Physiological effects of hot water dipping, chitosan coating and gibberellic acid on shelf-life and quality assurance of sugar snap peas (Pisum sativum L. var. macrocarpon)

- Chitosan coating (1%) and gibberellic acid (1 mM) significantly reduced pod decay.
- Chitosan coating improve the quality and extend shelf-life of chilled peas.
- Pea pods treated with Chitosan coating and gibberellic acid retained their sweetness and crispness.

The effects of chitosan coating (CC), gibberellic acid (GA3), and hot water dipping (HWD) to improve quality and extend shelf-life of chilled pea by reducing chilling injury and postharvest decay were evaluated. Pea pods were subjected to treatments consisting of CC (at 1 and 3%), GA3 (at 1 and 2 mmol L−1), and HWD (at 45 °C for 20 min and 55 °C for 1 min) followed by storage at 4 °C in a refrigerator set at 85-90% relative humidity for 35 d. No decay occurred in pods treated with GA3 at 1 mmol L−1 while CC at 1% resulted in 7% decay compared to 22-55% decay by CC at 3% and HWD treatments. Chitosan coating (1%) and GA3 (1 mmol L−1) reduced titratable acidity by 11.5 and 13.4%, respectively and chilling injury by 0.18 and 0.20%, respectively compared to 7% chilling injury by HWD treatments and the untreated control at the end of the storage period. The HWD treatment enhanced active oxygen-scavenging systems, such as peroxidase and catalase compared to CC and GA3 treatments. The content of reducing sugars was stable in all storage periods. Pods treated with CC and GA3 had the highest amount of total chlorophyll (8.4 and 8.9 mg g−1 FW), vitamin C (1.2 and 1.8% mg 100 g−1 FW), phenolics (1.9 and 1.6 mg g−1 FW), and protein (11.5 and 13.2 mg g−1 FW) at the end of the storage period.