Physico-chemical and enzymatic changes in low temperature stored plum fruits in response to putrescine application

Plum is a perishable fruit and its ripening coincides with the hot and dry summer months under north Indianconditions. It has very short storage life at ambient temperature and high postharvest losses. An experiment wasplanned to extend the post-harvest life of plum fruits with putrescine application under cold storage conditions. Physiologically mature and uniform fruits of plum cv. Satluj Purple were dipped in different concentrations ofputrescine (0.0, 1.0, 2.0 and 3.0 mmol l−1) for 5 min. Treated fruits were air-dried in shade and packed in corrugatedfiber board boxes with paper lining before storage at 0–1˚C and 90–95% RH for 35 days. Results revealed thatfruits treated with putrescine @ 3.0 mmol l−1 retained the acceptable quality by reducing physiological loss inweight, spoilage, pectin methyl esterase activity and maintaining the fruit firmness, sensory quality, total solublesolids, titrable acidity, total sugars, reducing sugars and non-reducing sugars up to 28 days of storage.