Combination of chitosan coating and heat shock treatments to maintain postharvest quality and alleviate cracking of Akebia trifoliate fruit during cold storage

Akebia trifoliata fruit cracks easily, which shortens the shelf life and declines commercial value. This work aimed to evaluate the effects of heat shock and coating treatments on postharvest quality of A. trifoliata fruit and to elucidate the mechanism underlying retarding cracking by cell wall metabolism. Coating could decline cracking incidence (from 16.05% to 3.61%), decay incidence (from 31.21% to 18.06%), total soluble solids (TSS), and malondialdehyde (MDA) content compared to uncoated treatment during 35 days of storage. Heat shock could further decrease decay incidence but did not influence TSS, pH, firmness, and starch. Heat shock at 40 °C combined with coating treatment had the best preservation performance with the highest synthetic score (4.41). Furthermore, coated fruit displayed lower β-glucosidase and polygalacturonase activities which resulted in higher cellulose and Na2CO3-soluble pectin. These modifications together with lower weight loss, MDA, and ion leakage contributed to the lower cracking incidence.