CS240645B1 - Tocopherol concentrate production method - Google Patents

Abstract

A tocopherol concentrate is produced of by-products formed during the process production and processing of vegetable oils, eg deodorant condensates. Preparation includes only physical operations, and by vacuum distillation and crystallization. First, by two-stage vacuum distillation preparing a distillate that dissolves in acetone by cooling the solution accompanying substances crystallize separates. It is distilled off from the mother liquor acetone and the degustation residue are subjected to two-stage vacuum distillation. The final product contains 45 to 60% wt. tocopherols.

Description

The invention relates to a process for the production of tocopherol concentrate from by-products from the production and processing of vegetable oils by a relatively simple process involving only physical operations, i.e. distillation and crystallization.

Tocopherols are tocol methyl derivatives, characterized by the action of vitamin E, which is particularly pronounced for alpha-tocopherol (5,7,8-trinetyltolu). Other tocol methyl derivatives called beta-, gamma- and delta-tocopherol have an antioxidant effect. The tocopherols can be prepared synthetically, but they are preferably prepared from various plant materials. Suitable starting materials for the preparation of tocopherol concentrates are vegetable oils, resp. certain by-products resulting from the manufacture and further processing of these oils, eg from deodorizing condensate.

This is caused by washing the vapors of the vapors with oil during deodorization of vegetable oils and fats. The deodorant condensates usually contain 1 to 12 wt. tocopherols, in addition to triacylglycerols, free fatty acids, steroid compounds and other accompanying substances.

According to known processes, the tocopherol concentrates are obtained from said by-products by extraction, distillation or adsorption, or a combination thereof. According to British Patent No. 1,030,514, free fatty acids are first esterified in the starting material with an alcohol containing up to 6 carbon atoms in the presence of a strong acid. This is followed by selective extraction of mixtures of polar and non-polar solvents.

A similar procedure is disclosed in British Patent No. 1,030,792, but instead of the initial esterification, the saponification of the free fatty acids with alkali is carried out. According to British Patent No. 774,855, the free fatty acids are first saponified with an alkali in an alcoholic medium, followed by acidification of the reaction mixture with a strong acid, separation of liberated glycerol, esterification, separation of volatiles by molecular distillation followed by preparation of the final product by molecular distillation at higher temperature. The process of DOS 31 26, 10 involves esterification of free fatty acids with a polyhydric alcohol, hydrogenation of unsaturated moieties, and separation of the non-tocopherol moiety by crystallization or separation of the mixture immediately after esterification by molecular distillation.

According to Japanese Patent Application Publication Nos. 55-137 185 β 53-116 71 · teceferol concentrates are prepared from deodorizing condensate only by molecular distillation, resulting in tocopherol concentrates having a content of 24 to 28% by weight. tocopherols and a large number of other accompanying substances. According to Japanese Application No. 57-144 200, free fatty acids are first esterified in deodorizing condensate, the reaction mixture is dissolved in a non-polar solvent, and the tocopherols are selectively adsorbed on a special type of silica gel.

These procedures have a number of drawbacks. In the catalytic esterification in the presence of a strong acid, unwanted by-products are formed, the action of alkali reduces the yield, in particular the yield of alpha-tocopherol. Distillation processes result in concentrates with a high content of accompanying substances. Some of the known methods are too complicated and not very suitable for practical use.

These disadvantages are overcome by the process for producing the tocopherol concentrate according to the invention. SUMMARY OF THE INVENTION The invention is based on the first step of removing the volatile constituents from the feedstock, which is preferably a deodorizing condensate, by vacuum distillation at a temperature of 180 to 220 ° C and a pressure of 10 to 100 Pa. In the next step, the distillate is obtained by molecular distillation at a temperature of 200 to 250 ° C and a pressure of 0.5 to 10 Pa. This is dissolved in an organic solvent such as a C 1 -C 5 aliphatic alcohol, a dialkyl ketone, a C 1 -C 2 chlorinated hydrocarbon, an acetic acid alkyl ester, a paraffinic hydrocarbon containing at least 6 carbon atoms, benzene or mixtures containing any of the abovementioned solvents or mixtures thereof with water, preferably in pure acetone. The resulting solution is gradually cooled to -1 to -30 ° C over a period of 2 to 24 hours, whereupon a crystalline fraction precipitates from the solution and is separated by filtration or centrifugation.

The solvent is distilled off from the mother liquor and the distillation residue is subjected to a second phase of vacuum distillation, in which the volatiles are removed from the mother liquor at a temperature of 170 to 230 ° C and a pressure of 0 to 100 Pa. In the second step, the final product is obtained at a temperature of 210 to 250 ° C and a pressure of 1 to 100 Pa as a distillate containing 45 to 60% by weight. tocopherols. The separated crystalline fraction is washed with an organic solvent, preferably acetone at a temperature of -1 to -30 ° C. The organic solvent is distilled off from the resulting wash solution and the distillation residue is added to the starting material or the wash solution is used to dissolve the distillate as a partial or complete replacement of the pure solvent.

The advantage of the process according to the invention lies in its relative simplicity and in the fact that no chemical changes to the tocopherols nor the formation of undesirable by-products occur during the process. The tocopherol concentrates having a sufficiently high content of natural tocopherols can be prepared by a process according to the invention on a commercially available apparatus and using available auxiliaries.

The production method is illustrated by the following examples.

Example 1

A two-stage molecular evaporator was fed a deodorizing condensate based on bezerukové rapeseed oil, which contained 5.5% by weight, at a feed rate of 100 kg per hour. tocopherols. In the first step the volatiles were removed at a temperature of 180-190 ° C and a pressure of 20-30 Pa. In a second step, a distillate was prepared at a temperature of 220-230 ° C and pressure

0.5 to 1 Pa. The distillate was dissolved in lots, 00 to 200 kg, in triple weight of acetone in an enamelled duplicate. The contents of the duplicate were gradually cooled to -18 ° C over 14 hours and the resulting crystalline portion was separated in portions on a vacuum filter. Each part of the adsorption of the crystalline fraction, i.e. 5 to 10 kg, with about 3 to 4 times a stream of acetone at a temperature of -18 to -20 ° C. Acetone was distilled off from the mother liquor in a conventional manner, the acetone residues were distilled off under vacuum in a film evaporator. The acetone from the wash solution was distilled off in the same manner but separately and the distillation residue was returned to the first phase of the vacuum distillation.

The distillation residue after mother liquor treatment was subjected to two-stage molecular distillation. In the first stage, the volatile paddle was distilled off at a temperature of 60 to 190 ° C and a pressure of 80 to 90 Pa. In a second step, a distillate was obtained at a temperature of 215 to 225 ° C and a pressure of 1 to 10 Pa containing 55.3% by weight. tocopherols, 3.4 wt. sterols,

5.8 fe. % of free fatty acids, the unsaponifiable fraction was 79.5% by weight. The yield of the final product, based on the raw material feed, was 6.4 ph.%, With a tocopherol yield of 64.4 ph.

Example 2

Deodorising condensate based on bezerukové rapeseed oil 3 containing 7.3 fe. the tocopherols were treated in a first stage in a film rotor evaporator at a temperature of 205 to 210 ° C and a pressure of 40 to 50 Pa and in a second stage in a molecular evaporator at a temperature of 230 to 235 ° C and a pressure of 2 to 4 Pa. The throughput at each distillation stage was 500 to 600 g / hour. 4.5 kg of distillate were then dissolved in 3 kg of acetone and the solution was cooled to -25 ° C over 24 hours, while the accompanying substances crystallized, which were filtered off in a conventional manner. They were then washed with acetone at -21 ° C.

Acetone was then distilled off from the mother liquor. The distillation residue was worked up in the first. vacuum distillation in a film rotor evaporator at a temperature of 220 to 225 ° C and a pressure of up to 65 Pa. In the second step, the distillate-final product was prepared, namely distillation in a molecular evaporator at a temperature of 210 to 215 ° C and a pressure of 10 to 15 Pa. The performance of the individual distillation stages was 500 to 600 g / hour, the final product contained 51.9% by weight. tocopherols. The yield of the final product, based on the starting material, was 7.2%. at a tocopherol yield of 51.2 lb.wt.

Example 3

Deodorizing condensate based on soybean oil containing 10.7 wt. the tocopherols were treated as described in Example 1. The final product obtained contained 55.9 wt. tocopherols. The yield of the final product relative to the starting material was 10.7 U > wt, with a tocopherol yield of 55.6 wt%.

Example 4

Deodorizing condensate based on sunflower oil containing 3.9% wt. The tocopherols were treated as described in Example 1 except that 200 kg of the preceding batch wash solution containing 160 kg of acetone and 40 kg of solutes were used to dissolve 30 kg of distillate. The concentrate obtained contained 48 wt. % of tocopherols, with a final product yield of 4.6 wt. and tocopherol yields 64 56 wt.

Example 5

20 wt. deodorant condensate of rapeseed oil and 80 wt. deodorizing condensate of soybean oil, which contained 5.5 wt. The tocopherols were treated as described in Example 1 except that the distillation residue after distillation of acetone from the mother liquor was distilled in a first stage in a rotor evaporator at a temperature of 210 to 215 ° C and a pressure of 50 to 60 Pa and in a second stage in the same evaporator at temperature 240 ° C and pressure 20 to 25 Pa. The concentrate contained 56% hmet. The total yield of the final product, based on the feedstock starting point, was 6.3% of the tactile, and that at a tefeferel yield of 64% of the tactile.

The process for producing the tocopherol concentrate of the present invention is particularly useful in the fat industry for processing by-products resulting from the production or further processing of vegetable oils. The concentrate itself is suitable as an additive for food and feed, for the preparation of dietetic products, as an antioxidant for oils and fats and as a starting product for the preparation of individual tocopherols and their derivatives.

Claims (3)

SUBJECT OF THE INVENTION A process for the production of a tocopherol concentrate by distillation and crystallization from by-products of the production and processing of vegetable oils, characterized in that the starting material is subjected to a two-stage distillation by removing in the first step volatiles at a temperature of 180-220 ° C and 10 up to 100 Pa and in the second stage a distillate is prepared by molecular distillation at a temperature of 200 to 250 ° C and a pressure of 0.5 to 10 Pa, which is then dissolved in acetone at 1 wt. part of the distillate is 1 to 5 wt. The resulting solution is gradually cooled to -1 to -30 ° C over a period of 2 to 24 hours, while the accompanying substances crystallize, which are then separated and washed with acetone at a temperature of -1 to -30 ° C, whereby the ha-weight of the mixture is reduced. 1 to 20 wt. parts of acetone, the mother liquor is distilled off and the distillation residue is subjected to two-stage distillation by removing the volatile fraction at a temperature of 170 to 230 ° C and a pressure of 10 to 100 Pa in a first stage, followed by a second stage at 210 to 250 ° C and a pressure of 1 to 100 Pa, preferably by molecular distillation, produces a distillate containing 45 to 60 wt. tocopherols. 2. A process as claimed in claim 1, wherein acetone is distilled off from the solution formed by washing the crystallized, separated accompanying substances and the distillation residue is added to the starting material, 3. A process according to claim 1, wherein acetone is dissolved at least in part by dissolving the distillate with a solution resulting from the washing of the crystallized, separate accompanying substances, the solution thus prepared containing 1 wt. 1 to 5 wt. parts of acetone.