The study investigates the influence of pulsed light (PL) processing parameters on quality of mixed fruit beverage followed by kinetic modeling. The attributes tested were aerobic mesophiles (AM), yeast and mold (YM) counts, polyphenol oxidase (PPO) and peroxidase (POD) activity, color change (ΔE*), browning index (ΔBI), antioxidant capacity (AOC), and ascorbic acid (AA) content at varying voltage (1.8–2.4 kV), the number of pulses (2–187), and distance (2.4–9.6 cm). Weibull model described the PL inactivation rate of AM and YM and nth order kinetic model estimated the inactivate rate of PPO, POD, and AA. The maximum inactivation of PPO, POD, and AA content were 41, 51, and 36%, respectively. At the most severe PL condition, ΔE* was 6.4, ΔBI was 5.6 with 14% increment in phenolics. A secondary kinetic model adequately predicted the ratio of rate constant and fluence‐based rate (k/kF) for PPO, YM, and AA correlating voltage (V) and lamp distance (x). PL‐induced pasteurization of the beverage is possible at the fluence rate of 17.42 W/cm2 for 3 min. Practical Applications Exposing the food material to a high intensity pulsed light (PL) is a nonthermal way of food preservation for the shelf‐life extension. The potential of PL treatment (PLT) has been explored for a mixed fruit beverage in terms of its microbial, enzymatic, and nutritional quality. An optimized PLT condition is proposed to obtain a microbially safe fruit beverage along with a minimal loss in bioactive compounds. Subsequently, the kinetic data related to microbial and enzyme inactivation and degradation of vitamins will help in deciding the process parameters like treatment time, lamp voltage, and sample distance from the light source. The secondary kinetic model will eventually help to design a robust PL process condition for similar fruit beverages to obtain a microbiologically safe product with a minimal loss in vitamins.

Pulsed light (PL) is a polychromatic radiation‐based technology, among many other non‐thermal processing techniques. The microbiological lethality of the PL technique has been explored in different food matrices along with their associated mechanisms. Pasteurization of fruit juice requires a 5‐log cycle reduction in the resistant pathogen in the product. The manufacturers look toward achieving the microbial safety and stability of the juice, while consumers demand high‐quality juice. Enzymatic spoilage in fruit juice is also a crucial factor that needs attention. The retailers want the processed juice to be stable, which can be achieved by inactivating the spoilage enzymes and native microflora inside it. The present review argued about the potential of PL technology to produce a microbiologically safe and enzymatically stable fruit juice with a minimal loss in bioactive compounds in the product. Concise information of factors affecting the PL treatment (PLT), primary inactivation mechanism associated with microorganisms, enzymes, the effect of PLT on various quality attributes (microorganisms, spoilage enzymes, bioactive components, sensory properties, color), and shelf life of fruit juices has been put forward. The potential of PL integrated with other non‐thermal and mild thermal technologies on the microbial safety and stability of fruit juices has been corroborated. The review also provides suggestions to the readers for designing, modeling, and optimizing the PLT and discusses the use of various primary, secondary kinetic models in detail that have been utilized for different quality parameters in juices. Finally, the challenges and future need associated with PL technology has been summarized.

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The study aims to formulate a mixed fruit beverage through sensory analysis, and the composition was optimized using a fuzzy logic algorithm. The fuzzy optimization algorithm was developed using a modified Takagi and Sugeno's approach, polynomial mixture modeling, and nonlinear solver engine. The optimized blend consisted of amla juice, pineapple juice, and coconut water in 14.3, 63.0, and 22.7%, respectively. Further, the batch thermal treatment was carried out within 50 to 95 °C for an isothermal holding time of 1 s to 10 min, and pasteurization condition for the beverage was estimated from kinetic modeling. The concept of thermal pulse inactivation due to non‐isothermal heat‐up‐time and cool‐down‐time has been introduced within the process time calculation. From the kinetic study, polyphenoloxidase enzyme appeared to be the most resistant entity towards inactivation among all the natural microbiota and quality deteriorating enzymes. Pasteurization in terms of achieving a 5D reduction of both aerobic mesophilic and yeast‐mold counts was attained over a range of 80 to 95 °C for 10.2 + 1.4 to 3.1 + 2.0 min (1.4 and 2.0 min = heat‐up‐time + cool‐down‐time), respectively. The 90% inactivation of both polyphenoloxidase and peroxidase enzymes was obtained over a range of 90 to 95 °C for 12.8 + 1.7 to 8.4 + 2.0 min, respectively. While obtaining both the microbial and enzyme stability at the isothermal condition of 95 °C for 8.4 min, the corresponding retention in ascorbic acid, total phenolics, and antioxidant capacity were observed as 49.7, 63.0, and 61.4%, respectively.Practical ApplicationIn this work, the formulation of a fruit blend was optimized through an intelligent optimization technique (fuzzy algorithm) applied to the sensory data set. The approach for calculating thermal processing time or pasteurization condition provides a new dimension with better precision. The thermal treatment condition of 95 °C for 10 min can be used for this mixed beverage to achieve both microbial stability (5‐log reduction) and enzyme stability (90% reduction). The presented study can be used as a reference for other similar beverages to achieve a complete process design from basic formulation optimization to thermal (batch‐type) processing conditions.

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