Enhancing fresh-cut pineapple shelf-life: exploring the impact of ultrasonic-homogenized alginate coatings

Purpose: This study investigates the influence of ultrasonic-homogenized alginate-based coatings on the quality and shelf-life of fresh-cut pineapple. As preservation of fresh-cut produces is still a challenging task for both producers and distributors. Research method: Alginate emulsion was prepared using sodium alginate, distilled water and glycerol. The primary emulsion was formulated by adding olive oil, citral and cinnamic acid into sodium alginate solution and subjected to ultrasonic homogenization for varying durations (۰, ۲۰, ۴۰, and ۶۰ minutes) at a fixed amplitude of ۲۰ kHz. Changes in physicochemical properties, microbial activity, browning enzymes and sensory evaluation were studied after application of emulsions followed by storage under refrigeration. Findings: The viscosity of the resulting solutions decreased significantly from ۱۱۰.۸۴±۲۵.۶۷ mPa×s to ۱۷.۷۵±۱.۵۹, ۱۰.۴۱±۰.۵۴, and ۷.۷۴±۰.۳۹ mPa×s, respectively, while the average droplet diameter decreased to approximately ۳۰۰ nm, indicating a shift from heterogeneous to homogeneous particle size distribution. Application of alginate-based coating effectively preserved freshness of pineapple, maintaining color and firmness, minimizing hydrogen peroxide and malondialdehyde accumulation and reducing weight loss percentage. Furthermore, it retained levels of ascorbic acid and total phenolics, delayed enzymatic activities such as polyphenol oxidase, peroxidase and phenylalanine ammonia-lyase and inhibited growth of mesophilic bacteria, yeasts and molds compared to control and primary emulsion coated samples. Research limitations: There were no limitations. Originality/Value: The study extended shelf-life of fresh-cut pineapple up to ۱۲ days when stored at ۵°C±۱°C. The findings underscore the efficacy of ultrasonic-homogenized alginate coatings in improving coating solution homogeneity, thereby enhancing functionality as an edible coating for fresh-cut pineapple preservation.

کلیدواژه ها:

Antimicrobial ، edible coating ، Emulsion ، Fruit firmness ، storage