to 156 seconds after applying negative gate voltage of −15V. Sensing and recovery mechanisms of I-MLG along with effect of electric field are presented. [ABSTRACT FROM AUTHOR]