Effect of postharvest application of chitosan coating containing green tea extract on quality characteristics and shelf life of Selva strawberry cultivar

Strawberries are one of the most susceptible fruits to spoilage, mechanical damages and physiological detoriaration and have a high rate of metabolism during storage. In this study, chitosan (1%) containing different concentrations of green tea extract (10, 20 and 30 %) was used as a coating for Selva strawberry fruits. Quality parameters including weight loss, pH, acidity, soluble solids, total anthocyanins, texture, color parameters (Lab), microbial count (total bacteria, molds and yeasts) and sensory attributes were assessed during 16 days of storage at 4 °C. Weight loss, pH, soluble solids, total bacteria, molds and yeasts extension were increased, and acidity, total anthocyanin and firmness were decreased during storage. Strawberries coated with chitosan containing green tea extract had a lower weight loss, pH, soluble solids and higher acidity, total anthocyanin, and firmness than control. The results showed that coating Selva strawberry fruit with chitosan containing green tea extract improved color parameters and decreased microbial count during storage. Increase in the concentration of green tea extract resulted in synergistic effects with chitosan, so that 1% chitosan coating containing 30% green tea extract showed the highest effects in improving quality attributy and extending the shelf life of fruits.