Utilization of seed from Cucurbita maxima, a pumpkin variety of Bangladesh, converting into refined oil and oilcake

Abstract

Pumpkin seed oil, also called as pepita oil can be a substitute of conventional edible oil now a days. A method has been developed to use this under-utilized pumpkin seed which is a common vegetable in Bangladesh. This study suggests finding a new alternate of edible oil as well as proper utilization of nutritionally rich pumpkin seed rather than wasting into the environment. Pumpkin seed oil was extracted from dried pumpkin seed by expeller and it was purified by the refining steps-degumming, neutralization, deodorization and bleaching. The crude and refined oil were characterized. Acid value was decreased from 2.36 to 0.34 mg/ g as KOH (Potassium Hydroxide); color was lightened from Yellowness (Y) = 20, Redness (R) = 20 to Yellowness (Y) = 6, Redness (R) = 3; moisture was decreased from 0.26 to 0.05%; insoluble impurities was changed from 0.32 to 0.05% and unsaponifiable matters has been lowered from 2.17% to 0.92%by refining where no fundamental changes occurred in iodine value, saponification value, peroxide value, refractive index and specific gravity after refining. The characteristic parameters were within the limits mentioned for edible oil in codex. Fatty acid composition remained same, although total tocopherol decreased from 361.9 mg/kg to 300.69 mg/kg. The observed pumpkin seed oil was rich in linoleic and oleic acid- 36.43 and 36.89%. The nutritional benefits of oilcake found after oil extraction were determined also. Protein and fat was 54.78% and 4.16% respectively as well, iron, calcium, magnesium and manganese was found 30.29, 21.45, 2.27 and 0.30 mg/ 100 g respectively in oilcake.