Crystallization inhibitor for emulsifiers

Abstract

To provide a crystallization suppressor of an emulsifier capable of suppressing crystallization of an emulsifier added to a fat composition.SOLUTION: A crystallization suppressor for emulsifiers other than diglycerol oleate in fat compositions containing diglycerol oleate as an active ingredient. A method for suppressing crystallization of an emulsifier in the fat composition, comprising adding a diglycerol oleate to the fat composition containing an emulsifier other than diglycerol oleate. Diglycerol oleate is an esterification product of diglycerin and oleic acid, and is produced by a method known per se such as an esterification reaction.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a crystallization inhibitor for an emulsifier. [Background technology]

[0002] During storage of an oil or fat composition, the oil or fat components or other added components may crystallize and precipitate, which not only deteriorates the appearance of the oil or fat composition but also causes problems such as the components of the oil or fat composition becoming non-uniform and the quality being reduced.

[0003] To address these problems, a known method for inhibiting the crystallization of fats and oils in a fat and oil composition is, for example, a crystallization inhibitor for fats and oils comprising a polyglycerol fatty acid ester, characterized in that the constituent fatty acids of the polyglycerol fatty acid ester contain erucic acid and stearic acid (Patent Document 1). Also, a known method for inhibiting the crystallization of plant sterols added to a fat and oil composition is, for example, a crystallization inhibitor for plant sterols, characterized in that the constituent fatty acids are selected from two or more saturated and unsaturated fatty acids having 8 to 22 carbon atoms, and at least one of which is selected from unsaturated fatty acids (Patent Document 2).

[0004] In the above-mentioned methods, an emulsifier is added to the fat and oil composition to suppress crystallization of the fat and oil and other added components. However, since the emulsifier added to the fat and oil composition may crystallize, a new method that can replace these methods has been sought. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-124448 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-091523 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide an emulsifier crystallization inhibitor that can inhibit the crystallization of an emulsifier added to an oil or fat composition. [Means for solving the problem]

[0007] As a result of extensive research into the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by using diglycerol oleate, and have completed the present invention based on this finding.

[0008] That is, the present invention comprises the following (1) and (2). (1) A crystallization inhibitor for emulsifiers other than diglycerol oleate in an oil or fat composition, which contains diglycerol oleate as an active ingredient. (2) A method for inhibiting crystallization of an emulsifier in an oil or fat composition, which comprises adding diglycerol oleate to an oil or fat composition containing an emulsifier other than diglycerol oleate. [Effects of the Invention]

[0009] By adding the crystallization inhibitor for an emulsifier of the present invention to an oil or fat composition, crystallization of the emulsifier in the oil or fat composition can be inhibited. DETAILED DESCRIPTION OF THE INVENTION

[0010] The diglycerol oleate used in the present invention is an esterification product of diglycerol and oleic acid, and is produced by a method known per se, such as an esterification reaction.

[0011] The diglycerin constituting the diglycerin oleate may be a diglycerin mixture having an average degree of polymerization of 1.5 to 2.4, preferably 2.0, obtained by adding a small amount of acid or alkali as a catalyst to glycerin and then heating the mixture to a temperature of, for example, 180°C or higher under an atmosphere of an inert gas such as nitrogen or carbon dioxide to cause a polycondensation reaction. The diglycerin may also be obtained from glycidol, epichlorohydrin, or the like as a raw material. After the reaction is complete, treatments such as neutralization, desalting, and decolorization may be carried out, if necessary.

[0012] In the present invention, the diglycerin mixture is preferably purified by a method known per se, such as distillation or column chromatography, to obtain a high-purity diglycerin having a high concentration of diglycerin consisting of two glycerin molecules of 50% by mass or more, preferably 85% by mass or more.

[0013] A preferred method for producing the diglycerol oleate used in the present invention is outlined below. For example, a conventional reaction vessel equipped with a stirrer, a heating jacket, baffles, etc. is charged with diglycerol and oleic acid in a molar ratio of about 1:0.8 to 1:1.6, preferably about 1:1. Sodium hydroxide is added as a catalyst, and the mixture is stirred and mixed. The mixture is heated to a predetermined temperature under a nitrogen gas atmosphere while removing water produced by the esterification reaction from the system. The reaction temperature is typically in the range of 180 to 260°C, preferably 200 to 250°C. The reaction pressure is either reduced or normal pressure, and the reaction time is 0.5 to 15 hours, preferably 1 to 3 hours. The end point of the reaction is usually determined by measuring the acid value of the reaction mixture, with an acid value of 12 or less as a guide. The resulting reaction liquid is a mixture containing unreacted fatty acids, unreacted diglycerin, diglycerin monooleate, diglycerin dioleate, diglycerin trioleate, diglycerin tetraoleate, etc. After completion of the reaction, the resulting reaction liquid is cooled to 120°C or higher but lower than 180°C, preferably 130 to 150°C, and then an acid is added to neutralize the catalyst. The mixture is then left to stand preferably for 15 minutes to 1 hour, and if a polyol containing unreacted diglycerin separates into a lower layer, it is removed, and diglycerin oleate is obtained.

[0014] The diglycerol oleate typically has a monoester content of 30% by mass or more and less than 50% by mass, and it is preferable to obtain diglycerol monooleate by subjecting the diglycerol oleate to molecular distillation using, for example, a falling thin film molecular distillation apparatus or a centrifugal molecular distillation apparatus, or by purifying the diglycerol monooleate using a method known per se, such as column chromatography or liquid-liquid extraction.

[0015] As a diglycerol oleate, for example, Poem DO-100V (trade name: diglycerol monooleate; manufactured by Riken Vitamin Co., Ltd.) is commercially produced and sold, and this can be used in the present invention.

[0016] The crystallization inhibitor for an emulsifier of the present invention contains diglycerol oleate as an active ingredient and is added to an oil or fat composition containing an emulsifier other than diglycerol oleate, thereby inhibiting the crystallization of the emulsifier other than diglycerol oleate in the oil or fat composition.

[0017] As the crystallization inhibitor for an emulsifier of the present invention, the diglycerol oleate may be used as it is, or the ester may be mixed with any other ingredients to the extent that the objects and effects of the present invention are not impaired, and then formulated for use.

[0018] The oil and fat composition can be produced, for example, by mixing an edible oil and fat, an emulsifier other than diglycerol oleate, and a crystallization inhibitor for the emulsifier of the present invention, heating and dissolving the mixture to, for example, 60 to 90°C, and then cooling to room temperature.

[0019] The edible oils and fats are preferably edible animal or vegetable oils and fats, transesterified oils, fractionated oils, etc., which are liquid at room temperature (15 to 25°C). Examples of such oils and fats include safflower oil, soybean oil, cottonseed oil, rice oil, rapeseed oil, and olive oil. These oils and fats also include medium-chain triglycerides (MCTs), glycerin fatty acid diesters, and propylene glycol fatty acid diesters. These edible oils and fats may be used alone or in any combination of two or more.

[0020] The emulsifier other than the diglycerol oleate is preferably one that is relatively likely to crystallize over time in the edible fat or oil composition after being dissolved in the edible fat or oil to prepare the fat or oil composition, such as glycerol fatty acid esters, polyglycerol fatty acid esters (excluding diglycerol oleate), sucrose fatty acid esters, etc.

[0021] There are no particular restrictions on the contents of edible fats and oils, emulsifiers other than diglycerol oleate, and the crystallization inhibitor for the emulsifier of the present invention in 100% by mass of the above-mentioned fat and oil composition, but for example, the content of edible fats and oils is 60 to 98.9% by mass, preferably 70 to 97.8% by mass, the content of emulsifiers other than diglycerol oleate is 0.1 to 20% by mass, preferably 0.2 to 15% by mass, and the content of the crystallization inhibitor for the emulsifier of the present invention is 1.0 to 20% by mass, preferably 2.0 to 15% by mass.

[0022] The uses of the oil and fat composition are not particularly limited, but examples include improving the texture of foods such as noodles, cooked rice, side dishes, and soups, seasoning, and imparting bacteriostasis to these foods, with the use of imparting bacteriostasis to these foods being particularly preferred.

[0023] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. [Example]

[0024] [Preparation and evaluation of oil and fat compositions] (1) Raw materials 1) Rapeseed oil (manufactured by Boso Oil Co., Ltd.) 2) Glycerin monostearate (trade name: Emulgy MS; manufactured by Riken Vitamin Co., Ltd.) 3) Glycerin monolaurate (trade name: Poem M-300; manufactured by Riken Vitamin Co., Ltd.) 4) Glycerin monolinoleate (trade name: Emulgy MU; manufactured by Riken Vitamin Co., Ltd.) 5) Diglycerin monolaurate (trade name: Poem DL-100; manufactured by Riken Vitamin Co., Ltd.) 6) Triglycerin monopalmitate (trade name: Poem TRP-97RF; manufactured by Riken Vitamin Co., Ltd.) 7) Decaglycerin oleate (trade name: Poem J-0381V; manufactured by Riken Vitamin Co., Ltd.) 8) Sorbitan monostearate (trade name: Poem S-60V; manufactured by Riken Vitamin Co., Ltd.) 9) Diglycerin monooleate (trade name: Poem DO-100V; manufactured by Riken Vitamin Co., Ltd.)

[0025] (2) Preparation of oil and fat composition The emulsifiers were added to rapeseed oil heated to 60°C according to the blending ratios shown in Tables 1 and 2, and the mixture was stirred uniformly by hand for 1 minute using a spoon to obtain 100 g of each of oil and fat compositions 1 to 14. Of these, the preparations of oil and fat compositions 1 to 7 are examples according to the present invention, and the preparations of oil and fat compositions 8 to 14 are comparative examples.

[0026] [Table 1]

[0027] [Table 2]

[0028] (3) Confirmation test of the crystallization suppression effect of emulsifiers The oil and fat compositions 1 to 14 obtained in (2) were each placed in a transparent glass container, and after storing the container in a thermostatic bath at 20°C for two weeks, the presence or absence of precipitates or turbidity due to crystallization of the emulsifier was confirmed. Those that did not undergo crystallization of the emulsifier and maintained a clear state were evaluated as good (◯), and those that experienced crystallization of the emulsifier were evaluated as poor (×). The results are shown in Table 3.

[0029] [Table 3]

[0030] As is clear from the results in Table 3, the oil and fat compositions 1 to 7 obtained by adding diglycerol oleate were marked with "○" and showed that crystallization of the emulsifier was suppressed. In contrast, the oil and fat compositions 8 to 14, which did not contain diglycerol oleate, showed a mark of "×" and showed that crystallization of the emulsifier could not be suppressed.

Claims

1. The crystallization inhibitor for an emulsifier in an oil or fat composition contains 0.2 to 20 mass % of one or more emulsifiers selected from the group consisting of glycerol monostearate, glycerol monolaurate, polyglycerol fatty acid esters (excluding diglycerol oleate), and sorbitan monostearate, and contains diglycerol oleate as an active ingredient.

2. A method for inhibiting crystallization of an emulsifier in an oil or fat composition, comprising adding diglycerin oleate to the oil or fat composition containing 0.2 to 20 mass% of one or more emulsifiers selected from the group consisting of glycerin monostearate, glycerin monolaurate, polyglycerin fatty acid esters (excluding diglycerin oleate), and sorbitan monostearate.

Images