JP4091099B1 - Dry fractionation method, highly liquid palm oil and oil composition using the same - Google Patents

Abstract

In a dry fractionation method of fats and oils, fats and oils having a high iodine value are efficiently obtained by crystallization in a short time. SOLUTION: A dry fractionation method using palm fractionated oil or its transesterified oil as a raw material fat. The ratio of trisaturated triglyceride to triglyceride in the oil / fat composition containing fat is 1.5% by weight to 3.5% by weight, and the ratio of dipalmitin monostearin to the trisaturated triglyceride contained in the oil / fat composition is The oil and fat composition is blended and dissolved so as to be 20% by weight or more, and after the step, the dissolved oil and fat composition is crystallized and separated into a crystalline fraction and a liquid fraction. Obtaining a liquid fraction having a value of 66 or more.
[Selection figure] None

Description

  TECHNICAL FIELD The present invention relates to a dry separation method for fats and oils, and a high liquid palm oil and fat composition using the same.

  Palm oil and its fractionated oil have long been used for frying oil, margarine, shortening, cacao substitute fat and the like. Palm oil can diversify its fields of use and functions by multi-stage separation. Recently, palm oil production has increased significantly, and research is being conducted to use it more highly.

  Palm oil fractionation methods are roughly classified into a solvent fractionation method using a solvent and a dry fractionation method not using a solvent in order to improve fractionation (fractionation) accuracy. Among these, the solvent fractionation method has a high fractionation accuracy but has problems in terms of cost and the like. For this reason, the dry fractionation method is often used today.

  However, the dry fractionation method has room for improvement in terms of improving the separation accuracy. This tendency becomes stronger as the amount of slurry crystallized during crystallization increases. In particular, palm olein is used as a raw material, so-called palm super olein having a iodine value (hereinafter also referred to as IV) of 64 or more and soft palm mid fraction (hereinafter referred to as soft PMF). This is noticeable when sorting.

Here, the reason why the separation accuracy is lowered in the dry fractionation method is that the viscosity of the slurry during crystallization is increased. As a result, the liquid fraction remains in the crystal fraction after filtration, and the separation accuracy is lowered.
Therefore, in the dry fractionation method, it is required to improve the fractionation accuracy even when the amount of crystals in the slurry is large, and to efficiently obtain fats and oils having a high iodine value by crystallization in a short time.

  By the way, palm fractionated oil having an iodine value of 64 or more is a category of oil and fat called palm super olein as described above. Palm super olein having a high iodine value is excellent in cold resistance and has high industrial utility value. Palm super olein having an iodine value of 66 or more is particularly excellent in cold resistance and hardly solidifies even at low temperatures.

  When obtaining palm super olein by fractionation using palm olein as a raw material, it is maintained at a temperature 1-15 ° C. lower than the melting point of palm olein to produce crystals, and the crystals are slowly grown to increase the separation accuracy. Is a common method. For this reason, it takes time for the first crystal generation, and in order to improve the fractionation efficiency without increasing the viscosity of the slurry, it takes a very long time for crystallization, which is not efficient. Moreover, the iodine value of the liquid fraction obtained by this method is less than 66, and it was difficult to obtain a liquid fraction having an iodine value of 66 or more.

As techniques for solving these problems in fractionation of palm oil, there are those described in Patent Documents 1 to 4.
Patent Document 1 describes a method for fractionating fats and oils that promotes crystallization by sonication when producing seed crystals.
In Patent Document 2, in order to reduce the viscosity at the time of filtration for the mixed fraction of the middle melting point component and the low melting point component of palm oil, after the first cooling, a palm oil low melting point part is further blended. A method of performing the next cooling is described.
Patent Document 3 describes that in a dry fractionation method for non-lauric oil such as palm oil, an oil lump is prepared by cooling and then pulverized and filtered into a slurry that can be pumped. Yes.

Patent Document 4 describes the following as a method for separating palm oil. That is, palm oil having an iodine value of 53 is heated to 60 ° C., then cooled to 45 ° C., and then β crystals of the coagulated palm fraction (stearin) are seeded at 45 ° C. The resulting suspension is gradually cooled to 30 ° C. and then filtered under a specific pressure cycle. Thereby, a transparent liquid fraction having an iodine value of 56 to 56.5 and a coagulation fraction having an iodine value of 22 to 24 are collected. Further, the obtained liquid fraction was heated to 45 ° C. to inoculate β ′ crystals, and the obtained suspension was cooled to 26-27 ° C. for 10 hours, then cooled to 18 ° C. in 8 hours, and further 18 ° C. Crystallize for 4 days. By filtering this under a specific pressure cycle, a liquid fraction having an iodine value of 65 to 67 and a coagulation fraction having an iodine value of 36 to 38 are obtained.
JP 2002-226886 A JP-A 63-258994 JP-A-2-14290 JP-A-60-101197 Marc Kellens and three others, "Palm oil fractionation", European Journal of Lipid Science and Technology, 109 (2007), p.336-349

However, the techniques described in Patent Documents 1 to 4 have room for improvement in the following points.
In the method described in Patent Document 1, ultrasonic waves are applied to the entire system for 6 to 12 hours. For this reason, it is difficult to control the surface of the apparatus or prevent crystallization promotion and crystal refinement.

  In the method described in Patent Document 2, an equipment for cooling the low melting point portion is necessary, and it is difficult to determine the timing of blending, and the filtration capacity may be reduced.

  In the method described in Patent Document 3, since the size of one lot that can be crushed is limited, the processing capacity is lowered and it cannot be said that the method is efficient.

  Moreover, in the method described in Patent Document 4, in order to obtain a fraction having a high iodine value, a crystallization time exceeding 4 days is required, which is not efficient.

  This invention is made | formed in view of the said situation, and provides the technique which obtains oil and fat with a high iodine number efficiently by crystallization of a short time in the dry-type fractionation method of fats and oils.

  According to the study of the present invention, in fractionation of palm oil, for example, to obtain a fraction having a high iodine value from palm olein having an iodine value of about 54 to 60, that is, super olein, the amount of crystals in the slurry is increased. There is a need. However, in the dry fractionation method, when the amount of crystals in the slurry is increased, the viscosity increases and the fluidity tends to decrease. Moreover, when fluidity | liquidity falls, since a filtration characteristic falls and the increase rate of a crystal amount becomes slow, there existed a case where fractionation efficiency fell.

  Therefore, as a result of further examination of a method for efficiently obtaining super olein, the present inventor made the total amount of trisaturated triglyceride in the oil and fat composition containing the raw material fat and oil 1.5% by weight to 3.5% by weight, In addition, by making dipalmitine monostearin (P2S) in tri-saturated triglyceride 20% by weight or more, the crystal growth rate does not become slow and the efficiency is high, and the viscosity of the slurry is low even when the amount of crystals increases. The yield after filtration was found to be high.

According to the present invention,
A dry fractionation method using palm fractionated oil or its transesterified oil as a raw oil and fat,
The ratio of the trisaturated triglyceride to the triglyceride in the oil / fat composition containing the raw oil / fat is 1.5% by weight to 3.5% by weight, and the dipalmitin mono to the trisaturated triglyceride contained in the oil / fat composition. Blending and dissolving the oil composition so that the proportion of stearin is 20% by weight or more;
After the step, crystallizing the dissolved oil and fat composition, separating the crystal fraction and the liquid fraction to obtain the liquid fraction having an iodine value of 66 or more;
A dry fractionation method is provided, including

  In the present invention, since the ratio of trisaturated triglyceride in the raw material fat is 1.5% by weight or more, initial crystallization is facilitated. In addition, when the amount of trisaturated triglyceride is too large, the number of crystals tends to be excessive during crystallization. When the number of crystals increases too much, the viscosity of the slurry tends to increase. However, by adjusting the ratio of trisaturated triglyceride in the raw oil and fat to 3.5% by weight or less, the slurry can be separated to the extent that there is no problem. An increase in viscosity can be suppressed.

  In addition, the inventors have found that the molecular species in the tri-saturated triglyceride affects the viscosity increase of the slurry with respect to the tri-saturated triglyceride content. And it discovered that the viscosity rise of a slurry was suppressed effectively by making dipalmitine monostearin (P2S) into 20 weight% or more in trisaturated triglyceride.

  As described above, in the fractionation method for obtaining a liquid fraction having an iodine value of 66 or more from palm fractionated oil or its transesterified oil, the ratio of trisaturated triglyceride to triglyceride contained in the oil / fat composition containing raw oil / fat is 1.5. The oil and fat composition is blended so that the ratio of dipalmitine monostearin to trisaturated triglyceride is 20% by weight or more, and the raw materials are dissolved, followed by crystallization. As a result, an increase in the viscosity of the slurry can be suppressed, so that the separation accuracy into the crystal fraction and the liquid fraction can be improved. For this reason, the crystallization time can be shortened, and a super olein having a high iodine value and excellent cold resistance can be obtained.

Further, it is possible to pre-Symbol obtain dry fractionation method by the lever, that such know the liquid fraction highly liquid of palm oil of the present invention.
Also, the according to the dry fractionation process of the present invention, it is also possible to obtain the high liquid resistance palm oil alone or oil composition obtained by mixing with other liquid oils.
By using the high liquid palm oil in the present invention, the cooling resistance is improved. Moreover, heat resistance improves. Therefore, it lasts longer than normal salad oil mainly composed of rapeseed oil, and from the viewpoint of environment, considering waste oil treatment and the like.

  It should be noted that any combination of these components, or a conversion of the expression of the present invention between a method, an apparatus, and the like is also effective as an aspect of the present invention.

  According to the present invention, fats and oils having a high iodine value can be efficiently obtained by crystallization in a short time by a dry fractionation method.

  Hereinafter, embodiments of the present invention will be described. In the description of the present specification, S means stearic acid, P means palmitic acid, and O means oleic acid. PSP is a triglyceride composed of palmitic acid at positions 1 and 3 and stearic acid at position 2, and PPS is a triglyceride composed of palmitic acid at positions 1 and 2 and stearic acid at positions 3 and 2 and 3. It includes both triglycerides in which the position is palmitic acid and the 1 position is stearic acid. PSP and PPS are collectively referred to as P2S (dipalmitin monostearin).

The dry fractionation method in the present invention uses palm fractionated oil or its transesterified oil as a raw oil and fat, and includes the following steps.
Step 1: The ratio of the trisaturated triglyceride to the triglyceride in the oil / fat composition containing the raw oil / fat is 1.5% by weight to 3.5% by weight, and the dipalmitin mono to the trisaturated triglyceride contained in the oil / fat composition A step of blending and dissolving the oil and fat composition so that the proportion of stearin is 20% by weight or more.
Step 2: A step of obtaining a liquid fraction having an iodine value of 66 or more by crystallizing the dissolved oil composition after Step 1 and separating it into a crystal fraction and a liquid fraction.
Hereinafter, each process will be described in detail.

The raw material fat used in Step 1 is palm fractionated oil or transesterified oil thereof, and includes, for example, palm olein obtained by one or more fractionations.
Moreover, as a raw material contained in an oil-fat composition, you may use palm-type fats and oils alone, or may mix and use with other fats and oils. However, in the present invention, a fraction having a high iodine value can be obtained from a palm-based oil / fat raw material without mixing other high-liquid oil / fat. Therefore, when palm fats and oils occupy most of the raw material, for example, when palm fats and oils are used alone or substantially alone, or when the mixing ratio of other fats and oils is 10% by mass or less, The effect of the present invention becomes remarkable.

  The iodine value of the fractionated palm oil or the transesterified oil used as the raw material fat is, for example, 54 or more and 60 or less. More specifically, palm olein having an iodine value of 55 or more and 58 or less is used as the fractionated palm oil or its transesterified oil. Moreover, as raw material fats and oils, a palm olein having an iodine value of 55 or more and 58 or less and a palm super olein having an iodine value of 65 or more may be used in combination.

  In Step 1, the ratio of trisaturated triglyceride to triglyceride in the oil and fat composition is 1.5% by weight or more and 3.5% by weight or less, and dipalmitin monostearin with respect to trisaturated triglyceride contained in the oil and fat composition. The oil and fat composition is blended so that the ratio is 20% by weight or more. By setting both the ratio of saturated triglyceride and the ratio of dipalmitine monostearin in the above ranges, a liquid fraction having an iodine value of 66 or more can be obtained easily and stably by crystallization in a short time.

It is possible to control the number of crystals at the time of crystallization by controlling the ratio of trisaturated triglyceride to triglyceride in the oil and fat composition.
When the ratio of trisaturated triglyceride is too small, the number of crystals is small, the total crystal surface area of the crystal and the liquid part is small, the rate of crystal increase is slow, and the efficiency of crystallization is lowered. For this reason, from the viewpoint of ease of initial crystallization, the ratio of trisaturated triglyceride is set to 1.5% by weight or more, preferably 1.7% by weight or more.
On the other hand, when the amount of trisaturated triglyceride is too large, the number of crystals becomes too large, and the viscosity of the slurry tends to increase. For this reason, from the viewpoint of suppressing an increase in the viscosity of the slurry, the ratio of trisaturated triglyceride is 3.5% by weight or less, preferably 2.5% by weight or less. When the proportion of trisaturated triglyceride is 3.5% by weight or less, the increase in viscosity can be suppressed to the extent that it does not interfere with separation. When the amount of trisaturated triglyceride exceeds 3.5% by weight, the number of crystals tends to be excessive. When the number of crystals increases too much, the viscosity of the slurry tends to increase.

  The ratio of dipalmitine monostearin (P2S) to trisaturated triglyceride contained in the oil / fat composition is 20% by weight or more, preferably 25% by weight or more, from the viewpoint of suppressing an increase in the viscosity of the slurry. The upper limit of the ratio of dipalmitine monostearin to trisaturated triglyceride is not particularly limited, and is specifically 100% by weight or less, but may be, for example, 70% by weight or less from the viewpoint of more easily preparing the oil and fat composition. .

  By the way, dipalmitin monostearin is hardly contained in palm oil, palm fractionated oil and its transesterified oil. For this reason, fats and oils containing dipalmitin monostearin are blended in the fat and oil composition.

  Oils and fats rich in dipalmitin monostearin do not exist in nature, but are prepared by a predetermined method. Although there is no special restriction | limiting about the preparation method of dipalmitin monostearin, For example, it can obtain by fractionating, isolate | separating, and refine | purifying after transesterification of a tristearin and palmitic acid.

  Further, in order to obtain an oil and fat containing dipalmitine monostearin more economically, it can be obtained by hydrogenating dipalmitine monounsaturated triglyceride. As a raw material of dipalmitine monounsaturated triglyceride, for example, palm oil, palm fractionated oil, and transesterified oil thereof can be used. By hydrogenating this, oils and fats containing dipalmitin monostearin are obtained. The higher the content of dipalmitine monostearin in the fats and oils to be blended in the fat and oil composition, the higher the dipalmitin monostearin content can be achieved with a smaller blending amount.

  More specifically, the oil and fat composition can be blended with an extremely hardened oil (very hard oil) of palm mid fraction. Here, the extremely hardened oil refers to oil obtained by using palm mid fraction as a raw material and hydrogenating until the iodine value is 3 or less and the melting point is 50 ° C. or more. The palm mid fraction has a very high content of dipalmitin monounsaturated triglyceride, and above all, a high content of PSP. Therefore, an extremely hardened oil having a dipalmitine monostearin content of, for example, about 55 to 80% by weight can be obtained by hydrogenating the palm mid fraction.

  By blending the fat and oil obtained by hydrogenating the palm mid fraction and the blended oil thereof into the raw material, the dipalmitin monostearin content can be more easily increased with a small blending amount. Further, from the viewpoint of increasing the dipalmitine monostearin content with a small addition amount, the ratio of dipalmitin monostearin in the extremely hardened oil is, for example, 55% by weight or more, preferably 60% by weight or more, more preferably 65% by weight or more. To do. In addition, although there is no restriction | limiting in particular in the upper limit of the ratio of the dipalmitine monostearin in extremely hardened oil, From a viewpoint which simplifies the preparation process of extremely hardened oil, it is 85 weight% or less, for example, Preferably it is 75 weight% or less. .

  Next, a method for dissolving the fat composition blended in Step 1 will be described. Although there is no restriction | limiting in particular in the melt | dissolution method, For example, an oil-fat composition is heated to predetermined temperature. Although heating temperature can be set according to the iodine number etc. of raw material fats and oils, for example, when palm olein with the iodine number of 50 or more and 60 or less is used as raw material fats and oils, you may heat to about 60-80 degreeC.

Next, step 2 will be described.
In step 2, the dissolved oil / fat composition is cooled to a predetermined temperature for crystallization, and separated into a crystal fraction and a liquid fraction.

  The cooling method is not particularly limited, but the initial crystal nucleation cooling temperature is preferably, for example, 14 ° C. or more and 25 ° C. or less from the viewpoint of obtaining an appropriate number of crystal nuclei. Further, the initial nucleation temperature is preferably a temperature close to the initial crystal growth temperature. From this viewpoint, the initial nucleation temperature is more preferably around 16 ° C. from the degree of supersaturation of palm olein (POP).

  As for the temperature after the initial crystallization, it is desirable to cool the oil and fat so that the supersaturation degree of the disaturated monounsaturated triglyceride represented by dipalmitine monoolein is kept at an appropriate value. If the degree of supersaturation is too large, new crystal nuclei are generated, which causes an increase in viscosity. If the degree of supersaturation is too small, the crystallization rate becomes slow, which is not efficient.

  According to the method of the present invention, for example, in fractionation of palm fraction oil or transesterified oil having an iodine value of about 54 to 60, the crystallization time when obtaining a liquid fraction having an iodine value of 66 or more is preferably 40 hours or less, preferably Can be shortened to 20 hours or less, and a liquid fraction having an iodine value of 66 or more can be efficiently obtained (for example, at a yield of 50% or more).

  After crystallization, it is separated into a crystalline fraction and a liquid fraction by filtration. The filtration method is not particularly limited, and for example, a belt press method, a filter press method, or the like can be used.

  By performing the fractionation in the procedure of Steps 1 and 2, the viscosity of the slurry after crystallization can be kept low, for example, below 3000 cp, so that the separation accuracy when separating into a crystal fraction and a liquid fraction is improved. be able to. In addition, the crystallization time can be shortened. The iodine value of the highly liquid palm oil (super olein) obtained by fractionation is as high as 66 or more, and it is excellent in cold resistance. Here, the iodine value is an index indicating the amount of unsaturated bonds. The higher the iodine value, the higher the amount of unsaturated fatty acid, and the higher the liquidity, which is preferable. Although there is no restriction | limiting in particular in the upper limit of an iodine value, it is set to 140 or less from a viewpoint of oxidation stability, for example.

In addition, although the detailed mechanism about the effect of dipalmitin monostearin is unknown, the following is guessed.
That is, in the fractionation in which a liquid fraction having an iodine value of 66 or more is obtained from palm oil, its fractionated oil, and transesterified oil, the main triglyceride species to crystallize is a disaturated monounsaturated triglyceride. Its main component is dipalmitin monoolein.

  In crystallization, first, trisaturated triglycerides initially form crystal nuclei, and disaturated monounsaturated triglycerides crystallize in these nuclei. The main component of trisaturated triglycerides in both palm oil and its fractionated and transesterified oils is tripalmitin. Tripalmitin produces the most stable crystals in the β form. On the other hand, when the palm fractionated oil and its transesterified oil are crystallized, the polymorph of the crystal often grows with β ′. Tripalmitin crystallizes β 'in the initial crystallization. However, it is thought that a part is crystallized with β. Most of the crystals are β 'in the long-term crystallinity. However, it can be considered that an unstable system is formed when β crystals are partially mixed. Therefore, it is considered that a solid phase transition is likely to occur due to a part thereof.

  Due to the solid phase transition, the degree of supersaturation increases rapidly even at the same temperature and concentration. As a result, new nuclei are generated, and the viscosity tends to increase thereafter. Further, due to the solid phase transition and rapid crystallization, the crystal surface loses order, and the crystal speed becomes slow as the degree of supersaturation decreases. Or, due to the solid phase transition (β '→ β), the crystal phase change occurs, and it grows not only in the spherical crystal but also in the flat upper rod-like crystal, and the viscosity may be increased by the flat or rod-like crystal. .

  In addition, it is considered that dipalmitin monoolein that crystallizes β ′ is difficult to crystallize in the β-form nucleus of tripalmitin. When the number is large and grows slightly, and the crystal size reaches a certain level, it is considered that the viscosity increases. Further, since the crystals are still small, they may pass through the filter pores during filtration and be mixed into the olein portion. That is, tripalmitin may be mixed into the olein part. Since tripalmitin has a high melting point, even if a small amount is mixed in the olein portion, it affects cold resistance, and there is a concern that cold resistance may deteriorate.

  If crystallization of tripalmitin to β form can be controlled, polymorphic transition and viscosity increase are considered to be suppressed. In this regard, crystals of dipalmitine monostearin (eg, 1,3-palmitine 2-stearin) are stable at β ′, and tripalmitin is compatible with dipalmitin monostearin (eg, 1,3-palmitine 2-stearin). (Non-patent document 1), tripalmitin does not reach β due to the presence of a certain amount of dipalmitine monostearin (for example, 1,3-palmitine 2-stearate), and polymorphic transition and increase in viscosity are suppressed. it is conceivable that.

  From the above estimation mechanism, it is inferred that the more dipalmitine monostearin in the tri-saturated triglyceride, the more stable β ′ initial crystals are generated.

  By the method of the present invention, for example, a liquid fraction having an iodine value of 67 or more and a crystal fraction having an iodine value of 38 or more and 52 or less can be obtained.

Further, for example, a crystal fraction having an iodine value of 38 or more and 47 or less can be obtained by the method of the present invention.
Here, the fraction having an iodine value of 38 or more and 47 or less is classified as soft PMF. With regard to soft PMF, from the viewpoint of a raw material for cacao substitute fat, it is desired that the content of 1.3 di-saturated-2 olein such as 1.3-dipalmitin-2 olein is high and the contamination of the liquid fraction is small. However, by performing the classification in the procedures of Steps 1 and 2, the classification accuracy can be improved from the viewpoint of the classification of the soft PMF.

  The highly liquid palm oil obtained as a liquid fraction by the method of the present invention has high liquidity and very high cooling resistance. In addition, compared with conventional rapeseed oil or soybean oil-based salad oil, the oil and fat composition prepared by blending the high-liquid palm oil of the present invention with high blending is excellent in heat resistance, for example when used in frying oil. Also last longer. In addition, rapeseed oil is expected to increase in price due to the spread of biodiesel in the future, and the supply side is expected to be tight, but in the present invention, by using palm oil, a comparatively stable salad oil standard is provided on the supply side. It becomes possible to supply an oil and fat composition having cooling resistance that also clears.

  Moreover, in the highly liquid palm oil obtained by this invention, the ratio of the tripalmitin in the triglyceride contained in a liquid fraction may be less than 0.05 weight%. By carrying out like this, the cold resistance of highly liquid palm oil can be improved much more stably.

  As mentioned above, although embodiment of this invention was described, these are illustrations of this invention and various structures other than the above are also employable.

(Raw oil)
In the following Examples and Comparative Examples, the following fats and oils were used as palm olein as raw material fats and oils.
Palm olein A: RBD (re-deodorized product) IV56.4 Palm olein Palm olein B: IVBD 56.7 RBD palm olein

Moreover, in the following Examples and Comparative Examples, the following fats and oils were used as palm super olein as the raw material fats and oils.
Super olein of IV67.3: Examples 1-4, Comparative Examples 2, 3
Super olein of IV 65.8: Example 5
Super olein of IV66.5: Example 6

(Extremely hardened oil)
In the following examples and comparative examples, the following fats and oils were used as extremely hardened oils (extremely hard oils) to be blended in the fat and oil composition.
Palm oil very hard oil: Yokoseki Yushi Co., Ltd. (lot 6C051)
Hard PMF hard oil: Hard PMF (IV35) manufactured by Toyonen Lever Co., Ltd., decolorized and deodorized with a laboratory hydrogenation device (Tripalmitin)
A reagent manufactured by Wako Pure Chemical Industries, Ltd. was used.

Example 1
An oil and fat composition was prepared by blending 95 parts by weight of palm olein A, 5 parts by weight of palm super olein, and 1.8% by weight of palm oil hard oil. Iodination of the obtained oil and fat composition (raw material) was 56.3.

  After the obtained oil and fat composition was dissolved at 70 ° C., crystallization was performed for 15 hours. During crystallization, after stirring and crystallization at an initial crystallization temperature of 18 ° C. for 2 hours, the water temperature was gradually lowered to a final water temperature of 9 ° C. The crystallization conditions and the final viscosity after crystallization are shown in Table 2.

  And the slurry after crystallization was filtered, and the liquid fraction and the crystal | crystallization fraction were isolate | separated. When filtering, a 25 mm-thick pilot filter was used, and fractionation was performed by pressurizing to 15 bar. The filtration time was 45 minutes.

  By filtration, a liquid fraction of iodinated 67.3 (olein part: yield 54.3%) and a crystal fraction of iodine value 43.1 (stearin part: yield 45.7%) were obtained ( Table 2).

(Examples 2-6, Comparative Examples 1-3)
According to the method of Example 1, an oil and fat composition was prepared, dissolved, crystallized, and then filtered off.

  Table 1 shows the blending of fats and oils in each Example and Comparative Example. Table 2 shows the crystallization conditions of each Example and Comparative Example, and the evaluation results of the oily fraction and the crystalline fraction obtained with the final viscosity of the oil and fat composition after crystallization. As shown in Table 2, Comparative Example 3 was cooled more slowly than Examples 1 to 6 and Comparative Examples 1 and 2, and crystallization was performed with a crystallization time of 23 hours. Table 3 shows the tripalmitin content (% by weight relative to TG) of the olein portion. In addition, the weight ratio of trisaturated triglyceride to triglyceride (trisaturated TG / TG (% by weight)) and fats and oils in the fats and oils compositions of Examples and Comparative Examples (described as “raw material” in Tables 1 and 2). FIG. 1 shows the relationship between the weight ratio of dipalmitine monostearin to trisaturated triglyceride in the composition (P2S / trisaturated TG (% by weight)).

From Table 2, all the liquid fractions obtained in each Example had an iodine value exceeding 67.
From Table 3, tripalmitin in the olein part was less than 0.05% in Examples 1 to 6 and Comparative Examples 1 and 2, and 0.08% in Comparative Example 3.

  FIG. 2 is a graph showing the relationship between the content of dipalmitin monostearin and the iodine value of the liquid fraction with respect to trisaturated triglyceride contained in the oil and fat composition in each Example and Comparative Example. As shown in FIG. 2, the iodine value of the liquid fraction increases as the content of P2S with respect to the trisaturated triglyceride contained in the oil and fat composition increases, and in the region where the content of dipalmitin monostearin is 20% by weight or more, The iodine value is 66 or more.

  In the above Examples and Comparative Examples, iodine, viscosity, and TG (triglyceride) were measured by the following methods.

(Iodine number)
About 0.2 g of a sample was measured in a mayonnaise bottle, dissolved in 10 ml of cyclohexane, 25 ml of Wisse solution was added thereto, and stored in the dark for 30 minutes. Thereafter, 20 ml of a 10 w / v% potassium iodide solution and 100 ml of water were added, and measurement was performed with a titrant (0.1 mol / L sodium thiosulfate standard solution). For the measurement, 736GP Titrino (potentiometric method) manufactured by Metonome was used.

(Viscosity of slurry)
Using a B-type viscometer (manufactured by TOKIMEC), rotor No. 3. The value after 1 minute at 12 rpm was measured.

(TG and tripalmitin content)
A. O. C. S. (The American Oil Chemists' Society) According to Official Method Ce 5-86, the column was long and measured by a highly accurate method. Specifically, 10 mg of a sample was placed in a GC (gas chromatography) vial and 1 ml of hexane was added and dissolved. GC analysis of the obtained sample was performed. The analysis conditions are shown below.
GC / FID (flame ionization detector): HP6890 (manufactured by Agilent Technologies)
Column: CP-TAP CB for Triglycerides, 25m × 0.25mm, df = 0.1
Temperature rising condition: 200 ° C. (1 min) → (5 ° C./min)→350° C. (10 min)
Inlet temperature: 350 ° C
Detector temperature: 365 ° C
Carrier gas: He gas Carrier gas flow rate: 1.7 ml / min
Make-up gas flow rate: 40ml / min
Hydrogen gas flow rate: 30ml / min
Air flow rate: 400ml / min
Split ratio: 1:50
Injection volume: 1 μl

(Cooling test of oil and fat composition)
About the thing which mix | blended 70 weight% and 30 mass% of rapeseed oil with the liquid fraction obtained in Examples 1-6 and Comparative Examples 1-3, and the obtained liquid fraction independently, the cooling test of salad oil specification ( 0 ° C., 5.5 h). A part of the cooling test result is shown in FIG.

  In Examples 1 to 6, all of the IV fractions were 67 or more liquid fractions, which were slightly crystallized to a fluid gel, and were transparent in a mixture with rapeseed oil.

  On the other hand, in Comparative Examples 1 and 2, IV was 64 and 65.3, respectively, and the liquid fraction alone solidified completely, and the mixture with rapeseed oil was cloudy.

Also in Comparative Example 3, the yield of the liquid part was 48.2%, which is 50% or less, and the yield of the liquid part was poor. As a result of the cooling test, the liquid fraction alone solidified completely and was turbid in the mixture with rapeseed oil, although it was IV66.2 and IV66 or higher. Moreover, although IV was higher than Comparative Examples 1 and 2, the time required for solidifying the liquid part alone was short.
From these, the liquid fraction obtained in each example has a higher iodine value than that of the comparative example, the tripalmitin content is less than 0.05%, and the cold resistance is improved. I understand.

It is a figure which shows the relationship between the weight ratio of the trisaturated triglyceride with respect to the triglyceride in the oil-fat composition in an Example, and the weight ratio of dipalmitin monostearin with respect to the tri-saturated triglyceride in an oil-and-fat composition. It is a figure which shows the relationship between the content of the dipalmitine monostearin with respect to the tri saturated triglyceride contained in the oil-fat composition in an Example, and the iodine value of a liquid fraction. It is a figure which shows the cooling test result in an Example.

Claims (6)

A dry fractionation method using palm fractionated oil or its transesterified oil as a raw oil and fat,
The ratio of the trisaturated triglyceride to the triglyceride in the oil / fat composition containing the raw oil / fat is 1.5% by weight to 3.5% by weight, and the dipalmitin mono to the trisaturated triglyceride contained in the oil / fat composition. Blending and dissolving the oil composition so that the proportion of stearin is 20% by weight or more;
After the step, crystallizing the dissolved oil and fat composition, separating the crystal fraction and the liquid fraction to obtain the liquid fraction having an iodine value of 66 or more;
Including dry fractionation.   The dry fractionation method according to claim 1, wherein the oil / fat composition is blended with an extremely hardened oil of palm mid fraction. In the dry fractionation method according to claim 2,
The dry fractionation method, wherein the proportion of dipalmitin monostearin in the extremely hardened oil is 55% by weight or more.   The dry fractionation method according to claim 3, wherein the iodine value of the raw material fat is 54 or more and 60 or less.   The dry fractionation method according to claim 4, wherein in the step of obtaining a liquid fraction, the crystal fraction having an iodine value of 38 or more and 47 or less is obtained. A highly liquid palm oil comprising a liquid fraction obtained by the dry fractionation method according to any one of claims 1 to 5 , wherein the proportion of tripalmitin in the triglyceride contained in the liquid fraction is 0.05% by weight. High liquid palm oil which is less than.