Removal of gossypol from cottonseed by solvent extraction procedures

Abstract

SummaryThe relative efficiencies of organic, polar solvents and of solvent‐water pairs for use in the extraction of gossypol and related compounds from cottonseed flakes were determined in a specially devised glass laboratory extractor.Of the solvents tested a butanone‐water pair containing 10% of water by volume was the most effective, and chlorine‐substituted hydrocarbons were the least effective. Under equilibrium conditions maximum extraction of gossypol was obtained with a butanone solvent containing 2.5% of water by weight. The rate of extraction of gossypol from cottonseed meal with butanone‐water pairs increased with increase in the amount of water in the system and with increase in temperature of the extraction system. The greater amounts of water in the extraction system resulted in swelling and packing of the flakes and in a decrease in extraction efficiency. Flakes extracted at 26°C. contained 0.08% free gossypol and those extracted at 71°, 0.054%. This decrease may be due, in part, to the reaction of gossypol with the protein to form bound gossypol.

Cottonseed: A sustainable contributor to global protein requirements

“…They used four different concentrations of ethanol (91.5%, 95.4%, 98% and 99.9%) and three different temperatures (65 °C, 70 °C, and 78.3 °C) with extraction times of 10 to 100 minutes. Dechary et al (1952) employed ten different solvents, viz. methanol, ethanol, dioxane, butanone, acetone, isopropanol, chloroform, 1,2-di-chloroethane, perchloroethylene and trichloroethylene, for the extraction of gossypol from cottonseeds in their study.…”

Cottonseed colour fixed pigments. Part III. Prevention of colour fixation and removal of colour‐fixed pigments

“…Bands characteristic for colour-fixed pigments were reported at wavelength ranges from 435 to 450 nm [29,30]. The 445 nm band did not appear in colour-fixed oil before refining because it is masked by the gossypol abwrption [4,5,29].…”

Nutritional Variation in Cottonseed, Effect of Autoclaving in Presence and Absence of Gossypol on Solvent Extracted Cottonseed Meal

“…The meal used in this series of experiments was produced from prime quality cottonseed by successive extractions with hexane and butanone, reducing the free gossypol content to 0.02% and the total gossypol content to 0.2%. The solvents were evaporated by a minimum amount of heat to avoid damage to the protein material (5). This type of meal has been well characterized because it has been used as a standard in nutri- % by weight of meal added as 2% solution of gossypol in refined and bleached cottonseed oil.…”

“…Meals to which oil had been added were extracted with commercial petroleum ether at room temperature prior to grinding and re-extracted following grinding until the residual oil content was reduced to the level in the original meal (approximately 0.3%). Residual free gossypol was removed from the autoclaved meals by extraction with 2% aqueous butanone at room temperature until the free gossypol content was 0.03% or less (5). All extracted meals were reground before chemical and nutritive investigations.…”

“…Studies of holocellulose prepared from common forages are quite limited. Reports of holocellulose prepared from materials other than wood are principally concerned with preparations derived from corn cobs (4,19), straw (7, 2, 4, 77), cornstalks (4-6), Kentucky bluegrass (4), timothy hay (4), oat hay (.5), and mixed hay (5).…”