JP6967334B2 - Compositions Containing Polyunsaturated Fatty Acid Esters - Google Patents

Description

The present invention relates to polyunsaturated fatty acid or polyunsaturated fatty acid ester-containing compositions and foods containing the compositions, which are characterized by inhibiting and / or delaying the progress of oxidation of polyunsaturated fatty acids. For example, the composition of the present invention has a dissolved oxygen content of 1 mg / L or less, a peroxide value of 3 or less, an acid value of 1 or less and an anicidin value of 5 or less, and (for example, by adsorbent treatment). A mixture containing ethyl ester of ω3 highly unsaturated fatty acid from which peroxide has been removed, soybean phospholipid and vitamin E, and palmitate ascorbic acid and an emulsified mixture of egg yolk are further sprayed with a homogenized composition by adding egg white. The present invention relates to a composition containing an ω3 highly unsaturated fatty acid ethyl ester, which is dried by a drying method and whose water content is adjusted to 5 wt% or less, and a food containing the composition.

Ω3 polyunsaturated fatty acids such as ALA, SDA, EPA, DPA, and DHA contained in fish oil, algae, genetically modified plants, etc. or their ethyl esters can only improve cardiovascular disease, neurological function, and immune function. It is a material that exerts a wide range of functions such as prevention and improvement of diseases through suppression of oxidative stress, and is also effective in suppressing the growth of cancer, and its applications are continuing to expand (Non-Patent Documents 1 and 2, In addition, Patent Document 1).

These ω3 fatty acids are marketed as food materials, health food materials, cosmetic materials, and pharmaceutical materials as they are as glycerides, free fatty acids, or ethyl esters, or after being concentrated and purified. These ω3 fatty acids are generally concentrated by a timely combination of a vacuum precision distillation method, a molecular distillation method, a chromatographic method, a low temperature solvent fractional crystallization method, a urea addition method, a silver nitrate complex forming method, and the like (Patent Document 2).

In particular, the ethyl ester form of EPA (hereinafter referred to as EPA ethyl) has been launched as a switch OTC as a therapeutic agent for arteriosclerosis obliterans, hyperlipidemia, etc., and the market for pharmaceutical grade EPA ethyl continues to expand.

In addition, some are commercially available as glycerides as they are or after the ethyl ester is concentrated and purified. For example, when fish oil is used as a starting material, the ω3 fatty acid contained in the glyceride may be concentrated by a low temperature solvent fractional crystallization method or by an enzyme treatment such as lipase, but on a commercial scale, the ω3 fatty acid purity. Is limited to 70%.

A glyceride having an ω3 fatty acid purity of 90 wt% or more is synthesized by using the fatty acid having a purity of at least 90 wt% or a lower alcohol ester thereof as a starting material and using it as an ester with glycerin. The esterification reaction can generally be obtained by a reversible reaction with lipase or a chemical synthesis reaction with an acid or an alkali. The fatty acid of 90 wt% or more or a lower alcohol ester thereof can be obtained by a known method (Patent Documents 3 and 4).

That is, for example, in order to purify any one of the ω3 polyunsaturated fatty acids selected from ALA, SDA, EPA, DPA, DHA, etc. to a high purity of 70 wt% or more, the fatty acid or its lower alcohol ester is used. It is preferably in the form. Further, when a distillation facility is used, it is practical to concentrate and purify in the form of a lower alcohol ester instead of a free fatty acid because of the physical characteristics such as the facility and the boiling point of the fatty acid.

Further, in the case of a lower alcohol ester of a fatty acid, the ethyl ester is most desirable when it is assumed to be used in the fields of foods, pharmaceuticals, cosmetics and the like.

However, since the glycerides of these ω3 polyunsaturated fatty acids or free fatty acids and ethyl esters have 3 to 6 unsaturated bonds per molecule, the oxidation rate is high, and a very small amount of peroxide is used. The production is accompanied by a sufficiently unpleasant fishy odor. Many antioxidant technologies, fish odor removal technologies, and masking technologies have been proposed to solve the problems.

As for antioxidants, a large number of patent documents can be found, including a method in which vitamin E, ascorbic acid palmitate, and lecithin are used in combination (Patent Document 5), and a method in which a spice extract is used (Patent Documents 6 and 7). Regarding fish oil containing a large amount of ω3 highly unsaturated fatty acids, the synergistic antioxidant action of nitrogen-containing phospholipids such as phosphatidylcholine and phosphatidylethanolamine in soybean phospholipids against vitamin E (Non-Patent Document 3), ascorbic acid palmitate. Although its effectiveness (Patent Document 2) is known, neither method can completely prevent the progress of oxidation.

In order to improve the problems involved, a technique aiming at improving storage stability by reducing dissolved oxygen contained in vegetable oils and fats is known. That is, reduction of dissolved oxygen by adding hydroquinone to fats and oils (Non-Patent Document 4), flavor improvement method by substituting oxygen-containing dissolved gas in fats and oils with carbon dioxide (Patent Document 8), mayonnaise by substituting nitrogen gas, etc. A method for reducing dissolved oxygen in an oil-in-water emulsion and preventing deterioration of quality (Patent Document 9) is known and its effectiveness has been clarified.

Regardless of the presence or absence of the above steps for reducing dissolved oxygen, in general, polyunsaturated fatty acid-containing glyceride lipids and their ethyl esters, and ω3 polyunsaturated fatty acids such as ALA, SDA, EPA, DPA, and DHA. Lipids containing the ethyl ester of the above contain, for example, peroxides and decomposition products such as their alkyl radicals (L.) and peroxy radicals (LOO.) In the form of alcohols, ketones, aldehydes, acids and the like. It is necessary to remove the ester because it not only becomes an obstacle in sensory evaluation and nutrition, but also causes further deterioration of quality through, for example, induction of a chain reaction. Therefore, removal of peroxides and their decomposition products not only improves the sensory evaluation and nutritional value of the product, but also reduces the peroxide value (POV), acid value (AV), and anicidin value (AnV). It is valid.

The removal of lipid peroxides and their decomposition products in fats and oils is widely known. For example, a molecular distillation method (Patent Document 10), an adsorbent treatment method (Patent Document 2, Patent Document 11, Patent Document 12, and Patent Document 12) are known. Document 13) and the like are known, and any method can be used in the present invention. Experimentally, a method for removing lipid peroxide using a Florisil (100/200 mesh) column is known (Non-Patent Document 5).

Detection of lipid peroxide and its decomposition products is performed, for example, _{by thin layer chromatography (TLC) method using silica gel 60PF 254} TLC plate (Merk, 0.25 mm thickness), silicic acid column chromatography, high performance liquid chromatography. (HPLC) method and the like are known (Non-Patent Document 5). Further, for example, when qualitatively assayed by silica gel thin layer chromatography (TLC) using a developing solvent for neutral lipids (n-hexane / diethyl ether / acetic acid = 85/15/1), a peroxide near the origin is obtained. It is also known to perform a simple test based on the presence or absence of an object.

Many techniques such as steam distillation method, molecular distillation method, and silicic acid column chromatographic method are known as methods for deodorizing polyunsaturated fatty acid-containing fats and oils, but none of them is sufficient (Non-Patent Document 2).

Regarding the masking method, a method using a fat-soluble ginger flavor (Patent Document 14), a method using a spice extract (Patent Documents 6 and 7), a method using a citrus flavor or a yogurt flavor (Patent Document 15), and a Rakan fruit extract are used. Many other technologies such as the method to be used (Patent Document 16) have been published, and some of them have been confirmed to be effective, but the drawback is that their uses are limited depending on the type of flavor used for masking. ing.

In addition, since the fat and oil is liquid at room temperature, it is difficult to mix it with other raw materials in a normal process, it is difficult to package and transport it, and it develops a fishy odor-like offensive odor due to oxidation due to high contact frequency with oxygen. And so on, and its use in food is limited. In order to solve the problems, the technology related to powdering the fats and oils is open to the public.

That is, microencapsulation of DHA-containing fats and oils in yeast cells (Patent Document 17), microcapsules having a membrane using gelatin cured by transglutaminase (Patent Document 18), and emulsion powder containing monoglyceride. Many techniques are disclosed, such as chemical conversion (Patent Document 19), a method using defatted soybean as an excipient (Patent Document 20), and multi-layered microcapsules (Patent Document 21).

Further, as a technique for powdering fats and oils using egg yolk and egg white, a method using egg white as an excipient (Patent Documents 22 and 23) and a method using egg yolk (Patent Document 24) are known. Dried egg yolk usually contains about 25 wt% lipid, and the content of phospholipid is about 28 wt% (Non-Patent Document 6), but the highly unsaturated fatty acid ester of this product (particularly, ω3 type) There are no known powders that utilize the antioxidant activity against highly unsaturated fatty acid ethyl esters.

JP 2015-147770 JP 2015-63653 Japanese Patent Application Laid-Open No. 2000-21258 Japanese Patent Application Laid-Open No. 11-209786 JP-A-9-272892 JP-A-7-236418 JP-A-2007-16045 JP 2014-140332 JP-A-2005-110674 JP-A-2002-23398 Japanese Patent Application Laid-Open No. 7-188692 JP 2002-102692 Special table 2013-521004 Japanese Patent Application Laid-Open No. 06-189717 Japanese Patent Application Laid-Open No. 08-092587 JP 2012-223138 Japanese Patent Application Laid-Open No. 05-253464 Japanese Patent Application Laid-Open No. 05-292899 Japanese Patent Application Laid-Open No. 06-172782 Japanese Patent Application Laid-Open No. 07-313507 JP 2013-177400 Japanese Patent Application Laid-Open No. 63-44444 Japanese Patent Application Laid-Open No. 8-23881 Special table 2007-516711

Mitsumasa Mankura and Mitsu Kayama, Title "Physiological functions and utilization of AA, EPA, DHA", "AA, EPA, DHA-highly unsaturated fatty acids (co-authored)", edited by Mitsu Kayama, Koseisha Koseikaku, Tokyo, 1995 , Pp. 207-224 Mitsumasa Mankura, Koji Nishioka, Hideaki Kada, Tomoko Yamamoto, Nagao Totani, Toshio Nakamoto, Takao Kaneyuki, Fusako Takayama, Title "Development and Functional Evaluation of DHA Products", Japan Food Science, 49 (1) ), 45-52 (2010) Takeshi Segawa, Masazumi Kamada, Setsuko Hara, Yoichiro Totani, Title "Antioxidative Behavior of Phospholipids Against Polyunsaturated Fatty Acids in Fish Oil (3rd Report)", Oil Chemistry, 44 (1), 36-42 (1995) Shizo Hirano and Moriji Kurobe, Title "Quantification of Dissolved Oxygen in Oils and Fats and Effect on Dissolved Oxygen", Industrial Chemistry Magazine, 57 (9), 14-16 (1954). Junji Terao and Yukio Matsushita, Title "Isolation of Lipid Peroxide (Experimental Method of Lipid Peroxide", edited by Naoshi Kaneda and Nobuo Ueda), pp. 21-35, Ishiyaku Publications, Inc., Tokyo (1983) Keie Ito, Natsumi Yamanaka, Noriko Ogawa, Title "Comparison of phosphatidylcholine content in yolk of eggs laid by chickens of different chicken species", Bulletin of Gifu Women's University, 37, 15-18 (2008)

Despite the existence of the above-mentioned background technology, a technology for keeping the progress of oxidation in the process of commercialization and the progress of oxidation during the storage period of the product within the level at which the expression of offensive odor is not noticed by sensory evaluation has not yet been developed. Therefore, it is an object of the present invention to prevent and / or delay the progress of oxidation during the process of commercialization and the shelf life of the product. More specifically:
Ethyl esters of ω3 polyunsaturated fatty acids such as ALA, SDA, EPA, DPA, and DHA have a high oxidation rate, and the higher the purity, the higher the rate. Protecting mixtures containing ethyl esters of saturated fatty acids from oxidation has not been sufficiently accomplished by prior art and remains an unsolved technical challenge. In addition, the development of various decomposition products associated with oxidation, particularly an unpleasant oxidative odor accompanied by a fishy odor, is an unsolved technical problem. Therefore, it is important to block the oxidation progress of the ethyl ester and prevent the development of fishy odor, but the complete oxidation progress in view of the physical characteristics of highly unsaturated fatty acids having three or more unsaturated bonds. From the viewpoint that prevention and prevention of fishy odor development are unrealistic, in the present invention, the progress of oxidation during the process of commercialization and the storage period of the product is maintained within a level in which the development of offensive odor is not noticeable in terms of sensory evaluation. That is a technical issue.

Further, in order to solve the above technical problems, in the present invention, in order to facilitate the expansion of applications of ethyl esters of ω3 polyunsaturated fatty acids in the food field, polyunsaturated fatty acids are powders having excellent antioxidant properties. A composition containing a saturated fatty acid ethyl ester and a food containing the composition are provided.

The problem will be solved by providing a composition containing a highly unsaturated fatty acid ethyl ester, which is a powder having excellent antioxidant properties, and a food containing the composition.

The present inventors have a highly unsaturated fatty acid ester having a dissolved oxygen content of 1 mg / L or less, a peroxide value of 3 or less, an acid value of 1 or less, and an anisidin value of 5 or less (for example, ω3 high-unsaturated fatty acids). The above problem was solved by providing ethyl ester).

The invention also provides, for example:
(Item 1)
A composition comprising a highly unsaturated fatty acid or a highly unsaturated fatty acid ester, wherein the dissolved oxygen content is 1 mg / L or less, the peroxide value is 3 or less, and the acid value is 1 or less. A composition having an anicidin value of 5 or less.
(Item 2)
The composition according to item 1, further comprising an antioxidant.
(Item 3)
The composition according to item 1 or 2, further comprising an emulsifier.
(Item 4)
The composition according to item 2, wherein the antioxidant is selected from the group consisting of soybean phospholipids, vitamin E, and ascorbic acid palmitate.
(Item 5)
The composition according to item 3, wherein the emulsifier is selected from the group consisting of egg yolk and egg white.
(Item 6)
The composition according to item 1, which is a spray-dried product having a water content of 5 wt% or less.
(Item 7)
A food product comprising the composition according to item 1.
(Item 8)
The composition according to item 1, which contains 40 wt% to 99 wt% of an ester of a highly unsaturated fatty acid selected from the group consisting of α-linolenic acid, stearidonic acid, eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid.
(Item 9)
The composition according to item 1, wherein the total content of the polyunsaturated fatty acid ester in the composition is 20 wt% to 60 wt%.
(Item 10)
The composition according to item 1, wherein the highly unsaturated fatty acid or highly unsaturated fatty acid ester is an adsorbent-treated highly unsaturated fatty acid or highly unsaturated fatty acid ester.
(Item 11)
A food containing 5 wt% to 50 wt% of the composition according to item 1 in terms of solid matter.
(Item 12)
The food according to item 11, which is selected from the group consisting of breads, noodles, confectionery, oil and fat foods such as plants, soy protein foods, miso, dairy products, meat products, egg products, fish paste products, and instant foods. ..

The present invention also provides, for example, a highly unsaturated fatty acid ester having a dissolved oxygen content of 1 mg / L or less, a peroxide value of 3 or less, an acid value of 1 or less, and an anisidin value of 5 or less (for example, ω3 high unsaturated fatty acids). Ethyl ester), a mixture containing soybean phospholipids and vitamin E and ascorbic acid palmitate, and an emulsified mixture of egg yolks, and egg whites were added and homogenized, and the homogenized composition was dried by a spray drying method to reduce the water content to 5 wt%. Provided are a composition containing an ω3 highly unsaturated fatty acid ethyl ester, which is a powder prepared below, and a food containing the composition.

(Definition of terms)
The following is a list of definitions of terms specifically used herein.

As used herein, the term "polyunsaturated fatty acid" means an unsaturated fatty acid having 16 or more carbon atoms and having two or more double bonds in the molecule, and is typically docosahexaenoic acid. Ethyl esters of omega-3 fatty acids such as (DHA) can be mentioned. Examples of polyunsaturated fatty acids include docosahexaenoic acid (C22: 6, DHA), eicosapentaenoic acid (C20: 5, EPA), arachidonic acid (C20: 4, AA), and docosapentaenoic acid (C22: 5, DPA). ), Stearidonic acid (C18: 4, SDA), α-linolenic acid (C18: 3, ALA), linoleic acid (C18: 2) and the like, but are not limited thereto. The derivative of the highly unsaturated fatty acid obtained by the acquisition method of the present invention means that the fatty acid is not a free type, for example, an ester type derivative such as a methyl ester or an ethyl ester of a highly unsaturated fatty acid, or an amide such as an amide or a methyl amide. Examples include, but are not limited to, type derivatives, fatty alcohol type derivatives, triglycerides, diglycerides, monoglycerides and the like. Preferably, the target substance of the purification method of the present invention is selected from the group consisting of docosapentaenoic acid, eicosapentaenoic acid, and docosahexaenoic acid, and ethyl esters with their lower alcohols (eg, methanol and ethanol). Ethyl ester. Preferably, the polyunsaturated fatty acid or polyunsaturated fatty acid ester of the present invention is contained in the final purified oil in an amount of 50 wt% to 95 wt%.

As used herein, the term "acid value" is an index of carboxylic acid contained in a fatty acid and is a mg of potassium hydroxide required to neutralize the free fatty acid contained in 1 g of the sample. Say a number. The acid value measurement method is as described in the 2003 version of the standard oil and fat analysis test method (edited by the Japan Oil Chemists' Society).

The term "peroxide value" used herein is not directly related to "acid value". Peroxide value is used interchangeably with "POV" and represents the amount of peroxide, which is the primary product produced in the early stages of autoxidation of fats and oils. When a peroxide is present in the mixture (raw material fat), the peroxide is unstable and decomposes to produce an aldehyde. Since aldehydes are generally toxic, it is also important to control the generation of aldehydes. The "peroxide value (POV)" can be measured by reacting potassium iodide with a sample and titrating the iodine liberated from potassium iodide by hydroperoxide in the fat. More details are as described in the 2003 version of the standard oil and fat analysis test method (edited by the Japan Oil Chemists' Society).

As used herein, the term "antioxidant" refers to a substance that attenuates or eliminates harmful reactions involving oxygen in living organisms, foods, daily necessities, and industrial raw materials. Typically, antioxidants include, but are not limited to, tocopherol, ascorbic acid palmitate, lecithin, catechin, and rosemary extract, and butylhydroxytoluene.

The method for measuring the fatty acid composition analysis method used in the present specification is well known, and is as described in, for example, the 2003 version of the standard oil and fat analysis test method (edited by the Japan Oil Chemists' Society).

As used herein, the term "vacuum precision distillation method" refers to a method of separation using the difference in boiling points of each component. For example, in the case of EPA, the component having 20 carbon chains including EPA is located at an intermediate boiling point among fish oil fatty acids, and in the case of the batch type, it is possible to use a single-column distillation apparatus in the case of continuous distillation. , A two-tower device or a four-tower device is required. In the case of a two-tower system, the components (initial distillate) of C19 or less are distilled off, the residual amount is sent to the second tower, and the C20 component (main distillate) is separated for purification.

The term "fixed layer chromatography method" used in the present specification is a method in which a column is filled with a filler and a raw material is passed through an eluent to take out a fraction containing a target component, and concentrate and purify the fraction. say. Preferred fillers include, but are not limited to, silica gel, reverse phase silica gel, and silver nitrate impregnated silica gel.

As used herein, the term "SMB chromatography" is a separation method that utilizes the principles of liquid chromatography, with different selective adsorptions of a particular component in a raw material and another particular component. A movement in which a plurality of unit-filled layers filled with a capable adsorbent are connected in series, and a unit-filled layer in the most downstream part and a unit-filled layer in the most upstream part are connected to form an endless circulation system. Chromatography using layers. As used herein, "SMB chromatography" is used interchangeably with "pseudo-moving layer chromatography."

As used herein, the term "wintering treatment" is used interchangeably with "dewaxing" to keep fats and oils at specified low temperatures for extended periods of time to provide fats and oils with a high melting point (eg, glycerides or acylglycerols). The process of precipitation.

Examples of the adsorbent used in the present invention include one or more combinations selected from adsorbents such as activated carbon, activated clay, acid clay, silicic acid (silica), silica gel, alumina, and magnesium oxide. Not limited to. Since unsaturated fatty acid ethyl esters such as EPA ethyl ester and DHA ethyl ester that have been concentrated and purified by adsorbent treatment contain impurities such as lipid peroxides, coloring components, and foreign substances derived from raw materials generated during purification. Based on a well-known method, the adsorbent is treated with one or more combinations selected from adsorbents such as activated charcoal, activated clay, acidic clay, silicic acid (silica), silica gel, alumina, and magnesium oxide. For example, the adsorbent treatment can reduce the POV to 3 or less, preferably 1 or less (ie, the POV can be reduced by removing impurities including lipid peroxides).

As used herein, the term "anisidine valence" refers to a method of colorimetrically quantifying a carbonyl compound. Use p-anisidine for color development. Since the operation is simpler than the carbonyl value (CV), it is used in EU countries as a method for evaluating the degree of deterioration of frying oil. However, since the intensity of color development differs depending on the type of carbonyl compound (presence or absence of double bond and number of carbon atoms), it is not possible to compare fats and oils having different fatty acid compositions.

As used herein, the term "esterification" refers to the reaction of esterifying a fatty acid in the presence of a lower alcohol. Methods of esterifying fatty acids are well known in the art. For example, a method of esterifying a fatty acid using a lower alcohol in the presence of an acid catalyst is well known as an acid catalyst method, and a method of esterifying a fatty acid using a lower alcohol in the presence of an alkali catalyst is well known as an alkali catalyst method. Yes (edited by the Japan Oil Chemists' Society, 4th Edition Oil and Fat Chemistry Handbook, Maruzen (Tokyo), 2001, pp. 454-456; Mitsuo Okahara et al., Hydrolysis, Esterification and Ester Exchange, Revised 3rd Edition Oil and Fat Chemistry Handbook (Japan) Esterification Society), Maruzen (Tokyo) 388-389 (1990)). Ethyl esterification of fatty acids using an enzyme such as lipase is also well known as an enzymatic method (Japanese Patent Laid-Open No. 2006-288228). In the present invention, two or more esterification methods may be combined, if necessary. Preferably, the first esterification is carried out by an acid-catalyzed method or an enzymatic method, and then the esterification is carried out by an alkali-catalyzed method. Esterification using ethanol is called ethyl esterification.

As used herein, the term "antioxidant" refers to any substance that prevents and / or suppresses oxidation. The antioxidant of the present invention is preferably kept within a level at which the development of fish oil-specific fishy odor, unpleasant fishy odor-like offensive odor, etc., which accompanies the progress of oxidation during the manufacturing process or product storage, is not noticeable. It is possible.

Examples of the antioxidant include, but are not limited to, vitamin E and soybean phospholipids and ascorbic acid palmitate as its sinargists. Vitamin E uses synthetic vitamin E (dl-α-tocopherol), natural vitamin E (d-α-tocopherol), and a mixture of natural α-, β-, γ-, and δ-tocopherol (mixed tocopherol). Although it is possible, mixed tocopherols are most preferable in consideration of economic efficiency and comparison of antioxidant activity with respect to price. The addition amount is preferably 0.01 to 3 wt% with respect to the ω3 polyunsaturated fatty acid ethyl ester, but is most preferably 0.05 to 1.0 wt% in consideration of economic efficiency.

As soybean phospholipids, paste (liquid) products containing about 60 wt% of phospholipids and powder products containing about 95% wt% of phospholipids are generally known. Further, fractionated products obtained by concentrating and purifying any of phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol and the like, which are the main components constituting soybean phospholipids, are also known. In the present invention, both paste (liquid) products and powder products can be used. For fractionated products, phosphatidylcholine and phosphatidylethanolamine are available. In either case, regardless of the shape of the product, the amount added as a phospholipid is preferably 0.1 to 10 wt% with respect to the ω3 polyunsaturated fatty acid ethyl ester, but the sensory evaluation associated with the addition of phospholipids. Considering the deterioration of quality, 1 to 8.0 wt% is the most desirable. When soybean phospholipids are used, synergistic effectiveness with the phospholipids contained in the egg yolk used in the present invention is also expected.

Since ascorbic acid palmitate is expected to have a synergistic antioxidant effect with vitamin E, in the present invention, the addition amount is preferably 0.01 to 1 wt% with respect to the ω3 polyunsaturated fatty acid ethyl ester. Considering the solubility in fats and oils, 0.05 to 0.1 wt% is the most desirable.

As used herein, the term "emulsifier" refers to any substance that emulsifies polyunsaturated fatty acids or polyunsaturated fatty acid esters. Examples of the emulsifier of the present invention include, but are not limited to, chicken egg products such as egg yolk and / or egg white.

The present invention makes it possible to prevent and / or delay the progress of oxidation during the process of commercialization and the shelf life of the product. For example, according to the present invention, there is provided a technique for keeping the progress of oxidation in the process of commercialization and the progress of oxidation during the storage period of a product within a level at which the appearance of offensive odor is not noticed by sensory evaluation.

Hereinafter, the present invention will be described. Throughout the specification, it should be understood that the singular representation also includes its plural concept, unless otherwise noted. It should also be understood that the terms used herein are used in the sense commonly used in the art unless otherwise noted. Accordingly, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, this specification (including definitions) takes precedence. Also, in the present specification, "wt%" is used interchangeably with "mass fraction concentration".

(Preparation of polyunsaturated fatty acid ester)
Since the highly unsaturated fatty acid ester of the present invention is a mixture of a plurality of types of fatty acid esters, generally, a method such as a vacuum precision distillation method, a molecular distillation method, a chromatographic method, a urea addition method, a silver nitrate complex method, or a low temperature solvent fractionated crystal method is used. It is possible to obtain a mixture containing at least 95 wt% or more of the target ω3 fatty acid by combining and purifying one or more of them (Patent Document 8). As a matter of course, since these purification methods themselves are for illustration purposes only and not the object of the present invention, the esterification method and the concentration purification method itself are not limited.

In general, fish oils such as ray liver oil and squid liver oil, which have a high content of highly unsaturated fatty acids and a high iodine value, have a dissolved oxygen content of 1.4 mg / L and 5.7 mg / L, respectively, and are ordinary vegetable oils such as soybean oil. It is said that the amount of dissolved oxygen in the above is lower than 7.6 mg / L (Non-Patent Document 4, Patent Document 9). It is understood that this is because fish oil, which contains a large amount of polyunsaturated fatty acids, consumes oxygen at a higher rate than vegetable oil and exceeds the rate at which oxygen is dissolved from the air. Since the ω3 polyunsaturated fatty acid ethyl ester having a high degree of unsaturation is used in the present invention, it is presumed that most of the dissolved oxygen exists as a peroxide or a decomposition product thereof.

The ω3 polyunsaturated fatty acid ethyl ester absorbs a large amount of dissolved oxygen in the process from the stage of raw raw fats and oils to ethyl esterification, and exists as a peroxide or its decomposition product. It causes the development of fish oil-specific fishy odors and unpleasant offensive odors during the powdering process and storage period. Therefore, the ω3 highly unsaturated fatty acid ethyl ester, which has absorbed dissolved oxygen and becomes a peroxide or its decomposition product, is treated with an adsorbent such as activated charcoal, activated clay, acid clay, silica gel, and fluorodil (Non-Patent Document 5, Non-Patent Document 5,). It is important to remove it in advance by a physical treatment such as patent document 11), molecular distillation (patent document 10), a treatment by a chromatographic method (non-patent document 5), etc., but in the present invention, the removal thereof is important. The removal method itself is not limited because it is not limited, but treatment with an adsorbent is preferable from the viewpoint of simplicity and high effectiveness. Further, the adsorbent treatment step may be inserted at any stage up to the antioxidant mixing step in the present invention, or may be carried out a plurality of times.

Further, for the detection of lipid peroxide and its decomposition products, any of the above-mentioned methods can be used in the present invention, and for example, _{thin layer chromatography using a silica gel 60PF 254} TLC plate (Merk, 0.25 mm thickness) is used. The imaging (TLC) method (Non-Patent Document 5) is preferable from the viewpoint of high accuracy and simplicity.

(Esterification reaction)
Esterification reactions of unsaturated fatty acids are well known, and typical examples thereof include an acid-catalyzed esterification reaction, an alkali-catalyzed esterification reaction, and an esterification reaction in the presence of an enzyme. Not limited to.

Further, the esterification reaction may be carried out in combination of two or more of these esterification reactions, if necessary. Preferably, the first esterification is carried out by an acid-catalyzed method or an enzymatic method, and then the esterification is carried out by an alkali-catalyzed method.

Since the polyunsaturated fatty acid of the present invention is intended for food use, an ethyl ester form is desirable.

(Esterification reaction under acid catalyst)
Well-known reaction conditions can be used for the esterification reaction of unsaturated fatty acids with lower alcohols under an acid catalyst. Typically, the reaction condition is stirring at 70 to 80 ° C. for about 5 hours.

(Esterification reaction under alkaline catalyst)
Well-known reaction conditions can be used for the esterification reaction of unsaturated fatty acids with lower alcohols under an alkali catalyst. Typically, the reaction condition is stirring at 70 to 80 ° C. for about 1 hour.

(Esterification reaction in the presence of enzyme)
There are no restrictions on the reaction time, temperature, etc. during the enzyme treatment. Those skilled in the art can utilize well-known conditions described in, for example, JP-A-2002-69475, JP-A-2013-5589, JP-A-2013-121366 and the like. The progress of the enzyme reaction can be controlled by AV measurement. The AV to be stopped can be arbitrarily set depending on the type of starting material, EPA purity, DHA purity, etc., depending on the quality of the target product, but generally, the reaction is stopped in the range of 30 to 130, preferably 70 to 100. do.

(Combination of esterification reactions)
The esterification reaction may be carried out by combining any two or more esterification reactions in any order, if necessary. When the inventors of the present application perform esterification of a raw material containing a highly unsaturated fatty acid having a high acid value (particularly, an acid value of 10 or more) by an alkali catalytic method, saponification of the highly unsaturated fatty acid occurs. It was found that the subsequent reaction did not proceed properly. Therefore, for raw materials having a high acid value, preferably, the first esterification is carried out by an acid catalyst method or an enzymatic method, and then the esterification is carried out by an alkali catalyst method.

When combined with an esterification reaction, the lower alcohol used in the first esterification reaction is preferably removed. Examples of the removal method include, but are not limited to, evaporation. The oil layer obtained after removal of the lower alcohol is washed with an aqueous solvent (for example, but not limited to water, hot water, and a buffer solution), if necessary. This wash is repeated as needed (eg, until the pH is neutral) and then subjected to the next esterification reaction.

(Measurement method of dissolved oxygen)
The measurement of dissolved oxygen in fats and oils is possible by a well-known method. There are no restrictions on the measuring instrument or the like used in the method for measuring dissolved oxygen in the ethyl ester mixture, but for example, according to Patent Document 8, a dissolved oxygen amount measuring device (fluorescent dissolved oxygen meter FOM-1000, stock). It can be measured using the company Automatic System Research).

(Method for reducing dissolved oxygen)
Techniques aimed at improving storage stability by reducing dissolved oxygen are known. That is, reduction of dissolved oxygen by adding hydroquinone to fats and oils (Non-Patent Document 4), flavor improvement method by substituting oxygen-containing dissolved gas in fats and oils with carbon dioxide (Patent Document 8), mayonnaise by substituting nitrogen gas, etc. A method for reducing dissolved oxygen in an oil-in-water emulsion and preventing deterioration of quality (Patent Document 9) is known and its effectiveness has been clarified.

The dissolved oxygen reduction method described in Patent Document 8 replaces the dissolved gas in the fat and oil composition with carbon dioxide until the dissolved amount of a gas other than carbon dioxide in the fat and oil composition reaches a specific range (for example, 8.5 mL). It is a method of replacement by bubbling at about / minute.

The method for reducing dissolved oxygen described in Patent Document 9 reduces the amount of dissolved oxygen in the composition to a certain concentration range when the target composition is filled in the resin container, and the oxygen permeability of the resin container is reduced. Is a method for reducing deterioration due to oxidation during storage by setting the value to a specific value or less and further replacing the inside of the container with an inert gas such as nitrogen when filling the resin container with the composition.

Dissolved oxygen in solutions containing polyunsaturated fatty acids (eg, polyunsaturated fatty acid ethyl esters) can be reduced, for example, by the nitrogen bubbling method. Although a substitution method using an inert gas such as carbon dioxide or argon can be achieved in addition to nitrogen, the method itself for reducing dissolved oxygen is not limited in the present invention (Patent Document 7).

When the dissolved oxygen in the polyunsaturated fatty acid ethyl ester exceeds 1 mg / L, the present inventors may cause the development of a fishy odor, an unpleasant offensive odor peculiar to fish oil during the subsequent powdering step or storage period. Therefore, in the present invention, the dissolved oxygen in the ω3 polyunsaturated fatty acid ethyl ester is limited to 1 mg / L or less. No lower limit has been set, but it goes without saying that the smaller the number, the higher the quality. Therefore, the dissolved oxygen content of the composition containing the polyunsaturated fatty acid or the polyunsaturated fatty acid ester of the present invention is preferably 1 mg / L or less, 0.8 mg / L or less, 0.6 mg / L or less, 0.4 mg. / L or less, 0.2 mg / L or less, 0.1 mg / L or less.

(Method of reducing peroxide value)
The peroxide value can be reduced by removing the lipid peroxide and its decomposition products. Many methods for removing lipid peroxides and their decomposition products are known. For example, a molecular distillation method (Patent Document 10 and Japanese Patent Application Laid-Open No. 2000-342291), an adsorbent treatment method (Patent Document 2, Patent Document 11, Patent Document 12, Patent Document 13) and the like are known, and the present invention relates to this method. Either method can be used. Experimentally, a method for removing lipid peroxide using a Florisil (100/200 mesh) column is known (Non-Patent Document 5).

The molecular distillation method can be carried out by, for example, a centrifugal molecular distillation method or a flow-down thin film type molecular distillation method. For example, in the case of flow-down thin-film molecular distillation, as described in JP-A-2000-342291, treatment is performed under the conditions of a vacuum degree of 0.005 mmHg, an evaporation surface temperature of 200 ° C., and a flow velocity of 30 g / L, and the fraction is used as a fraction. A free fatty acid fraction and a glyceride fraction can be obtained as a residual. In the case of the flow-down thin film type molecular distillation, the degree of vacuum, the evaporation surface temperature, and / or the feed amount in the molecular distillation operation can be appropriately changed by those skilled in the art depending on the type of the apparatus and the raw material oil.

It is also possible to remove lipid peroxides and their decomposition products by adsorbent treatment. Examples of the adsorbent used in the present invention include, but are not limited to, acidic clay, activated clay, activated carbon, silicic acid, and alumina. Preferably, the adsorbent is activated clay or silica gel. The activated clay is preferably activated clay that has been degassed and substituted with nitrogen, and the amount of the activated clay added is 1 to 20 wt% by weight of the product.

(Method of reducing acid value)
Since the ethyl ester mixture has a high content of highly unsaturated fatty acids, the ethyl group is likely to come off and become a free substance during the process of each step after the esterification reaction or during the storage period. It is necessary to remove the trace amount of free fatty acid produced because it not only deteriorates the quality of sensory evaluation due to its high oxidation rate but also increases the acid value. Similar to the above-mentioned peroxide reducing method, the acid value reducing method is effective, but is not limited to, physical means such as molecular distillation, adsorbent treatment and the like.

(Method for reducing anicidin value)
The anicidin value is said to be mainly derived from the aldehyde heat-denatured product refined during the fat processing process, and is an important index for sensory evaluation. Similar to the above-mentioned peroxide and acid value reduction methods, physical means such as molecular distillation, adsorbent treatment and the like are effective as the anicidin value reduction method, but the method is not limited thereto.

(Method for reducing peroxide value, acid value, and anicidin value)
The methods for reducing peroxide value, acid value, and anicidin value required in the present invention can be carried out simultaneously in, for example, a single method. For example, it is possible to carry out the degumming / deoxidizing treatment (Tetsuo Ono / Shizuyuki Ota, title "Edible oil / fat manufacturing technology", Business Center Co., Ltd. (1991), Tokyo) at the same time. ..

(Emulsification)
In the present invention, chicken egg products such as egg yolk and / or egg white can be used as an emulsifier. Egg yolk is not only a nutritionally excellent food material, but also has excellent emulsifying properties and contains about 50 wt% water. In the present invention, typically, the amount of dissolved oxygen is 1 mg / L or less, the fatty acid value is 3 or less, the acid value is 1 or less, the anicidin value is 5 or less, and the fatty acid is excessively treated with an adsorbent. The amount of egg yolk is 0.1 to 10 times the weight of the mixture containing the ethyl ester of the ω3 highly unsaturated fatty acid from which the oxide has been removed and the soybean phospholipid and vitamin E and ascorbic acid palmitate, that is, a dried product. Although it can be mixed in an amount of 0.05 to 5 times in terms of conversion, the ratio of the ω3 highly unsaturated fatty acid ethyl ester in the ω3 highly unsaturated fatty acid ethyl ester-containing composition which is the product is finally 20 wt% to 50 wt. In order to adjust to%, the purity of the ethyl ester of the target ω3 highly unsaturated fatty acid, the content of the ethyl ester of other coexisting ω3 highly unsaturated fatty acids, the amount of antioxidant used, egg yolk, egg white, etc. It is natural that it is necessary to adjust each time because it changes depending on the blending amount of the shaping agent and the like.

This mixture can be emulsified and mixed using an emulsifier, for example a high speed homogenizer. There is no limitation on the model of high-speed homogenizer, but Polytron (Central Scientific Trading Co., Ltd.) and Hiscotron (Microtech Nithion Co., Ltd.) can be used. The emulsification time, emulsification temperature, rotation speed, etc. differ depending on the model and scale, and also differ depending on the composition of the mixture, so there is no limitation in the present invention. Emulsification mixing for about 5 to 10 minutes is appropriate.

In the present invention, egg white is added to the emulsified mixture and a high-speed stirring process is performed. Since egg white contains albumin as a main component, it is useful not only for forming a complex with a fat-soluble component but also for forming a powder having excellent fluidity after undergoing a drying step. Egg white is usually composed of 10 to 13 wt% solid content and 87 to 90 wt% water, but in the present invention, assuming that the solid content of egg white is 12 wt%, ethyl ester of ω3 polyunsaturated fatty acid, It can be mixed in an amount of 1 to 20 times by weight, that is, 0.12 to 2.4 times in terms of dry product, with respect to the above emulsified mixture consisting of soybean phospholipid, vitamin E, ascorbic acid palmitate and egg yolk. However, in order to finally adjust the ratio of the ω3 polyunsaturated fatty acid ethyl ester in the ω3 polyunsaturated fatty acid ethyl ester-containing composition to 20 wt% to 50 wt%, the egg white blending amount is adjusted each time. There is a need to. This mixture can be stirred and mixed using a high speed stirrer, for example, a high speed homogenizer. There is no limitation on the model of high-speed homogenizer, but Polytron (Central Scientific Trading Co., Ltd.) and Hiscotron (Microtech Nithion Co., Ltd.) can be used. The stirring time, stirring temperature, rotation speed, etc. differ depending on the model and scale, and also differ depending on the composition of the mixture, so there is no limitation in the present invention. Mixing for about 5 to 10 minutes is appropriate.

In the above-mentioned high-speed stirring step of mixing egg whites, timely shaping is performed for the purpose of improving the fluidity of the final powdered product as a powder after the drying step, improving the properties such as blocking property, and further improving the oxidative stability. The agents can be added and mixed at the same time or by the powdering step. Examples of the excipient include dextrin, arabic gum, gelatin, agar, starch, pectin, carrageenan, casein, curdlan, alginic acid, soybean polysaccharide, pullulan, cellulose, xanthy gum, etc., but in the present invention, there are examples. The presence or absence of excipients is not a necessary requirement. The amount of the excipient added is the weight conversion ratio of the excipient in order to finally adjust the ratio of the ω3 polyunsaturated fatty acid ethyl ester in the composition containing the ω3 polyunsaturated fatty acid ethyl ester to 20 wt% to 50 wt%. It needs to be adjusted each time.

In order to prevent the mixing of new dissolved oxygen and the mixing of air during the mixing process, the high-speed stirring step of mixing egg yolk and egg white is, of course, under the environment of an inert gas such as nitrogen gas, argon or carbon dioxide. It is desirable to operate with.

The mixed emulsion of ω3 polyunsaturated fatty acid ethyl ester, antioxidant, egg yolk, egg white and excipient obtained in the above steps is a powdered body with a water content of 6 wt% or less after the drying step. The composition contains an unsaturated fatty acid ethyl ester. In the present invention, the lower limit of the water content in the product is not defined, but it is usually expected to be 2 wt% or more. As a drying method, a spray drying method or a freeze drying method can be used, but in the present invention, the spray drying method is preferable. In the present invention, the spray drying method is positioned as a microencapsulation technique (Hideo Takenaka, entitled "Recent Advances in Spray Drying Method as a Microencapsulation Method", Gifu Pharmaceutical University Bulletin 32, 1-14 ( 1983-06-03)). That is, the core material is mainly composed of ω3 polyunsaturated fatty acid ethyl ester and antioxidant, and the wall material is mainly composed of emulsifiers and excipients such as egg white. The fat-soluble substances in the egg yolk component are mainly distributed on the core substance side, and the water-soluble substances are distributed on the wall substance side, but they are also involved in the maintenance of the capsule structure due to their properties as emulsifiers.

(Powdered)
Various well-known methods such as a spray drying method can be used for powdering the composition of the present invention. In the production of the powder composition by the spray drying method, the inlet temperature, outlet temperature, liquid feed amount, etc. of the spray dryer vary depending on the physical characteristics of the undiluted solution, the content of the mixture, restrictions on equipment operation, etc., and therefore, in the present invention. There are no restrictions.

The ω3 polyunsaturated fatty acid ethyl ester-containing composition prepared in the above steps may be stored at room temperature as it is, or may be stored in a packaging material having a high gas barrier property in the presence of an oxygen scavenger, for example. It may be stored refrigerated or frozen, but for example, when long-term storage of 6 months or more is required, it is better to store frozen in a packaging material with high gas barrier properties in the presence of an oxygen scavenger. Naturally.

The ω3 highly unsaturated fatty acid ethyl ester-containing composition can be added to all foods that are physically allowed to be mixed, but in general, "food industry" (Masao Fujimaki, Hiroshi Miura, Kenichi Otsuka, Shunji Kawabata)・ Breads, noodles, confectionery, oil and fat foods such as plants, soy protein foods, miso, dairy products, meat products, egg products, fish meat, which are described and defined in Kimura Susumu ed. It can be added to paste products and instant foods. The present invention is based on the food classification defined in "Recent Advances in Spray Drying as a Microencapsulation Method" above.

(Application to food)
It is also a feature of the present invention that a specific texture can be obtained when the protein in egg yolk and egg white contained in the composition containing ω3 polyunsaturated fatty acid ethyl ester is accompanied by heat denaturation when used in foods. be. Needless to say, it is possible to use a masking flavor each time it is used for food.

The composition of the present invention contains 1 wt% or more, 2 wt% or more, 3 wt% or more, 4 wt% or more, 5 wt% or more, 6 wt% or more, 7 wt% or more, 8 wt% or more, 9 wt% or more, 10 wt% or more, in food. It contains 15 wt% or more, 20 wt% or more, and 30 wt% or more. Further, the composition of the present invention is 90 wt% or less, 80 wt% or less, 70 wt% or less, 65 wt% or less, 60 wt% or less, 55 wt% or less, 55 wt% or less, 50 wt% or less, 40 wt% or less, 30 wt% or less in food. included. For example, the composition of the present invention is 1 wt% to 70 wt%, 2 wt% to 65 wt%, 3 wt% to 60 wt%, 4 wt% to 55 wt%, 5 wt% to 50 wt%, 7 wt% to 40 wt%, or It contains 10 wt% to 30 wt%.

The food of the present invention is not particularly limited, but for example, breads, noodles, confectionery, oil and fat foods such as plants, soy protein foods, miso, dairy products, meat products, egg products, fish paste products, and / Alternatively, it includes, but is not limited to, instant foods.

(Polyunsaturated fatty acid or polyunsaturated fatty acid ester of the present invention)
The peroxide value of the composition containing the highly unsaturated fatty acid or the highly unsaturated fatty acid ester of the present invention is 3 or less, 2 or less, 1 or less, 0.5 or less, 0.2 or less, 0.1 or less. Not limited to these.

The acid value of the composition containing the polyunsaturated fatty acid or the polyunsaturated fatty acid ester of the present invention is 1 or less, 0.8 or less, 0.6 or less, 0.4 or less, 0.2 or less, 0.1 or less. Yes, but not limited to these.

The composition containing the polyunsaturated fatty acid or the polyunsaturated fatty acid ester of the present invention has anicidin value of 5 or less, 4 or less, 3 or less, 2 or less, 1 or less, 0.5 or less, 0.2 or less, 0.1. The following, but not limited to these.

The composition containing the highly unsaturated fatty acid or the highly unsaturated fatty acid ester of the present invention typically has a dissolved oxygen content of 1 mg / L or less, a peroxide value of 3 or less, an acid value of 1 or less, and an anisidin value of 5. It is as follows. Preferably, the composition of the invention comprises an antioxidant and / or an emulsifier. Preferably, the composition of the present invention is provided as a powder product.

Hereinafter, the present invention will be described based on examples, but the following examples are provided for purposes of illustration only. Therefore, the scope of the present invention is not limited to the detailed description of the above invention or the following examples, but is limited only by the claims.

(Example 1: Removal of peroxide and removal of dissolved oxygen)
To 900 g of bonito raw material oil (produced in Makurazaki, Kagoshima Prefecture) having a DHA purity of 25.5 wt%, 600 mL of 99% ethanol and 62.5 g of concentrated sulfuric acid were added, and the mixture was stirred at 70 to 80 ° C. for 5 hours. After stirring, ethanol was removed under a vacuum degree of 0.1 MPa and an evaporation surface temperature of 100 ° C. Then, the oil layer was washed with about 150 mL of hot water, and the process was repeated until the pH of the washing hot water became 2 or more. Then, impurities were removed by pressure filtration. After pressure filtration, alkaline alcohol (4.5 g of sodium hydroxide dissolved in 180 mL of 60% ethanol in advance) was added, and the mixture was stirred at 70 to 80 ° C. for 1 hour. After stirring, the oil layer was washed with about 150 mL of hot water and repeated until the pH of the washing water became 7 or less. Then, the solvent was removed under a vacuum degree of 0.1 MPa and an evaporation surface temperature of 100 ° C. As a result, 860 g of ethyl ester was obtained. Subsequently, 800 g of the crude fatty acid ethyl ester was treated by a centrifugal molecular distillation method at a vacuum degree of 1.5 Pa and a evaporation surface temperature of 180 ° C. to obtain 760 g of the fatty acid ethyl ester as a distillate, and one of the fatty acid peroxides. The impurity fraction containing the ester and unreacted fatty acid was separated as a distillation residue on the molecular distillation residue side. For 760 g of the fatty acid ethyl ester, 110 g of an ethyl ester mixture having a DHA purity of 90 wt% was obtained by using a method using vacuum precision distillation, high performance liquid chromatography (Patent Document 4) and a silver complex method (Japanese Patent Application No. 2015-111793). ..

100 g of the ethyl ester mixture has a peroxide value (POV) of 4.4, AV0.1 and anicidin value of 2.6, and is a developing solvent for neutral lipids (n-hexane / diethyl) by silica gel thin layer chromatography (TLC). When qualitatively confirmed using ether / acetic acid = 85/15/1), the presence of peroxide was observed near the origin. Further, when tested by a thin layer chromatography (TLC) method (Non-Patent Document 5) using a silica gel 60PF ₂₅₄ TLC plate (Merk, 0.25 mm thickness), spots corresponding to peroxides or their decomposition products were found. was detected.

95 g of the ethyl ester mixture was eluted with n-hexane on a Florisil (100/200 mesh) column, the peroxide was adsorbed and removed on Frosylyl, and hexane was removed from the eluate under reduced pressure by nitrogen gas streaming. Subsequently, the same treatment was performed on a silica gel (Merk, silica gel 60) column to obtain 80 g of a product.

Subsequently, 80 g of the fatty acid ethyl ester was deoxidized by a nitrogen bubbling method (Patent Document 9, Japanese Patent Application Laid-Open No. 2005-110674), and this was degassed with 0.4 L of n-hexane and 4 g of degassed active white clay. , 2 g of degassed silica gel is added, and the mixture is stirred in a nitrogen gas environment at room temperature for 30 minutes to filter out the hexane layer containing the fatty acid ethyl ester fraction, and then n-hexane is removed by a vacuum evaporator. Then, the residual trace amount of dissolved oxygen and n-hexane were removed again by the nitrogen bubbling method.

The dissolved oxygen concentration of 70 g of the obtained product was 0.3 mg / L when measured with a dissolved oxygen amount measuring device (fluorescent dissolved oxygen meter FDM-1000, manufactured by Automatic System Research Co., Ltd.), and the peroxide value (POV). ) 0.1, AV0.1, anicidin value 1.0, and used in a developing solvent for neutral lipids (n-hexane / diethyl ether / acetic acid = 85/15/1) by silica gel thin layer chromatography (TLC). As a result of qualitative confirmation, the presence of peroxide was not observed near the origin. Furthermore, when tested by a thin layer chromatography (TLC) method using a silica gel 60PF ₂₅₄ TLC plate (Merk, 0.25 mm thick), no spots corresponding to peroxides and their decomposition products were confirmed. Further, when tested by a thin layer chromatography (TLC) method (Non-Patent Document 5) using a silica gel 60PF ₂₅₄ TLC plate (Merk, 0.25 mm thickness), the spot corresponding to the peroxide or its decomposition product is found. Not detected.

(Example 2: Antioxidant mixing, emulsification and powdering)
To 100 g of a fatty acid ethyl ester mixture having a DHA purity of 90 wt% prepared by the method of Example 1, 0.3 g of mixed tocopherol (trade name: RIKEN E Oil, RIKEN Vitamin Co., Ltd.), soybean lecithin (trade name: SLP-paste, Tsuji Oil Co., Ltd.) 3.0 g and ascorbic acid palmitate (trade name: L-ascorbic acid palmitate, DSM Japan Co., Ltd.) 0.05 g are mixed and stirred under nitrogen gas bubbling for 3 hours to dissolve. , Antioxidant-containing fatty acid ethyl ester mixture was obtained. The dissolved oxygen concentration of this mixture is 0.3 mg / L, the peroxide value (POV) is 0.1, AV0.1, the anicidin value is 1.2, and the mixture is neutral by silica gel thin layer chromatography (TLC). When qualitatively confirmed with a developing solvent for lipids (n-hexane / diethyl ether / acetic acid = 85/15/1), the presence of peroxide was not observed near the origin.

200 g of egg yolk (Taiyo Kagaku Co., Ltd.) is mixed with 100 g of the above antioxidant-containing fatty acid ethyl ester mixture, and the headspace portion of the container is replaced with nitrogen at 10000 rpm under ice-cooling Polytron (Central Kagaku Trading Co., Ltd.). It was emulsified for 5 minutes. Subsequently, 400 g of egg white (Taiyo Kagaku Co., Ltd.) was added and homogenized with a polytron under ice-cooling at 10000 rpm for 5 minutes to obtain an ω3 polyunsaturated fatty acid ethyl ester-containing composition before drying. The calculated solid content of this is assumed to be 35.7% (250 g).

200 g of the above mixture (including 71.4 g of solid content) was spray-dried using a spray dryer (GB210 type, Yamato Kagaku Co., Ltd.) to obtain an ω3 polyunsaturated fatty acid ethyl ester-containing composition. The spray drying conditions were an inlet temperature of 180 ° C., an outlet temperature of 100 ° C., a liquid feed rate of 3 ml / min, and a spray pressure of 1.2 kg / cm ² .

The obtained composition containing ω3 polyunsaturated fatty acid ethyl ester was 43 g (solid content recovery rate 60.2%), and the water content was 3.5% when measured with an infrared moisture meter.

In addition, when the odor of the volatile component was sensory-tested by a panel of 5 people, all of them did not detect the fishy odor peculiar to fish oil and evaluated it as good. Furthermore, even when this composition was ingested, all of them did not detect the fishy odor peculiar to fish oil and evaluated it as good. From this, it was proved that a composition containing ω3 polyunsaturated fatty acid ethyl ester having very good quality could be obtained.

The obtained ω3 polyunsaturated fatty acid ethyl ester-containing composition was placed in an aluminum packaging material having a high gas barrier property together with an oxygen scavenger and stored at −20 ° C. until use.

72 g of total lipid was extracted from 100 g of the ω3 polyunsaturated fatty acid ethyl ester-containing composition obtained by repeating the above steps by the chloroform-methanol method. The DHA ethyl ester contained in this product was 59.5 wt%, had a POV of 1.8, and had an anisidin value of 0.9. AV, dissolved oxygen, peroxides, etc. were not analyzed because they are affected by components derived from antioxidants such as soybean lecithin.

From the above results, the DHA ethyl ester content in the ω3 polyunsaturated fatty acid ethyl ester-containing composition was 42.8 wt%.

(Example 3: Excipient)
To 200 g of the ω3 polyunsaturated fatty acid ethyl ester-containing composition obtained in Example 2 before drying, 30 g of dextrin (trade name: Pineflow, Matsutani Chemical Industry Co., Ltd.) and 100 ml of water were added as excipients. Then, the homogenization treatment was carried out with a polytron under ice-cooling at 3000 rpm for 5 minutes. The calculated solid content of this product is assumed to be 30.7% (101 g).

200 g of the above mixture (including 61.4 g of solid content) was spray-dried under the same conditions as in Example 2. The obtained ω3 polyunsaturated fatty acid ethyl ester-containing composition was 49 g (solid content recovery rate 79.8%), and the water content was 3.5% when measured with an infrared moisture meter. From this, it was confirmed that the use of the excipient improved the fluidity of the powder during spray drying and improved the recovery rate.

In addition, when the odor of the volatile component was sensory-tested by a panel of 5 people, all of them did not detect the fishy odor peculiar to fish oil and evaluated it as good. Furthermore, even when this food was eaten, all of them did not detect the fishy odor peculiar to fish oil and evaluated it as good. From this, it was proved that a composition containing ω3 polyunsaturated fatty acid ethyl ester having very good quality could be obtained. The obtained composition containing the ω3 polyunsaturated fatty acid ethyl ester was placed in an aluminum packaging material having a high gas barrier property together with an oxygen scavenger and stored at −20 ° C. until use.

From 100 g of the ω3 polyunsaturated fatty acid ethyl ester-containing composition obtained by repeating the above steps, 50 g of total lipid was extracted by the chloroform-methanol method. The DHA ethyl ester contained in this product was 61.0 wt%, had a POV of 1.5, and had an anisidin value of 0.6. AV, dissolved oxygen, peroxides, etc. were not analyzed because they are affected by components derived from antioxidants such as soybean lecithin.

From the above results, the DHA ethyl ester content in the ω3 polyunsaturated fatty acid ethyl ester-containing composition was 30.5 wt%.

(Example 4: Udon)
As noodles, a test for adding an ω3 polyunsaturated fatty acid ethyl ester-containing composition to udon was conducted. Udon noodles are cited in Reference 8 (Shigehisa Shibata, 4-1 Raw noodles, dried noodles, food industry, Masao Fujimaki et al., Pp59-74 (1985), Koseisha Koseikaku (Tokyo)) and "New Edition Tegaru Noodles". Prototypes were made according to "Processed foods" (edited by Yu Minoshita and Akio Tsukui, pp120-121, Kenzosha (1991), Tokyo).

The raw materials were 380 g of wheat flour, 20 g of salt, 180 mL of water, and flour (appropriate amount). That is, 20 g of salt dissolved in 180 mL of water and 100 g of the ω3 polyunsaturated fatty acid ethyl ester-containing composition (DHA ethyl ester content 42.8 wt%) prepared in Example 2 are added to 380 g of medium-strength flour and mixed. The udon boiled noodles were prepared through rolling, cutting, boiling, and washing with water. In this example, the dry matter weight of the udon noodles is 500 g, and the DHA ethyl ester content is designed to be 8.6 wt% in terms of dry matter.

The raw udon noodles were sensory-tested by a panel of 5 people according to the soup of commercially available udon noodles. As a result, when the odor of the volatile component was sensory-tested, all of them did not detect the fishy odor peculiar to fish oil and evaluated it as good. Furthermore, even when this food was eaten, all of them did not detect the fishy odor peculiar to fish oil and evaluated it as good. From this, it was proved that a composition containing ω3 polyunsaturated fatty acid ethyl ester having very good quality could be obtained.

(Example 5: Instant miso soup)
A test for adding an ω3 polyunsaturated fatty acid ethyl ester-containing composition to miso and ready-to-eat foods was carried out. Instant miso soup (trade name "Asage", Nagatanien Co., Ltd.) 1 serving of paste-like miso 16.3 g (assuming a solid content of 40%), 160 mL of boiling water, ω3 polyunsaturated fatty acid ethyl ester prepared in Example 2. 1 g of the contained composition (DHA ethyl ester content 42.8 wt%) was added and mixed. Similarly, a test group in which 2 g, 3 g, and 4 g of the ω3 polyunsaturated fatty acid ethyl ester-containing composition prepared in Example 2 were added and mixed was also prepared, and both were subjected to a sensory test.

In this example, the dry matter weight of the above-mentioned paste-like miso is 7.52 g in the group in which 1 g of the ω3 polyunsaturated fatty acid ethyl ester-containing composition is added and mixed, and 8.52 g and 3 g in the group in which 2 g is added and mixed. In addition, it was 9.52 g in the mixed group and 10.52 g in the group in which 4 g was added, and the amount of the ω3 polyunsaturated fatty acid ethyl ester-containing composition added was 13.3 wt% and 23.5 wt%, respectively. It is 31.5 wt% and 38.0 wt%. Therefore, the DHA ethyl ester contained in a cup of this instant miso soup is 5.7 wt%, 10.0 wt%, 13.5 wt%, and 16.3 wt, respectively.

When the odor of the volatile components rising from the resulting miso juice was sensory-tested, all of the test plots to which the ω3 polyunsaturated fatty acid ethyl ester-containing composition was added, 1 g, 2 g, and 3 g, were found. The fish oil-specific fishy odor was not detected and was evaluated as good. Furthermore, even when this food was eaten, all the test plots did not detect the fishy odor peculiar to fish oil and evaluated it as good. From this, it was proved that a composition containing ω3 polyunsaturated fatty acid ethyl ester having very good quality could be obtained.

Furthermore, in the test group to which 4 g of the ω3 polyunsaturated fatty acid ethyl ester-containing composition was added, all of them sensed a fishy odor, but did not detect a fishy and unpleasant offensive odor peculiar to fish oil, and evaluated it as good. Furthermore, all of them sensed the fishy odor when they ate this food, but they did not detect the fishy odor peculiar to fish oil and evaluated it as good. From this, it was proved that a composition containing ω3 polyunsaturated fatty acid ethyl ester having very good quality for miso and instant miso soup could be obtained.

In addition, since miso soup is originally compatible with seafood-based flavors such as bonito and irico-dashi, all of the test plots to which the ω3 polyunsaturated fatty acid ethyl ester-containing composition was added were blank (ω3 polyunsaturated fatty acid). It is a remarkable effect of the present invention that it is evaluated to be richer and tastier than the miso soup containing no saturated fatty acid ethyl ester-containing composition.

The present invention makes it possible to prevent and / or delay the progress of oxidation of polyunsaturated fatty acids or polyunsaturated fatty acid esters during the process of commercialization and the shelf life of the product. INDUSTRIAL APPLICABILITY The present invention provides a technique for keeping the progress of oxidation in the process of commercialization and the progress of oxidation during the storage period of the product within a level at which the appearance of offensive odor is not noticed by sensory evaluation.

Claims (8)

A composition containing 10 wt% or more of ethyl ester of polyunsaturated fatty acid.
Here, the polyunsaturated fatty acids are docosahexaenoic acid (C22: 6, DHA), eicosapentaenoic acid (C20: 5, EPA), arachidonic acid (C20: 4, AA), docosapentaenoic acid (C22: 5,). DPA), stearidonic acid (C18: 4, SDA), α-linolenic acid (C18: 3, ALA), and linoleic acid (C18: 2) selected from the group.
The composition has a dissolved oxygen content of 1 mg / L or less, a peroxide value of 3 or less, an acid value of 1 or less, and an anisidin value of 5 or less. The composition according to claim 1, further comprising an antioxidant. The composition according to claim 1 or 2, further comprising an emulsifier. The composition according to claim 2, wherein the antioxidant is selected from the group consisting of soybean phospholipids, vitamin E, and ascorbic acid palmitate. The composition according to claim 3, wherein the emulsifier is selected from the group consisting of egg yolk and egg white. The composition according to claim 1, which is a spray-dried product having a water content of 5 wt% or less. The composition according to claim 1, which contains 40 wt% to 99 wt% of an ester of a polyunsaturated fatty acid selected from the group consisting of α-linolenic acid, stearidonic acid, eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid. .. The composition according to claim 1, wherein the total content of the ester of the polyunsaturated fatty acid in the composition is 20 wt% to 60 wt%.