Postharvest Chemical Treatments for Extending Shelf Life and Preserving Fruit Quality

Fruits are highly perishable and often lose quality soon after harvest due to rapid ripening, moisture loss and microbial decay. These postharvest losses reduce both the nutritional value and marketability of fruits, affecting both farmers and consumers. Globally, postharvest losses in fruits are estimated to range between 20% and 50%, with higher percentages reported in tropical and developing regions. To mitigate these challenges, various postharvest management strategies have been developed, among which chemical treatments and edible coatings have gained considerable attention. Chemical treatments, including calcium chloride, calcium lactate, ethylene inhibitors such as 1-methylcyclopropene (1-MCP) and natural plant-based antimicrobials, play a crucial role in delaying senescence and maintaining fruit firmness. Calcium salts help strengthen cell wall structure and reduce enzymatic softening, while ethylene inhibitors suppress ripening processes by blocking ethylene action. Natural plant extracts and organic acids exhibit antimicrobial properties that help control postharvest pathogens and reduce spoilage. Edible coatings represent an eco-friendly and sustainable alternative to synthetic packaging materials. These coatings are composed of biodegradable materials such as polysaccharides (e.g., starch, chitosan, alginate), proteins (e.g., whey protein, gelatin) and lipids (e.g., waxes, fatty acids). When applied to fruit surfaces, edible coatings form a thin, semi-permeable barrier that regulates gas exchange, reduces water loss, delays oxidative reactions and limits microbial contamination. Moreover, edible coatings can serve as carriers for functional additives such as antioxidants, antimicrobials and nutraceutical compounds, further enhancing their protective effect. Together, these technologies play an important role in reducing postharvest losses, improving storage stability and supporting food and nutrition security.