Effects of Gamma Rays on the Keeping Quality of Pumpkin Powder (Cucurbita Pepo L.)

Pumpkin powder (Cucurbita pepo L.) can be used as food diversification originally derived from plant as local product and raw material for making jam, cookies, spaghetti and instant noodles. Effects of gamma irradiation on pumpkin powder at medium doses during storage was observed. Whole pumpkin was cut into small pieces, then blanched at 90 oC for 5 min. followed by transforming it into paste form using wet grinder. The pumpkin paste was dried using drum drier then powdered by willey mill until a 60 mesh particle size was obtained. The powder was packed in a high density polyethylene (HDPE) pouch at 0.01 mm thickness. Pumpkin powder was irradiated at doses of 3 and 5 kGy respectively then stored at 28-30 oC for 2 and 4 months, respectively. Unirradiated individual pouch was also used as control. Irradiation with doses of 3 dan 5 kGy could reduce 2 log cycle of total bacterial count, no mold nor yeast growth in irradiated samples. Irradiation with doses of 3 and 5 kGy could effectively reduce the microbiological counts of the pumpkin powder observed. Pumpkin powder originated from 2 different habitat i.e., Cipanas and Brebes did not show any differences in some physico-chemical characteristics such as moisture content, Aw, protein, fat, starch, amylose contents, colour, but significantly different in sugar content. Both radiation and storage treatments could significantly reduce some of the physico-chemical characteristics of the investigated samples, but did not affect the general quality of pumpkin powder. (author)