JPH0116832B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing tocopherol concentrates from distillates etc. produced as by-products in the deodorizing process of fats and oils. α, β, γ and -etcopherols (hereinafter referred to as tocopherols) are soybean oil,
Deodorizing scum, deodorizing sludge, Hotwell oil soapstock, etc. (hereinafter referred to as deodorizing distillate), which are by-products in the deodorizing process of rapeseed oil, cottonseed oil, safflower oil, rice bran oil, corn oil, sunflower oil, etc., usually contain about 1 to
It contains 20% and is a substance useful as vitamin E or antioxidant in foods, medicines, feeds, etc. However, in addition to tocopherols, hydrocarbons, sterins, glycerides, free fatty acids, etc. coexist in this deodorized distillate, making it difficult to use it directly for the above-mentioned purposes, and it is necessary to refine it to a purity that can be used for these purposes. Conventionally, this has required methods such as molecular distillation or ion exchange resin treatment. However, it is very difficult to obtain a concentrate with a tocopherol content of 60% or more in good yield using molecular distillation, and ion-exchange resin treatment requires column operation, which requires fairly sophisticated techniques for preparative separation. In addition, there are drawbacks such as the need to consider how to dispose of the mixed solvent that occurs when solvent replacement is performed. Another option is to use silica gel, but conventional crushed silica gel treatment has the same drawbacks as ion exchange resins. An object of the present invention is to obtain tocopherols from deodorized distillates and the like using simpler operations than conventional methods with good workability and high yield. As a result of various studies, the present inventors have found that tocopherol concentrates with extremely high concentrations can be produced in good yields by first esterifying free fatty acids in deodorized distillates with alcohol and then adsorbing them onto a specific silica gel. It has been found that the above objectives are achieved. The present invention has been completed based on this knowledge, and the present invention has been completed by adding alcohol to deodorized distillate by-produced in the deodorizing process of fats and oils or tocopherol-containing products obtained by concentrating these to obtain the deodorized distillate or After esterifying the free fatty acids in the tocopherol-containing material and performing concentration treatment if necessary, it is dissolved in a non-polar solvent and treated with spherical silica gel having an average pore diameter of 70 to 100 Å to select the tocopherols in the silica gel. This is a method for producing a tocopherol concentrate, which is characterized in that the tocopherols are adsorbed on the silica gel and then extracted from the silica gel using a polar solvent. The above-mentioned deodorizing distillate refers to deodorizing scum, deodorizing sludge, Hotwell soapstock, etc., which are produced as by-products in the deodorizing process of fats and oils such as soybean oil, rapeseed oil, safflower oil, rice bran oil, corn oil, and sunflower oil. Alternatively, the above deodorized distillate may be subjected to a distillation operation such as molecular distillation or steam distillation, a fractionation operation such as solvent fractionation, and an adsorption operation using silica gel, etc., and concentrated to be used as a starting material. You can also do it. Since the free fatty acids contained in these are adsorbed together with tocopherols on silica gel, tocopherols cannot be concentrated. Therefore, in the present invention, this free fatty acid is esterified with alcohol to prevent its adsorption onto silica gel, and as described later, it can also be removed by distillation, fractionation, etc. after esterification. Examples of the alcohol used include monohydric alcohols such as methanol and ethanol, polyhydric alcohols such as ethylene glycol, polyethylene glycol, propylene glycol, glycerin, erythritol, and pentaerythritol, and dehydrated condensates thereof. The appropriate amount of these alcohols to be added is about 1.1 times the acid value equivalent of the deodorized distillate. Esterification is carried out by a conventional method, whereby free fatty acids in the deodorized distillate react with the alcohol to produce an esterified product. After esterification, concentration treatment may be performed if necessary. For the concentration treatment, the above-mentioned distillation, fractionation, and adsorption operations performed on the deodorized distillate can be employed. Next, the obtained esterified product such as deodorized distillate is dissolved in 3 to 30 times the amount, preferably 5 to 20 times the amount of a non-polar solvent, and treated with silica gel. Examples of the nonpolar solvent used include hydrocarbon solvents such as petroleum ether, hexane, heptane, isooctane, and pentane, and mixed solvents thereof. Silica gel is spherical and has an average pore diameter of 70~
It must be 100 Å thick. Silica gels or crushed silica gels with average pore diameters outside this range have very low tocopherol concentrate yields and tocopherol contents, as shown in the Examples. After silica gel is activated at 100 to 150°C, it is made into a slurry form, or the esterified product is treated with a column, but since column operation requires advanced technology, a method in which it is made into a slurry form is preferred. In this method, silica gel in an amount of 1 to 10 times the amount of the esterified product is made into a slurry with the above-mentioned non-polar solvent, and the slurry is added to a solution of the esterified product in the non-polar solvent and stirred, so that the tocopherols are adsorbed onto the silica gel. This method is easy to operate, requires less silica gel for the object to be treated, and can be efficiently treated. Next, the solvent was removed to obtain silica gel with tocopherols adsorbed thereto, 5 to 30 times the volume of polar solvent was added thereto, stirring was performed at room temperature, the tocopherols adsorbed on the silica gel were extracted, and the tocopherols in the extract were A tocopherol concentrate is obtained by removing the polar solvent by distillation. The above polar solvents include diethyl ether and methanol, ethanol, n-propanol,
Examples include alcohols such as isopropanol, n-butanol, and isobutanol, ketones such as acetone, methyl isobutyl ketone, and methyl ethyl ketone, water, and mixtures thereof. The present invention is carried out in the manner described above, and according to this method, it is possible to obtain a concentrate with a high tocopherol content in a high yield with a simple operation compared to the conventional method, so it is extremely meaningful industrially. It is. Examples are shown below. Example 1 Soybean oil deodorized distillate [tocopherol content 19.4
% (according to the Emily Engel method; the same applies hereinafter), acid value 68.8, saponification value 133] Weighed 1000 g into a four-necked flask, added 1.1 times the acid value equivalent (41.4 g) of glycerin, and refluxed the xylol. The esterification reaction was carried out at 240°C. The reaction was terminated when the acid value became 0.5 or less, and the solvent was removed to obtain 1005 g of esterified product of deodorized soybean distillate.The obtained esterified product of soybean deodorized distillate was further subjected to conventional steam distillation. A distillate was obtained under the condition of 3 Torr (Table 1).

[Table] Distillate 2 of Table 1 (tocopherol content 52.6
Weigh out 20g of %), add 200g of hexane to dissolve it, add 60g of various silica gels slurried with 100g of hexane, and mix at room temperature.
The tocopherols were adsorbed onto the silica gel by stirring for a period of time. Furthermore, after sufficiently removing hexane, 200 g of ethanol was added to the tocopherol-adsorbing silica gel, and the tocopherols were extracted by stirring at room temperature for 1 hour, followed by solvent removal to obtain a tocopherol concentrate (Table 1). 2).

[Table] Example 2 Cottonseed oil deodorized distillate (tocopherol content 9.1%,
Acid value 75.4, saponification value 136) 1000g was weighed into a four-necked flask, 1.1 times the acid value equivalent (45.4g) of glycerin was added, and the esterification reaction was carried out at 180-230℃ under xyol reflux. Ivy. The reaction was terminated when the acid value reached 0.8, and the solvent was removed to obtain an esterified product of deodorized distillate of cottonseed oil. The above esterified product
20g each was weighed out and a tocopherol concentrate was obtained in the same manner as in Example 1 (Table 3).

【table】

Claims (1)

[Claims] 1 Alcohol is added to the deodorized distillate produced as a by-product in the deodorizing process of fats and oils or the tocopherol-containing material obtained by concentrating these to esterify the free fatty acids in the deodorized distillate or tocopherol-containing material, and the necessary After concentration treatment according to the conditions, the tocopherols are dissolved in a non-polar solvent and treated with spherical silica gel having an average pore diameter of 70 to 100 Å to selectively adsorb the tocopherols on the silica gel, and then the tocopherols are dissolved in a polar solvent. A method for producing a tocopherol concentrate, which comprises extracting it from the silica gel.