Plant-based edible coatings for managing postharvest quality of fresh horticultural produce: A review

Fresh fruit and vegetables continue with biological activities after harvest, resulting in continuous loss of water and solutes, and gaseous exchanges with surrounding environment through respiration and transpiration. This contributes significantly to postharvest quality loss because of resultant mass loss, shrivelling, poor eating quality and short shelf life, which are the critical parameters determining the competitiveness of fresh produce in the market. One of the successful techniques used to alleviate water loss of fresh produce is the application of coatings immediately after harvesting. This technique has been successful not only in reducing water loss and delaying senescence but also in increasing the antimicrobial properties of the coated produce. Recently, some substances included in coatings formulations are criticised due to their negative residual effects on consumers, high potential to form an impermeable layer whilst some are prohibited on organic produce. The development of coatings from edible substances is the latest technology intended for safe maintenance and improvement of produce quality at postharvest. The application of edible coatings based on plant extracts (ECPE) on horticultural produce can provide extensive relief to consumers. The use of ECPE stands high chances of increasing consumer confidence because they can be completely organic. This review looks at the maintenance of postharvest quality by application of ECPE on fresh produce. Recent advances in the formulation and application of ECPE are discussed. Furthermore, this review makes recommendations for formulations that could be very valuable in future whilst assisting future research, development of legislation and functionality of ECPE.