Effect of chitosan coating containing carvacrol on postharvest quality of guava fruit

Authors: SHU, CHANG - Oak Ridge Institute For Science And Education (ORISE); KIM-LEE, BEATRICE - Waiakea High School; Sun, Xiuxiu

Submitted to: Institute of Food Technologists (IFT) Nonthermal Processing Divison
Publication Type: Abstract Only
Publication Acceptance Date: 3/1/2023
Publication Date: N/A
Citation: N/A

Interpretive Summary: Chitosan coating containing carvacrol improves the postharvest quality of guava fruit. It can be applied as an effective strategy in the postharvest and food industries.

Technical Abstract: Guava (Psidium guajava L.) is an important economic crop grown widely in tropical and subtropical regions. It is a highly palatable fruit that is a rich source of nutrition. As a climacteric fruit, guava exhibits fast ripening and senescence, resulting in a short storage and shelf life. The incorporation of essential oil into a chitosan matrix can reduce the diffusion rate of the oil, thus maintaining a high concentration of essential oil in contact with the food surface for a longer period, more efficiently preventing or mitigating the effects of contamination. Using chitosan-essential oil coatings or nano-emulsions can improve the preservation of fruit with respect to postharvest quality and fungal decay. Guava fruit were coated with different forms of chitosan to determine the optimum molecular weight and concentration for a chitosan-based coating. Then the selected chitosan coating had carvacrol mixed in to generate a nano-emulsoid solution containing 0.1 and 0.2 % (v/v) carvacrol, using a sonic dismembrator. Guava fruit were coated with this emulsion and various parameters for postharvest quality were measured during storage at 20 ± 1 °C RH = 80 ± 5% for 8 days. The results illustrated that a 2% high molecular weight (310-375 kDa) chitosan coating exerted the best preservation effect in terms of postharvest quality parameters. Chitosan coating containing 0.2% carvacrol better maintained postharvest quality compared to the coating with chitosan alone, resulting in higher firmness, soluble solid content, and total acid, and lower weight loss, pericarp browning, and decay rate. A chitosan-carvacrol food coating can reduce postharvest losses. It can be applied as an effective strategy to preserve postharvest fruit and vegetables.