Tragacanth gum coating modulates oxidative stress and maintains quality of harvested apricot fruits.

Tragacanth gum is a polysaccharide-based complex with a good coating property. However, its use in postharvest storage of fresh fruits and vegetables is very limited. In the current work, the effect of tragacanth gum (1%) was investigated on postharvest quality of apricot fruits during storage at 20 ± 1 °C for 8 days. Apricot fruits coated with tragacanth gum coating showed significantly reduced weight loss, decay and electrolyte leakage, hydrogen peroxide and malondialdehyde production. Tragacanth gum coating suppressed increase in total soluble solids and showed higher titratable acidity compared with control. The coated fruits had higher total phenolics and ascorbic acid along with greater 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity in contrast with control. Postharvest application of tragacanth gum coating maintained markedly higher activities of ascorbate peroxidase (APX), catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD) enzymes activities as compared with control. In addition, tragacanth gum application suppressed polygalacturonase (PG), pectin methylesterase (PME), and cellulase (CX) enzymes activities, thereby suppressed softening of apricot fruits. Sensory quality attributes such as taste, juiciness, aroma, appearance, and overall acceptability were also significantly higher in tragacanth gum coated fruits compared with control. In conclusion, tragacanth gum coating could be considered suitable for postharvest quality conservation of apricot fruits.