The effects of alkali cooking on the yields of crude and neutral oil from cottonseed meats

Abstract

SummaryEqual quantities of flaked cottonseed meats of identical composition were similarly cooked at high moisture conditions with and without alkali present. The cooked flakes were exhaustively extracted with commercial hexane, and the yields of crude oil, neutral oil, and meal were determined. The yields from an equal quantity of uncooked flakes were similarly determined, chiefly to serve as a neutral oil control. Analyses of the crude oils and meals were compared to determine the effects of the presence of alkali while cooking on the composition of the products.These experiments show that there was a reduction in the yields of both crude and neutral oil resulting from the admixture of alkali with cottonseed flakes while cooking. Assuming yields from flakes cooked with water as 100%, and average of 0.6% less crude oil was obtained from alkali‐cooked than from watercooked flakes. A similar comparison of the yields of neutral oil shows that those from the alkali‐cooked flakes averaged about 0.75% less than from the flakes cooked with water.The crude oils from alkali‐cooked flakes contained only about one‐fifth as much gossypol as those from the water‐cooked flakes and were appreciably lower in free fatty acids. The crude oils from alkali‐cooked flakes were significantly higher in phosphorus. The sodium content of the oils from alkali‐cooked flakes indicated that their content of soaps ranged from 0.07% to 0.19%.