R. Basu Roy Choudhury

The preparation and purification of monoglycerides

Mono- and diglycerides were produced by reacting the following oils with glycerol: coconut, peanut, sesame, linseed, and sardine. It was shown that the yield of monoglyceride was not dependent upon the fatty acid composition of the oil but on the solubility of glycerol in oil, which is dependent in part on the temperature. An excess of glycerol above that which is soluble does not change the composition of the reaction product. At 180°C, no more than 45% monoglycerides can be formed by glycerolysis.

The preparation and purification of monoglycerides. II. Direct esterification of fatty acids with glycerol

Studies have been made on the direct esterification reaction with various saturated and unsaturated fatty acids using more than theoretical concentration of glycerol (for maximum monoglyceride production) at 180C reaction temperature and in presence and absence of alkaline catalyst. The results show that the maximum monoglyceride formed is in the range of 55–60% of the fatty product at equilibrium stage of the reaction. The alkaline catalyst substantially increases the initial rate of reaction without appreciably lowering the time required for reaching the equilibrium concentration of monoglyceride in the resulting reaction mixture. Catalyst helps in depressing diglyceride formation.

Ethanol extraction of soybean oil

Extraction of soybean flakes with 90, 95, 98 and 100% ethanol resulted in more rapid lipid and less rapid non-lipid removal with the increasing ethanol concentrations. There was little difference in the quality of the oil produced by the different solvents. Protein content of the residual meal averaged 52.1%.

The fatty acid composition of cottonseed oil at various stages of solvent extraction

The variation in the fatty acid composition of the glyceride portion of cottonseed oil at various stages of solvent extraction has been investigated. Prime cottonseed meats were flaked and extracted in glassware rate extraction apparatus, using commercial hexane up to different degrees of extractions. The fatty acid composition of cottonseed oil obtained after extracting the flakes to different residual oil contents was determined by gas-liquid partition chromatography. No difference was found.

Extraction of soybeans with four hydrocarbon solvents

Soybean flakes were extracted in glass extraction apparatus with four hydrocarbon solvents: hexane, isohexane, pentane, and isopentane. The amount of extracted oil was determined at 10 min intervals for 60 min. The extraction rates of the solvents increased in the following order: isopentane, pentane, isohexane, and hexane. Quality and fatty acid composition of the oils extracted by the four solvents showed no significant differences.

Hexane and ethanol as peanut oil solvents

Absolute ethanol is a better solvent for extracting peanut grits than 95% ethanol, with hexane intermediate in its action. More nonlipids solids are extracted by 95% ethanol than absolute ethanol as compared with none by hexane. Ethanol-extracted oils are slightly higher in color and free fatty acids than hexane-extracted oils.

Relation of the quality of solvent-extracted soybean oil and residual oil content of meal

Flaked soybeans were extracted by commercial hexane in a continuous countercurrent pilot-plant and in glass extraction-rate apparatus. The quality of the oil extracted at various stages was evaluated in terms of iodine value, saponification value, refractive index, color, refining loss, free fatty acids, phospholipids, and neutral oil. As the residual oil content of the meal decreased, the refining loss, phospholipid content, and color of the extracted oil increased. There was no significant change in other properties. The maximum amount of refined oil was obtained with a meal containing about 1% residual oil.

Solubilities of five triglycerides in aqueous ethanol

The solubilities of trilaurin, trimyristin, tripalmitin, tristearin, and triolein in 90, 95.4, 98, and 100% ethanol between 40C and 90C were determined. The data were compared with data calculated by the ideal solution law.