Innovative edible coatings for postharvest storage of sweet cherries

Abstract

Sweet cherry is among the most appreciated fruits by consumers, due to its organoleptic and health-promoting properties. However, it is a fruit with reduced shelf life, which limits its availability on the market. Several strategies to improve shelf life of fruits are available, including the use of plant-based edible coatings. This work aims to study the postharvest effect of aqueous (A) and hydroethanolic (H) extracts of medicinal and aromatic plants (Mentha piperita L. (MP), Satureja montana L. (SM) and Thymus vulgaris L. (TV)), Aloe vera (Al), and chitosan (Qh) coatings on physical and quality parameters of cv. Early Bigi. Sweet cherries were stored at 2°C for 14 days (cold storage), then kept at 20°C for more three days to assess shelf life (+ 3 SL). All treatments reduced weight (average of 10%) and firmness (average of 0.9 Nmm-1) losses mainly at the end of cold storage + 3 SL, when compared to control samples (12% and 0.7 Nmm-1). The ripening index showed a delay (average of 20 and 14%, respectively to cold storage and cold storage + 3 SL) in its increase when using aqueous extracts of Satureja montana L. (SMA) and Thymus vulgaris L. (TVA) coatings. Coatings improved the overall antioxidant activity of sweet cherries, without negative effects on the content of bioactive compounds and on the sensory profile of fruits. SMA and TVA coatings present overall positive results, that might indicate that their use could be a safe, natural, effective, beneficial and innovative approach to preserve sweet cherry quality in postharvest storage.