This paper desctibes a new technological process for soybean oil extraction. The process deals with the combined effect of thermoplastic extrusion of beans and the subsequent action of hydrolytic and proteolytic enzymes in aqueous medium to recover the oil, thus, avoiding solvent application. The thermoplastic extrusion is hndamental for the process, because it facilitates the action of enzymes in oil containing cells, reduces the non-hydratable phosphatides and promotes protein denaturation by reducing the emulsion stability and thus enhancing the oil extraction. The main parameters affecting the oil yield are: the temperature and diameter of the die in the extrusion process, the dilution, the concentration of enzymes and the incubation time of the enzymatic treatment.'Ihe highest yield was obtained under the following conditions: extrusion of beans at 9OoC and exit die of 6 mm, enzymatic incubation time of 6 h, extruded soylwater dilution ratio 1:lO and concentration of enzyme 6%. With these conditions 88% of the oil were obtained after centrifugation. Moreover, the aqueous enzymatic extraction is easier than solvent extraction, and leads to high value products: a solvent-free meal more suitable for human consumption, a protein hydrolysate that can be used as ingredient for liquid foods and an oil of better quality. The non-hydrolyzed meal contains ca 25% of original soybean protein and the residual oil. The protein hydrolysate in the liquid phase contains ca 75% of the total protein in the original grain with a molecular weight below 20 kDa.

Glycerides of known structure have been synthesised, without recourse to protecting groups, by making use of differences in reactivity of primary and secondary hydroxyl groups of glycerol. a-Monoglycerides and aa'-diglycerides of a single acid are prepared from acyl chlorides and glycerol in homogeneous chloroform solution obtained with the aid of NN-dimethylformamide. Monoacylation was assisted by the use of complexing agents. Diglycerides containing two different acids are obtained by treating a monoglyceride with another fatty acid chloride. Triglycerides containing one unsaturated acid are prepared by a three-stage process.MOST syntheses of glycerides are based on the use of protecting groups; the present communication reports syntheses based on the difference in reactivity of primary and secondary hydroxyl groups of glycerol. Although the introduction of certain protecting groups, e.g., triphenylmethyl, depends on the greater reactivity of the primary hydroxyl groups, there seems to be no direct experimental proof of the differing reactivities of hydroxyl

Esterification rates of eight commonly occurring fatty acids were studied at 180C using equivalent and equimolar amounts of glycerol with and without a cosolvent. The esterification with equivalent amounts of glycerol without cosolvent followed second order kinetics and proceeded at a similar rate for all acids examined. Esterifications with equimolar amounts of glycerol were kinetically complex and their speed depended on the solubility of glycerol in individual fatty acids.

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