Effect of harvest maturity on quality and shelf life of pumpkin (Cucurbita moschata Poir.)

Abstract

The research project "Effect of harvest maturity on quality and shelf life of pumpkin (Cucurbita moschata Poir)" was carried out at the Department of Processing Technology, College of Horticulture, Kerala Agricultural University, Thrissur during the period November 1999 to January 2001. The major objective was to study the effect of harvest maturity III relation to source of nutrition on the physico-chemical constituents and shelf life of three varieties of pumpkin viz., Co. 1 , Ambili and Suvarna. The observations revealed that the varieties differed significantly in physical attributes like circumference, polar diameter, flesh thickness, cavity index and physical composition. Varieties also showed significant variation in content of TSS, sugar, ascorbic acid, P carotene, starch and crude fibre. Ambili had the ideal characteristics required of a pumpkin variety viz., early maturity, high flesh recovery and low seed and placenta per cent and hence a low waste index. Suvarna had better nutritional and processing attributes as indicated by yellowish orange colour, high P carotene, TSS and acidity. The physical parameters like fruit weight, polar diameter, circumference, flesh thickness and cavity volume showed an increasing trend while seed and placenta percentage showed a decreasing trend with maturity. Chemical constituents like TSS, total sugars, acidity, P carotene and crude fibre increased with maturity while starch declined after reaching a maximum value at 45 days

after anthesis (d.a.a.). Fruits harvested at 45 d.a.a. had longer shelf life. The physiological loss in weight was maximum when fruits were harvested at 30 d.a.a. Fruits of variety Ambili can be harvested 45 days after anthesis for better fruit weight, maximum flesh thickness, sensory quality and less PL W in storage. The optimum maturity for harvest of variety Suvarna is 60 days after anthesis in both seasons for maximum fruit weight, ~ carotene, TSS, total sugars and longer shelf life. For economic yield Co.l should be harvested at 45 d.a.a. in summer and 60 d.a.a. in rainy season. However in all the varieties an improvement in quality of fruits as evidenced by high ~ carotene, TSS, total sugars and acidity was observed when harvest was delayed upto 60 days after anthesis. Inorganic nutrition had a favourable effect on physical composition of fruits while organic nutrition improved the quality by increasing TSS, reducing sugars, ~ carotene and decreasing crude fibre content.