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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]

Abstract: Enzymatic browning and jaggery formation are the major issues that limit the applications of thermal treatment to sugarcane juice. Kinetics of polyphenol oxidase (PPO) inactivation and formation of reducing sugar (RS) during conventional heating (CH) and Ohmic heating (OH) of sugarcane juice were investigated. The CH treatment was varied from 60 to 90 °C for 300–1,200 s and OH treatment from 24 to 48 V/cm electric field strength (EFS) for 15–75 s at 80 ± 1 °C. PPO inactivation kinetics followed the nth‐order (n = 1.6) for CH while the two‐fraction model was suitable during OH treatment. The inactivation constant k showed a reciprocal quadratic dependency on EFS and temperature. The D‐value for CH varied between 2,635 and 359 s, and for OH, it was between 42 and 96 s for labile and between 0.007 and 0.30 s for stable PPO fractions. The temperature sensitivity (ZT) of PPO was 32.6 °C for CH system; the electric field sensitivities for OH treatment for labile (ZV,L) and stable (ZV,S) fractions of PPO were 69.8 and 15.6 V/cm, respectively. The calculated temperature coefficient (Q10,T) was 2.12, and its analogous electric field coefficients (Q8,V) for labile and stable PPO fractions were 1.28 and 3.00, respectively. The RS formation was low in the range of temperature used during CH treatment but followed the second‐order kinetics during OH system, while the formation rate followed the quadratic dependence. Practical applications: Sugarcane juice is one of the natural refreshing summer drinks in several tropical countries. The processing of sugarcane juice by Ohmic heating (OH) may be a pragmatic alternative method to preserve the fresh juice. The use of Ohmic heating can reduce the treatment temperature of the juice leading to improved quality attributes in the finished product. The inactivations of polyphenol oxidase and sugar inversion due to processing treatments is the two important criteria in such products. [ABSTRACT FROM AUTHOR]

Sugarcane juice was analyzed for the effect of four different time-temperatures (60-90?C for 5-20 min) at three electric field strengths (EFS) (24, 32, and 48 V cm-1) on PPO activity in a lab scale ohmic heater. At 60°C, the activity decreased with increase in EFS while at 70-90°C, increased activity was observed at 32 and 48 V cm21. Up to 97.8% reduction in activity was observed at 32 V cm-1/90°C/5 min. The biphasic model was the best to describe PPO inactivation kinetics. The kinetic analysis showed that the decimal reduction time (D-value, minute) decreased with increasing EFS at different temperatures. At 32 V cm-1/90°C/5 min, the D-value was 8.25 and 76.55 min for labile and stable PPO fractions, respectively. The electric field sensitivity parameter (ZV-value, V cm-1) was lower at 60 and 70°C but increased with treatment temperature. The z-value (z°C) for the labile fraction consistently decreased with increasing EFS and was lower than the stable fraction. Color change was inversely proportional to treatment temperatures at 24V cm-1 and directly proportional at 32 and 48V cm-1. The kinetics for L, a, b values was best described by first order model while colour change was best explained by the combined model. Practical applications Sugarcane juice is one of the most widely relished beverages of south Asia. However, enzymatic browning is a major factor that limits its storage to only a few hours after extraction. High temperatures and processing times employed during thermal processing cause deleterious changes in the color, flavor and the overall nutritive components of the product. Ohmic heating has been applied to different commercial food products (like strawberries, grapes, orange juice) and has been rendered as a time-efficient process. Therefore, this study was conducted to investigate the effect of ohmic heating on inactivation of the browning enzyme (PPO) in sugarcane juice and its kinetic analysis, so as to suggest an alternative that can be explored further for commercial packaging of sugarcane juice. [ABSTRACT FROM AUTHOR]