Authors: Meenal Maan, Priyanshi Gupta, Dr. Rishabh Bhardwaj
Abstract: Enzymatic browning represents one of the most significant post-harvest challenges affecting fresh fruits and vegetables, leading to rapid deterioration in visual appeal, flavor, texture, and nutritional quality. This phenomenon primarily occurs due to the activity of polyphenol oxidase (PPO), which catalyzes the oxidation of phenolic compounds into quinones that subsequently polymerize into brown pigments. Such changes not only reduce consumer acceptability but also contribute to substantial economic losses in the food industry. In recent years, increasing consumer awareness regarding food safety and the demand for clean-label products have led to a shift away from synthetic antioxidants such as BHA and BHT toward natural alternatives. Natural antioxidants derived from plant sources are considered safer, environmentally friendly, and beneficial for health due to their additional bioactive properties. The present study focuses on evaluating the comparative effectiveness of selected natural antioxidants—ascorbic acid, citric acid, fresh lemon juice, sodium chloride, and calcium chloride—in inhibiting enzymatic browning in fresh-cut apple slices (cv. Fuji). The samples were treated with different concentrations of these agents and monitored over a period of 120 minutes under controlled conditions. Browning intensity was assessed using a standardized visual scale, and percentage inhibition was calculated relative to untreated controls. Additionally, in-vitro antioxidant assays such as DPPH and ABTS were performed to validate the radical scavenging capacity of the tested compounds. The results demonstrated that ascorbic acid exhibited the highest efficacy, completely inhibiting browning at higher concentrations. Lemon juice also showed strong antioxidant activity due to the synergistic presence of ascorbic acid, citric acid, and flavonoids. Citric acid displayed moderate effectiveness by reducing pH and chelating metal ions, while sodium chloride and calcium chloride showed comparatively lower inhibitory effects.
DOI: http://doi.org/10.5281/zenodo.20321255
