JPS6121993B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an improved method for solvent fractional crystallization of oil lipids. More specifically, the present invention relates to a method for fractionating high-quality fractionated oils and fats suitable for edible oils and fats for confectionery, such as cocoa butter substitutes and hard stearin butter, at a high yield. Oils and lipids, such as natural triglycerides, gum substances contained in trace amounts, phospholipids, other unsaponifiable substances, and synthetic glycerides (hereinafter simply referred to as fats and oils)
The solvent fractional crystallization method is an indispensable and important processing method as one of the effective utilization methods of fats and oils.
Improving the yield and quality has great industrial benefits, increases the utility value of the product, and allows the product to be supplied advantageously. An area of particular interest in the application of solvent fractional crystallization is the production of cocoa butter substitutes and hard stearin butter. The cocoa butter substitute referred to here refers to a normal tempering-type thiokolate fat that can partially or completely replace natural cocoa butter, and is desired to have melting properties equivalent to cocoa butter and a high substitution rate. Hard stearin butter refers to non-tempering edible fats and fats mainly used for sandwich biscuits and confectionery fillings, and includes lauric oils and fats such as coconut oil, which have a sharp melting property at temperatures close to body temperature. Hydrogenated fats and oils, hydrogenated vegetable fats, and their fractionated fats and oils are used. Methods that have already been proposed in the known solvent fractional crystallization method include proposals for organic solvents with good selectivity that can accurately separate the cocoa butter substitute fat fraction, and oleodistearin and oleopalmy, which are triglyceride components of cocoa butter. tostearin,
There are many proposals regarding the selection and fractionation method of raw material fats and oils from which monounsaturated triglycerides such as oleodipalmitin can be fractionated, and chemical engineering methods such as methods for crystallizing oil and fat crystals and methods for separating crystals. Examples of selective solvents that have already been proposed are mainly ketone solvents such as acetone and methyl ethyl ketone, paraffinic hydrocarbons such as n-hexane, their chlorinated and nitrated products, and acetic acids such as ethyl acetate, methyl acetate, and isopropyl acetate. They are esters. The use of most of these ketone solvents, paraffin solvents, and acetate esters as food additives is restricted or prohibited. Furthermore, those that are recognized as natural products or food additives also have insufficient selectivity, and there is a desire for a safer and more selective solvent. In order to satisfy these demands, the present inventor conducted research on improving the solvent fractional crystallization method using various organic solvents or their mixed solvents, and unexpectedly found that aliphatic monohydric alcohols, which had been conventionally considered to be non-selective solvents, The present invention was completed by discovering that some of these exhibit selectivity that is significantly superior to conventional selective solvents such as ketone, paraffin, and acetate esters. To explain the method of the present invention, oleostearin type fats and oils, such as shea butter, Malabar fat, similar fats and their slightly hydrogenated oils, palmitic fats and oils, such as palm oil, beef tallow, fulwara fat, Borneo fat, Iritzpe fat, and similar fats and oils. Oils and fats containing the monounsaturated triglyceride, which is the triglyceride component of cacao butter, such as fats and their slightly hydrogenated oils, such as mixed oils and fats of oleostearin type oils and palmitic oils, have 4 carbon atoms.
After dissolving in the aliphatic monohydric alcohol of 1 to 8, it is cooled or subjected to a solvent fractionation method without cooling to separate crystalline triglyceride and liquid triglyceride fractions. For example, to obtain cacao fat substitute, the main component is monounsaturated triglyceride, which has a melting point of 27~
Separate the medium melting point portion at 38℃. The intermediate melting point part here does not necessarily refer to the intermediate fraction among the three fractions; in the case of shea butter, etc., a small amount of high melting point saturated triglycerides may be removed or not removed to form the primary crystal part or secondary crystal part. It also includes the intermediate melting point fraction that is separated as In addition, trans monomers obtained by curing polyunsaturated triglycerides such as erucic acid type oils and fats such as rapeseed oil, mustard oil, and similar fats, and oleic-linole type oils and fats such as soybean oil, safflower oil, rice bran oil, and similar fats. A hydrogenated oil having an unsaturated fatty acid content of 20 to 80% is subjected to the solvent fractional crystallization method in the same manner as above to separate a desired fraction. For example, in the method of fractionating monounsaturated triglyceride and the intermediate melting point part with increased trans acid content, the primary crystals obtained by removing the slightly remaining liquid or soft part or the unexpectedly produced high melting point saturated triglyceride It also includes a part, a primary liquid part, and a secondary crystal part. The aliphatic monohydric alcohol having 4 to 8 carbon atoms, such as butyl alcohol, hexyl alcohol, octyl alcohol, etc., and isomers and mixtures thereof, particularly preferably butyl alcohol or a mixed solvent thereof, can be prepared by the above-mentioned solvent fractional crystallization method. Melting points obtained as secondary crystal part, primary liquid part, and secondary crystal part
The fractionation accuracy of the intermediate melting point region of 27 to 38℃ is significantly improved, that is, the intermediate melting point region by the solvent fractional crystallization method using an aliphatic monohydric alcohol having 4 to 8 carbon atoms is compared to conventional ketone, paraffin, and acetate ester systems. Compared to the method using a solvent, the contamination of soft parts and hard parts other than the intermediate melting point part is significantly improved. The effect of this improvement is to prevent the softening of the intermediate melting point portion due to the inclusion of the soft portion, and to improve the tailing phenomenon in the high temperature portion of the melting curve of the intermediate melting point portion due to the inclusion of the hard portion, that is, poor melting in the mouth. Obtains sensitive melting properties similar to cocoa butter. It is difficult to obtain such an effect by the conventional solvent fractional crystallization method using a selective solvent, even if the yield of the intermediate melting point region is significantly sacrificed. This fact indicates that the selectivity of the solvent contributes more than the fractional yield of the intermediate melting point to the improvement of the melting characteristics of cocoa butter substitutes and hard stearin butter by the solvent fractional crystallization method. Further, it is clear from the examples below that the aliphatic monohydric alcohol of the present invention has superior selectivity to the degree of saturation and unsaturation of fatty acid groups in triglycerides compared to conventional solvents. The improvement of the mid-melting point portion of the present invention allows the cocoa butter substitute fat to be more freely substituted for natural cacao butter, and significantly improves the yield of the mid-melting point portion even in hard stearin butter. In addition, particularly excellent properties improve the melting point drop of the mixed fat and oil caused by mixing cocoa butter and cacao substitute fat, and minimize changes in the crystal form and crystal rearrangement mode of the mixed fat and oil. This is probably because the contamination of high melting point saturated triglycerides, especially tristearin and palmitodistearin, in the first fractionation into the intermediate melting point portion is improved, and the contamination of polyunsaturated triglycerides is prevented in the second fractionation. A further advantageous feature of the present invention is that it has excellent selectivity to unsaponifiable substances contained in raw material fats and oils, especially gum substances. That is, the inventors have discovered that the aliphatic monohydric alcohol of the present invention increases the difference in the dissolution temperature of triglycerides and gum substances in the solvent compared to conventional solvents. As a result, according to the method of the present invention, gum substances precipitate at the dissolution temperature (hereinafter simply referred to as dissolution temperature) of the high melting point triglyceride in the solvent, so that a fraction consisting only of gum substances and a liquid triglyceride fraction are separated in the dissolved state of triglyceride. It is now possible to separate triglycerides, which used to be mixed in gum at about 30 to 40%, and can be almost completely eliminated. The method of the present invention will be described in more detail: 1 part by weight of a raw material oil such as an oleostearin type oil, a palmitic oil, a hydrogenated vegetable oil containing a high trans acid content, and a carbon number of 4-
8 and 0.5 to 6 parts by weight of aliphatic monohydric alcohol are mixed and dissolved at a temperature equal to or higher than the melting temperature of fats and oils. In particular, the melting temperature of the gum material-containing fat or oil is 20 to 70°C, preferably 45 to 60°C. At temperatures below 60°C, the gum substance does not dissolve but precipitates, so only the gum substance containing almost no oil can be separated. When the temperature of the gum substance rises above 90°C, it begins to melt in the solvent and the gum crystals are fused together, and when the temperature exceeds 70°C, it becomes opaque and dissolves in the solvent and cannot be separated, requiring cooling and recrystallization. Furthermore, when the temperature is raised again to the melting temperature of fats and oils, separation becomes possible. However, if the crystal part is separated at the same time as the crystal part, there is no need to raise the temperature after cooling and recrystallization. The recrystallization temperature of gum is
15-20°C is suitable. Next, high melting point saturated triglyceride crystals are removed by primary fractionation, and the liquid portion is cooled again and secondary fractionation is performed to separate triglyceride crystals having a medium melting point of 27 to 38°C. This medium melting point portion is suitable as a cacao substitute fat or hard stearin butter depending on the type of raw material fat. The crystal morphology of the crystal part in the primary and secondary fractionation of the present invention is significantly more homogeneous and finer than that of conventional method solvents, but it has excellent transient properties, and this is compatible with the selectivity of saturated and unsaturated triglycerides of the present solvent. It is thought that the effect will be exerted over time. The solvent of the present invention can also contain 40% of ethyl alcohol, methyl alcohol, and propyl alcohol having less than 4 carbon atoms.
A moisture content of 10% or less is acceptable. A more detailed explanation will be given below using examples. Example 1 When 200g of purified shea butter containing 4.1% of unsaponifiable matter is melted and mixed with 800g of butanol and heated to 50°C, the triglyceride is completely dissolved in the butanol and the solution becomes completely transparent with gum substances in the solution. It precipitates and settles. Separately, 8.1 gr of gum material was removed. Then every minute while stirring the liquid part.
It was cooled to 35°C at a rate of 0.5°C and held for 30 minutes. This is then filtered to form high melting point triglyceride crystals.
I got 0.68gr. Further, this liquid portion was similarly cooled to -5°C, maintained as such for 30 minutes, and then filtered to obtain 150 gr of medium melting point triglyceride crystals. The obtained crystals were homogeneous crystals with a size of 20 to 40 mesh and had good transient properties. Next, Table 1 shows a comparison with fractionated oils obtained from the same raw material oil using acetone, firstly fractionated at 29°C, secondly fractionated at -5°C, and otherwise under the same conditions as in the Examples.

[Table] According to Table 1, the yield of the intermediate melting point portion was significantly improved,
Furthermore, the iodine value and melting point have been improved. Example 2 When a mixed oil of 110 gr of refined shea butter and 90 gr of refined palm oil was mixed with a mixed solvent of 640 gr of phthanol and 160 gr of ethanol and heated to 55°C, the triglycerides were completely dissolved and the mixture became completely transparent. Since the gum material precipitated in the solution, it was separated and 4 gr of gum material containing almost no oil was collected. Next, the liquid part was cooled down to 25°C at a rate of 0.5°C per minute while stirring, and kept as such for 30 minutes.
was overremoved. Further, this liquid portion was similarly stirred and cooled to 5° C. and maintained at that temperature for 30 minutes to precipitate and separate a homogeneous and fine medium-melting point crystal portion to obtain 125 gr of cocoa butter substitute fat. Next, for comparison, the yields of cocoa butter substitutes A and B were obtained from the same raw material fat using acetone at 24°C for the first fractionation and at -5°C for the second fractionation, and at 20°C for the first fractionation and at -5°C for the second fractionation. The ratio and characteristic values are shown in Table 2. Second
From the table, it can be seen that the acetone fractionation is inferior to the method of the present invention because the characteristic values do not change significantly even if the yield is sacrificed. In addition, the cooling curve in Figure 1, the cooling curve in Figure 2,
It is clear from the figure solid fat index that the quality of the cacao fat substitute according to the present invention is excellent.

[Table] Example 3 500g of mixed refined oil of 50% rapeseed oil and 50% soybean oil was hydrogenated using a nickel catalyst to obtain an iodine value of 73.7 melting point
A hydrogenated oil with a trans acid content of 42.5% was prepared at 33.0°C. 100g of this hardened oil was dissolved in 500g of butanol and fractionated at 25°C for the primary fractionation and 10°C for the secondary fractionation to obtain a medium melting point portion of 56gr. For comparison with this hard stearin butter, add 100g of hydrogenated oil to methyl ethyl ketone.
Dissolved in 500gr, primary fractionation at 25℃, secondary fractionation at 10℃,
A comparison is made between the hard stearin butter (A) that was fractionated at 22°C for the first fractionation and the hard stearin butter (B) that was fractionated at 7°C for the secondary fractionation with the hard stearin butter obtained by the method of the present invention. Shown in the table. From Table 3, it is clear that obtaining hard stearin butter with the same properties using conventional solvents is accompanied by a significant decrease in yield.

【table】

[Table] Example 4 Octyl alcohol 60%, methyl alcohol 40%
Dissolve 100gr of refined palm oil in 400gr of mixed solvent
Cool from 50°C to 21°C at a rate of 0.5°C per minute, hold for 30 minutes, and then filter to remove 8.5gr (oil) of the crystal part, then cool the liquid part to 5°C in the same way.
The medium melting point portion of 46.5 gr was separated after holding for 30 minutes. Table 4 shows a comparison of the characteristic values of this cacao substitute fat and the intermediate melting point fraction fractionated at the same yield using acetone as a solvent.

【table】

[Table] Example 5 200 g of purified palm was melted, mixed with 800 g of butanol, cooled from 50° C. to 27° C. at a rate of 0.5° C. per minute, kept as it was for 30 minutes, and then filtered. 57.5 g of the crystalline portion was removed from the solvent to obtain 20.8 g of high melting point portion. Furthermore, the liquid part was cooled to 5°C, held for 30 minutes, filtered, and 293.5 g of crystal part was removed from the solvent.
95.0g of the medium melting point part and the liquid part were desolvated to obtain 84.0g of the liquid oil part. Its yield balance and properties are shown in Table 5. In addition, separately, ethanol was used as Comparative Example 1, n-hexane was used as Comparative Example 2, and Comparative Example 3 was used.
Table 5 also shows the yield and characteristics obtained by carrying out the same operations as in Example 5 under the conditions shown in Table 5, using n-decanol as the compound.

【table】

[Table] From the Examples and Comparative Examples shown in Table 5, first of all, regarding the selective crystallization of butanol, based on the yield balance of the fractionated fat and its characteristics, the intermediate melting point part of the example has a yield of 47.5 % and an iodine value of 41.9, whereas Comparative Example 1 has a high iodine value and unselective crystal purity, and Comparative Example 2 has a low yield of the intermediate melting point region.
That is, the examples show that the medium melting point part of palm oil (disaturated monounsaturated glyceride fraction) suitable for cacao fat substitute can be obtained in good yield. This is thought to be due to the fact that the solubility of triglyceride in ethanol becomes very low at temperatures below 20°C, and on the contrary, hexane exhibits a large solubility even below 0°C. Furthermore, when economic efficiency is considered, it can be seen that ethanol fractionation is very disadvantageous in terms of the use of a large amount of solvent, and hexane fractionation is very disadvantageous in terms of cooling costs since the crystallization temperature is -20°C. In addition, the melting point of decanol (10 carbon atoms), which is a higher alcohol, is lower than the liquid melting point of palm oil, so selective crystallization is not possible, and its high viscosity means that it has poor separation properties. Its use as a solvent is disadvantageous.

[Brief explanation of the drawing]

FIG. 1 is a cooling curve of the cacao fat substitute of Example 2 of the present invention, natural cacao butter, and a comparative example, and FIG. 2 is a diagram comparing the solid fat index of the same.

Claims (1)

[Scope of Claims] 1. In the solvent fractional crystallization method of fats and oils, an aliphatic monohydric alcohol whose main component is one kind of aliphatic monohydric alcohol having 4 to 8 carbon atoms, or a mixed solvent of two or more kinds as a selective solvent. A method for solvent fractional crystallization of fats and oils, which is characterized by dissolving fats and oils in water and separating crystalline triglyceride and liquid triglyceride fractions. 2. The fractional crystallization method according to claim 1, wherein the aliphatic monohydric alcohol is butyl alcohol alone or a mixture containing butyl alcohol as a main component. 3. The fractional crystallization method according to claim 1 or 2, wherein the fractionated oil or fat in which the medium melting point portion having a melting point of 27 to 38°C is fractionated after removing the high melting point triglyceride portion is a cacao substitute fat. 4. Claim 1, wherein after removing the high melting point triglyceride portion, the fractionated oil and fat from which the middle melting point portion with a melting point of 27 to 38°C is fractionated is hard stearin butter.
The fractional crystallization method described in Section 1 or 2. 5. Claim 1, which includes the steps of removing a high melting point triglyceride portion from an oleodystearin fat and oil, and separating a middle melting point portion of 27 to 38° C. that is mainly composed of monounsaturated triglycerides; or The fractional crystallization method described in Section 2. 6. Claim 1 or 2 which includes the steps of removing a high melting point triglyceride part from palmitic oil and fat, and separating a middle melting point part with a melting point of 27 to 38 °C mainly composed of monounsaturated triglycerides. The fractional crystallization method described in Section 2. 7. A step of removing the high melting point triglyceride part from a mixed oil of 80 to 40 parts of oleodystearin oil and fat and 20 to 60 parts of palmitic oil, and removing the middle melting point part of the melting point of 27 to 38 °C, which is mainly composed of monounsaturated triglyceride. The fractional crystallization method according to claim 1 or 2, which comprises a step of fractionating. 8 Hydrogenated oil with a trans monounsaturated fatty acid content of 20 to 80% obtained by curing oleic-linole type fats is first fractionated to remove high melting point parts, and a second fractionation is performed to remove monounsaturated triglycerides and trans acid content. The fractional crystallization method according to claim 1 or 2, wherein the intermediate melting point portion having an increased melting point of 27 to 38° C. is fractionated.