GB590916A - Process for improving fats and fatty oils for food and other purposes - Google Patents

Abstract

The consistency-temperature characteristics of fats and hydrogenated fatty oils are altered by subjecting a mixture of the fat and a fraction from a previous cycle of operations to a process of catalytic redistribution of the fatty acid radicals among the glycerides (as for example described in Specification 574,807) followed or accompanied by separation of the glyceride by fractional precipitation from solvents and filtration. This cycle may be repeated an indefinite number of times and is so controlled that the amount and iodine value of the fraction withdrawn for use at the end of each cycle are substantially the same as those of the fresh fat entering at the beginning of each cycle. Fats and/or hydrogenated fatty oils may thus be rendered more suitable for use in certain food industries either by being given sharper melting points, or, conversely, by being made to retain their plastic properties over a wider range of temperature. In an example 100 parts of hydrogenated soybean oil were subjected to fatty acid redistribution by contacting for 45 minutes at 120 DEG F. with 0.4 per cent. sodium methoxide catalyst, the latter inactivated and removed, and the saturated triglycerides partially precipitated from a solution of the rearranged oil in acetone-alcohol by cooling to 65 DEG F. The precipitate was filtered off and 4.8 parts of solid obtained (fraction A). The filtrate on cooling to 20 DEG F. and filtering yielded 38.2 parts of liquid (solvent free)-fraction B, and 57.0 parts of solid (solvent free)-fraction C. Fractions A and B when mixed constituted the finished product for use (43 parts) and fraction C (57.0 parts) was mixed with 43 parts of fresh hydrogenated soybean oil, the mixture subjected to a second cycle of operations and so on. After the 3rd cycle the amounts of the fresh oil entering the 4th cycle and of the fraction ready for use constituted 49.9 and 50.1 per cent. respectively of the original charge and the iodine value of the fractions for use was 76.9, i.e., substantially the same as that of the fresh oil entering the process (77.8). The product for use was softer at low temperatures and firmer at high temperatures than the untreated hydrogenated oil, and showed a wider gap between the softening point and final melting point when heated.ALSO:Shortenings, margarine fats, confectioners' butters &c. which are of sharper melting point or are, conversely, plastic over a wider range of temperature are made by subjecting a mixture of fat and a fraction from a previous cycle of operations to a process of catalytic redistribution of the fatty acid radicals among the glycerides (as, for example, described in Specification 574,807) followed or accompanied by separation of the glycerides by fractional precipitation from solvents and subsequently filtering. The cycle may be repeated an indefinite number of times and so controlled that the amount and Iodine Value of the fraction withdrawn for use at the end of each cycle are substantially the same as those of the fresh fat entering at the beginning of each cycle. In an example 100 parts of hydrogenated soybean oil were "rearranged" using sodium methoxide as catalyst, the latter inactivated and removed, and the saturated triglycerides partially precipitated from a solution of the rearranged oil in acetone-alcohol by cooling to 65 DEG F. The precipitate was filtered off (fraction A). The filtrate was cooled to 20 DEG F. and the further precipitate obtained filtered off and freed from solvent (fraction C). The filtrate after removal of the solvent constituted fraction B. Fractions A and B when mixed constituted the finished product for use and fraction C was mixed with a fresh charge of hydrogenated soybean oil, the mixture subjected to a second cycle of operating, and so on.