Effect of chitosan coating incorporated with pomegranate peel extract on pear fruit softening, quality, and cell wall degrading enzymes during cold storage

Abstract

Pear fruit is vulnerable to textural softening and quality loss during long-term storage. Therefore, in the present studies, the effect of chitosan coatings (CH 1% and CH 2%), pomegranate peel extract, and chitosan-enriched pomegranate peel extract (CH 1%+PPE and CH 2%+PPE) coatings was investigated on pear fruits stored at 01°C and 90%95% relative humidity for 67 day. The results revealed that the combination of chitosan coating with pomegranate peel extract (CH 2%+PPE) markedly reduced the mass loss, spoilage, and maintained the firmness of pear fruit during the storage. In addition, the combined CH +PPE coatings resulted in higher sensory quality, soluble solid content (SSC), pH, and solid acid ratio as compared to the control fruit. Further, the CH+PPE coatings resulted in the lower activities of polygalacturonase (PG), pectinmethylestarase (PME), and cellulase enzymes in the stored pear fruits. The lower cell wall metabolism of treated fruits was associated with the reduced membrane permeability as well as the malondialdehyde content (MDA) which contributed to higher fruit firmness during storage. Thus, among all the treatments, CH 2%+PPE was most effective in retaining fruit firmness and quality by lowering the activity of cell wall degrading enzymes during long-term storage. Practical applications Pear fruits cv. Punjab Beauty tends to soften and deteriorate rapidly during the long-term storage. Chitosan coating enriched with pomegranate peel extract has been reported to preserve postharvest quality in fruits. This study reported that combined CH +PPE coatings could be explored as a potential approach for maintaining the fruit firmness and postharvest quality in pears during a low-temperature storage.