JP2013094145A - Pet food - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pet food containing unsaturated fatty acid-containing oil and fat and having high preservation stability and palatability.SOLUTION: The pet food contains the following components (A)-(E): (A) oil and fat containing, as constituent fatty acid, unsaturated fatty acid containing two or more double bonds, (B) a mineral component selected from iron, an iron compound, copper, and a copper compound, (C) citric acid and/or its salt, the total amount being not less than 10 times of the component (B) at a molar ratio, (D) lecithin, and (E) a rosemary extract.

Description

  The present invention relates to a pet food containing an unsaturated fatty acid-containing fat.

  Due to the pet boom, the number of pets is increasing, and with it, diseases similar to human adult diseases such as pet obesity, diabetes and liver disease are increasing due to aging of pets, lack of exercise, overnutrition and the like. In addition, dogs and cats who become obese due to hormonal imbalance after contraceptive surgery are increasing. Many pet foods for preventing such obesity and weight gain have been developed. For example, pet foods containing fats and oils with a high unsaturated fatty acid content have been proposed.

  Such pet foods contain a large amount of unsaturated fatty acids, so that they are easily oxidized depending on the storage environment, and may affect odor, palatability and the like. In view of this, the present applicant, in a pet food with a high mineral content, includes a technology for blending vitamin C derivatives (Patent Document 1), a naturally occurring antioxidant, and the content of iron ions and copper ions in the pet food. It has been proposed to improve long-term storage stability by controlling technology (Patent Document 2).

  Moreover, as an antioxidant system for food applications, a combination of a glyceride having a medium chain fatty acid as a constituent fatty acid and an antioxidant (Patent Document 3), a bayberry extract, a water-soluble antioxidant and a lipophilic antioxidant A combination (Patent Document 4), a combination of a mushroom mycelium culture filtrate and the like and an antioxidant (Patent Document 5) has been proposed.

JP 2005-204659 A JP 2007-110916 A JP 2004-115758 A JP 2007-185138 A Japanese Patent Laid-Open No. 7-59548

  In recent years, as the health-consciousness of pets has increased, fats and oils composed of fatty acids having many unsaturated bonds in the molecule, such as ω3 fatty acids and ω6 fatty acids that are expected to have various physiological effects, have been developed. There is a need for pet foods that contain a large amount. However, these fatty acids are very easy to oxidize and it is difficult to express a physiological effect over a long period of time. Accordingly, there is a demand for achieving long-term storage stability in pet foods containing oils and fats containing such highly unsaturated fatty acids as constituent fatty acids.

Therefore, the present inventors have examined the long-term storage stability of pet foods containing fats and oils containing unsaturated fatty acids having two or more double bonds as constituent fatty acids. It has been found that the addition of a simple metal salt, particularly copper or iron, promotes the oxidation of the fats and oils and does not provide a pet food that is stable against oxidation containing both. Therefore, various studies were conducted to improve its oxidative stability. As a result, catechin, vitamin E, lecithin, vitamin C, carotene, etc., which are considered to have an anti-oxidant effect, contained unsaturated fatty acid-containing fats and metals. It was found that the oxidation of the salt-containing pet food could not be sufficiently prevented, but the oxidation could be remarkably prevented by adding citric acid or its salt in a predetermined amount or more.
As a result of studying to further improve the stabilizing action against oxidation of pet food by the citric acid or its salt combination, the present inventor surprisingly found that lecithin and rose which hardly have an antioxidant action when added alone. It has been found that the stability of pet food containing unsaturated fatty acid-containing fats and metal salts can be remarkably improved if the Marie extract is blended with a certain amount or more of citric acid or a salt thereof, and the present invention has been completed.

That is, this invention provides the pet food containing the following component (A)-(E).
(A) an oil or fat containing an unsaturated fatty acid having two or more double bonds as a constituent fatty acid,
(B) Mineral component selected from iron, iron compound, copper and copper compound,
(C) citric acid and / or salt thereof, the total amount is 10 times or more of component (B) in molar ratio,
(D) Lecithin (E) Rosemary extract

  In addition, the present invention is a composition containing (A) an oil or fat containing an unsaturated fatty acid having two or more double bonds as a constituent fatty acid, and (B) a mineral component selected from iron, an iron compound, copper and a copper compound. (C) citric acid and / or salt thereof, the total amount is 10 times or more of component (B) in a molar ratio, (D) lecithin, (E) rosemary extract, The present invention provides a method for preventing oxidation of the composition.

  The pet food of the present invention is remarkably excellent in long-term storage stability. Therefore, when blended with fats and oils containing a large amount of highly unsaturated fatty acids such as ω3 and 6 as constituent fatty acids, the expected physiological function can be expressed over a long period of time. Moreover, the change of the smell accompanying the oxidation of a fatty acid, the fall of palatability, etc. can be suppressed effectively.

It is a figure which shows the progress change of the electrical conductivity of a sample. It is a figure which shows the result of having evaluated the antioxidant power of the various antioxidant with respect to the composition containing fats and oils and a mineral component by the rancimat test method.

The pet food of the present invention contains (A) an oil and fat containing an unsaturated fatty acid having two or more double bonds (hereinafter also simply referred to as a highly unsaturated fatty acid) as a constituent fatty acid. The content of polyunsaturated fatty acids in the constituent fatty acids of the fats and oils is 20 to 90% by mass (hereinafter simply referred to as%), more preferably 23 to 80%, especially 25 to 25% from the viewpoint of pet skin and hair health. 70% is preferable. In addition, the content of fats and oils containing highly unsaturated fatty acids as constituent fatty acids in the pet food is preferably 2 to 45%, more preferably 2.5 to 40%, and still more preferably 3 to 35%. Here, as a highly unsaturated fatty acid, a C18-24 highly unsaturated fatty acid is mentioned as a suitable thing. An example of an unsaturated fatty acid having two double bonds is linoleic acid. Moreover, it is preferable from the viewpoint which can expect many physiological effects to contain many unsaturated fatty acids which have three or more double bonds. As the unsaturated fatty acid, α-linolenic acid, γ-linolenic acid, arachidonic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) are preferable, and the content of the fatty acid in the constituent fatty acid of the component (A) fats and oils Is preferably 3.0% or more, more preferably 3.5% or more, and still more preferably 4.0% or more.
In addition, as a fatty acid which comprises the fats and oils of a component (A), you may contain the unsaturated fatty acid and saturated fatty acid which have one double bond other than a highly unsaturated fatty acid. Here, examples of the unsaturated fatty acid having one double bond include unsaturated fatty acids having 16 to 24 carbon atoms, and oleic acid, palmitooleic acid and the like are preferable. Moreover, as a saturated fatty acid, a C12-C18 saturated fatty acid is mentioned, A palmitic acid, a stearic acid, etc. are suitable.

In addition, the content of unsaturated fatty acids having two or more double bonds in the constituent fatty acids of all fats and oils contained in pet food is preferably 5% to 80%, more preferably 10 to 75%, and even more preferably 15 to 70%. Preferably, 20 to 65% is more preferable.
In this invention, you may contain fats and oils which do not contain fats and oils other than a component (A), ie, a highly unsaturated fatty acid, as a constituent fatty acid. The content of total fats and oils in the pet food of the present invention is preferably 6 to 50%, more preferably 6 to 45%, still more preferably 6 to 40%, from the viewpoint of palatability and removal of unpleasant odor of the pet food. -35% is particularly preferred.

  As the oils and fats used in the pet food of the present invention, safflower oil, olive oil, cottonseed oil, corn oil, rapeseed oil, soybean oil, palm oil, sunflower oil, linseed oil containing the above highly unsaturated fatty acids as constituent fatty acids, Sesame oil, lard, beef tallow, fish oil, milk fat, coconut oil, coconut oil, rice bran oil, shiso oil, sesame oil, evening primrose oil, hemp seed oil and the like. Among these, linseed oil, fish oil, shiso oil, sesame oil, evening primrose oil, and hemp seed oil containing many unsaturated fatty acids having three or more double bonds as constituent fatty acids are preferable. However, it is not restricted to what was mix | blended as fats and oils, and when this is contained in other plant raw materials or animal raw materials, this is also included. Moreover, diglyceride may be contained in the fats and oils.

  The pet food of the present invention also contains a mineral component selected from iron, an iron compound, copper and a copper compound as the component (B). Examples of the iron compound include iron sulfate, ferric chloride, ferrous fumarate, ferrous carbonate, and iron oxide. The content of the iron compound in the pet food is within an acceptable range in pet food blending, 0.00001 to 1% in terms of iron, 0.00005 to 0.3%, particularly 0.0001 to 0.1%. Is preferred.

  Examples of the copper compound include copper sulfate, copper chloride, copper oxide, copper carbonate, copper sulfide, copper chlorophyll and the like. The content of the copper compound in the pet food is within an acceptable range in the pet food formulation, 0.00001 to 0.1% in terms of copper, 0.00005 to 0.03%, particularly 0.0001 to 0.00. 01% is preferred.

  Of these mineral components, iron or an iron compound and copper or a copper compound are preferably used in combination. In the present invention, the total content of these mineral components is preferably 0.0005 to 1%, more preferably 0.0005 to 0.5% in terms of mineral (in terms of iron and copper), and 0.001 to 0.001. 0.1% is more preferable.

  The pet food of the present invention may contain manganese, cobalt, calcium, phosphorus, sodium, potassium and the like as a mineral component in addition to iron and copper. These mineral components are blended as, for example, manganese oxide, cobalt carbonate, calcium carbonate, calcium phosphate, sodium chloride, potassium chloride and the like.

  The pet food of the present invention further contains citric acid and / or a salt thereof as component (C), and the total amount thereof is 10 times or more in molar ratio with respect to component (B). Here, examples of the citrate include alkali metal salts and alkaline earth metal salts, and alkali metal salts are particularly preferable. The alkali metal salt means a normal salt of citric acid (trialkali metal salt), a monohydrogen dialkali metal salt, and a dihydrogen alkali metal salt. Examples of the alkali metal salt of citric acid include sodium salt and potassium salt, and sodium salt is particularly preferable. In the present specification, unless otherwise specified, sodium citrate represents trisodium citrate (dihydrate).

  When the total amount of citric acid and its salt is 10 times or more in terms of molar ratio to the metal of component (B), the antioxidant effect due to the combined use of citric acid and / or its salt and lecithin is synergistically improved. To do. The total amount of the component (C) is preferably 11 times or more, more preferably 12 times or more in terms of molar ratio to the component (B). Further, the total amount of citric acid or a salt thereof is preferably 60 times or less in terms of molar ratio with respect to component (B) from the viewpoint of palatability.

In addition, the component (C) is preferably contained in the pet food in an amount of 0.5% or more in terms of citric acid. Here, “in terms of citric acid” means that the component (C) contains citric acid and an alkali metal or alkaline earth metal salt of citric acid (hereinafter also referred to as citric acid), or the component (C ) Is only an alkali metal or alkaline earth metal salt of citric acid, it means that the alkali metal content and alkaline earth metal content are replaced with hydrogen, and the mass is converted with the molecular weight of citric acid.
The pet food of the present invention preferably contains citric acids in an amount of 0.7% or more, further 0.75% or more, and further 1.0% or more in terms of citric acid from the viewpoint of storage stability and palatability. . The upper limit of the citric acid content is preferably 5.0%, more preferably 4.0% in consideration of palatability and odor during storage.

  The pet food of the present invention further contains lecithin as component (D). Lecithin means phosphatidylcholine in a narrow sense, but broadly means glycerophospholipid. The phosphatidylethanolamine preferably used in the present invention is a kind of glycerophospholipid and is included in lecithin in a broad sense. When lecithin is used for commercial or industrial purposes, it means glycerophospholipid in a broad sense and is often a mixture containing glycerophospholipid as a main component.

  Examples of (D) lecithin used in the present invention include soybean lecithin, powdered soybean lecithin, egg yolk lecithin, hydrogenated soybean lecithin, hydrogenated egg yolk lecithin, rapeseed lecithin, corn lecithin, bovine brain lecithin, and bovine liver lecithin. In addition, as a component of soybean lecithin generally used in food and feed, phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidic acid (PA) are present in descending order of content. These alone are treated as lecithin in the present invention. Moreover, PC-DHA etc. which DHA couple | bonded as a constituent fatty acid of PC are also mentioned as a lecithin. Of these, PE was found to have high antioxidant activity. Therefore, the mixture preferably has a high PE content, and soy lecithin, powdered soy lecithin, hydrogenated soy lecithin, and egg yolk lecithin are more preferable from the viewpoint of flavor, odor, and cost.

Component (D) is preferably contained in an amount of 0.3% or more, more preferably 0.5% or more based on the fat of component (A) from the viewpoint of the antioxidant effect. From the viewpoint of higher antioxidant effect and flavor, it is preferably 0.6% or more and 20.0% or less, more preferably 1.0% or more and 15.0% or less.
In the present invention, the amount of lecithin (D) refers to an amount in terms of phospholipid, which is acetone-insoluble, and this amount in terms of phospholipid is edited by Japan Oils and Fats Science Society, “Standard Oil Analysis Test Method 5.3.3.1”. It can be measured by the method described in “-86 Phospholipid Phosphorus Composition”. For example, soy lecithin generally used in foods and the like includes acetone-soluble components such as triglyceride, and is intended to exclude such components. The amount of lecithin that is insoluble in acetone is often about 60% in a lecithin source (for example, an agent marketed as soybean lecithin). Moreover, a component (D) is 0.06-6.0% in the pet food whole quantity of this invention from a viewpoint of an antioxidant effect and flavor, Furthermore, 0.1-3%, Furthermore, 0.2-2.0% It is preferable to contain. Moreover, it is preferable from the viewpoint of a high antioxidant effect that it is 0.5% or more and 75% or less with respect to the highly unsaturated fatty acid which is a structural component of the fat of component (A), and also 0.5% or more and 50% or less. .

  The present invention further comprises (E) a rosemary extract. The rosemary extract is a water and / or organic solvent extract of leaves of rosemary, which is a plant of the family Lamiaceae, and has an aroma unique to rosemary, which is generally an herb. More specifically, it can be obtained by drying, pulverizing, and extracting rosemary leaves with water, hot water, hexane, ethanol, acetone, ethyl acetate, or a mixed solvent thereof. In the present invention, in addition to the above-mentioned extract by water and / or organic solvent, oleoresin preparations formulated with the same or preparations such as rosmanol, carsonol, and isorosmanol, which are constituents, may be used. A product obtained by deodorizing these extracts by a depressurization method, a heating depressurization method, a supercritical extraction method, a column adsorption method or the like (hereinafter referred to as a deodorized product) is particularly preferred in terms of flavor. Here, as a commercially available product of rosemary extract, Harbor Rocks Type O, Type HT-O, Type 25, Duolite NMH, NM-1 (above, manufactured by Calsec Co., Ltd.), Leomile E, Leomile IO ( As mentioned above, Lion Corp.) RM Keeper (above, manufactured by Mitsubishi Chemical Foods) and the like can be mentioned.

  (E) Rosemary extract is contained in an amount of 0.04% or more as an extract (no solvent) with respect to the fat of component (A) from the viewpoint of the antioxidant effect. From a higher antioxidant effect, flavor, and economical viewpoint, it is preferably 0.04% or more and 0.4% or less, more preferably 0.08% or more and 0.2% or less. Further, (E) Rosemary extract is 0.004% or more, further 0.008% or more, and further 0.01% as an extract (no solvent) in the whole amount of the pet food of the present invention from the viewpoint of antioxidant effect. % Or more is preferable. From the viewpoint of flavor, it is preferably 5% or less, more preferably 3% or less in pet food.

  When lecithin and rosemary extract are blended into a composition containing fat and minerals containing highly unsaturated fatty acids as constituent fatty acids alone, the antioxidant effect is low and the antioxidants of the system not containing mineral components It does not reach the power. Further, even when lecithin and rosemary extract are used in combination, the antioxidant effect is still not high (see FIG. 1). On the other hand, in the system containing 1.0% or more of citric acid alone, the antioxidant power is restored to the level of the system containing no mineral component. In the present invention, citric acid is contained 10 times or more in a molar ratio with respect to the mineral component in the composition, and the lecithin and the rosemary extract are allowed to coexist, so that it cannot be imagined from the effects of each of them alone. It has been found that the antioxidant power is improved to the level. In fact, when mixed tocopherol, another commonly known antioxidant, and δ-tocopherol, which is said to be very effective, coexist with citric acid, it is more antioxidant than citric acid alone. A phenomenon in which the force decreased was observed (FIG. 1). That is, it can be said that this improvement in antioxidant power is a unique phenomenon by combining a predetermined amount of citric acid with lecithin and rosemary extract.

  The pet food of the present invention contains 0.1 to 10%, further 0.3 to 5%, and further 0.5 to 3% as a total amount of (D) lecithin and (E) rosemary extract. From the viewpoint of achieving both an antioxidant effect and flavor.

  The pet food of the present invention preferably has a pH of 3.5 to 7.0. Within this range, oxidation of the component (A) by the component (B) is more effectively suppressed, and the palatability is also improved. It is preferable that the pH is 4.0 to 7.0, more preferably 4.5 to 6.8, since the effect of suppressing oxidation is further enhanced and the odor during storage is improved. In order to include citric acids and make the pH within such a range, there is a method of adding a pH adjusting agent in addition to citric acid. Among such methods, a method using citric acid and citrate in combination is preferable because it is easy to adjust the pH, has good palatability, and has a uniform taste. In particular, it is preferable to use the above-mentioned alkali metal citrate as the citrate.

In addition, "pH of pet food" means pH when pet food is measured by the following method.
<Method for measuring pH of pet food>
Qualitative filter paper (10 g of pet food) was added to 60 mL of ion exchange water at 45 ° C. (preferably ion exchange water having an electric conductivity of 0.01 mS / m or less at 25 ° C.) and allowed to stand for 1 hour. No. 1, manufactured by Advantec) and the pH of the filtrate was measured at 25 ° C.
In addition, when the property of pet food is solid, it is preferable to perform the said stirring operation after grind | pulverizing finely using a mortar etc.

  The pet food of the present invention preferably further contains a carbohydrate. Examples of the carbohydrate source include monosaccharides, oligosaccharides, polysaccharides, dietary fibers, and starches. Starches include waxy corn starch, corn starch, wheat starch, rice starch, glutinous rice starch, potato starch, honeydew starch, tapioca starch, sago starch, or those that have been chemically treated or chemically modified. Can be mentioned. Carbohydrates may be contained as cereals, and examples of cereals include corn, barley, wheat, rye, sorghum, rice, fin, awa, amarasansus, quinoa and the like. Carbohydrate content in pet food is 10-70%, further 20-60%, and further 30-50%, making the health, health and beauty of anti-obesity effect, ingestion, stool condition and appearance. It is preferable from the point.

In the pet food of the present invention, it is preferable that animal or vegetable protein is further included from the viewpoint of obesity prevention effect, ingestion, nutritional balance, and health and beauty. Sex proteins are more preferred. Examples of animal protein include milk protein such as casein, but animal meat protein is preferable from the viewpoint of obesity prevention effect and ingestion. Such animal meat proteins include cattle, pigs, sheep, rabbits, kangaroos and other meats and beef, and by-products and processed products thereof; chicken, turkey, quail and other meats and by-products and houses. Articles: Fish meat such as fish and white fish, and by-products and processed products thereof; lettering of the above raw materials such as meat meal, meat bones, chicken meal, portary meal, fish meal, and the like. Among these, chicken and fish are particularly preferable from the viewpoint of preventing obesity. When mixing and using several meat protein, it is preferable to contain 30-100% of chicken and / or fish meat in meat, and also 50-100%.
As the vegetable protein, soybean protein, wheat protein, wheat gluten, corn gluten and the like are preferable.

  In the pet food of the present invention, the animal or vegetable protein is preferably contained in an amount of 5 to 70%, further 10 to 60%, and further 15 to 40% in terms of loss on drying.

  The pet food of the present invention may further contain a plant sterol. The plant sterol is preferably contained in the pet food in an amount of 0.1% or more, and more preferably 0.5% or more in terms of cholesterol lowering effect. Moreover, the upper limit of plant sterol content should just be the range of 0.1 to 30%. Examples of plant sterols include free forms such as α-sitosterol, β-sitosterol, stigmasterol, campesterol, α-sitostanol, β-sitostanol, stigmasteranol, campestanol, and cycloartenol, and the like. And fatty acid esters, ferulic acid esters, cinnamic acid esters and the like.

  The pet food of the present invention can further contain bran, potatoes, vegetables, vitamins and the like. As rice bran, rice bran, bran or the like is used, and as rice cake, soybean meal is used. Examples of vegetables include vegetable extracts. Examples of vitamins include A, B1, B2, D, E, niacin, pantothenic acid, carotene and the like, preferably 0.05 to 10%. In addition, a gelling agent, a shape-retaining agent, a pH adjuster, a seasoning, an antiseptic, a nutrition reinforcing agent and the like that are generally used in pet foods can also be contained.

  The pet food of the present invention can be produced by mixing the above ingredients into a desired form, but the fat component of component (A) is preferably added last. For example, citric acid and citrate are mixed together with grains, meat meal, and mineral components such as iron and copper, and after sufficient mixing, they are extruded by an extruder while being hydrated with water or steam. Thereafter, it is preferably dried with hot air until the water content becomes 10% or less. It is desirable to coat fats and oils whose double bonds are rich in two or more fatty acids after drying with hot air. Lecithin and catechin may be added together with citric acid or the like, or may be added together with fats and oils.

  In addition, the pet food of the present invention may be in any form such as dry type, wet type, semi-moist type, jerky type, biscuit type, gum type, granular, powdery, soup, etc. Is preferable from the viewpoint of easy storage. Usually, in the case of a dry type, a plurality of times of pet food is contained in a laminate package. However, after opening, the environment is easy to come into contact with air, so that oxidation tends to proceed. Therefore, it can be said that the pet food of the present invention is more effective in the dry type.

Examples of dry-type pet foods include kibble shapes, flat plate shapes, and bone shapes. From the standpoint of obtaining pets that are easily chewable and easy to handle, the bulk density is preferably 100 to 900 kg / m ³ , particularly 300 to 700 kg / m ³ . However, with such a bulk density, the surface area is increased and a large number of voids are likely to be present on the surface, so it can be said that the oxidation of fats and oils in pet food is likely to proceed. However, even in such a case, since the pet food of the present invention has a high antioxidant power, it is possible to take advantage of the advantages described above. For this reason, it is excellent in the palatability of a pet, a flavor etc. do not deteriorate over a long period of time, and can also receive the benefit of the desired physiological effect resulting from a highly unsaturated fatty acid.

<Preparation of sample>
(A) Oil and fat shown in Table 1, (B) Mineral component, (C) Citric acid + Sodium citrate (mass ratio 1: 2; hereinafter referred to as citric acid mixture), (D) Lecithin, (E) Rosemary extraction Various combinations of the product, (X) and other antioxidants were tested. Test (A) 3 g of fat or oil, or (D) lecithin, (E) rosemary extract, (X) other antioxidants, (B) mineral components, (C) a small amount of citric acid mixture A solution dissolved in water was added.

Details of the materials used in the test are as follows.
(A) Fat and oil: The fatty acid composition is as shown in Table 2.
(B) Mineral component Ferric chloride: Reagent, manufactured by Wako Pure Chemical Co., Ltd. Cupric chloride: Reagent, manufactured by Wako Pure Chemical (C) Citric acid mixture Sodium citrate (dihydrate): Reagent, manufactured by Wako Pure Chemical Co., Ltd. Acid (anhydrous): Reagent, Wako Pure Chemicals (D) Soybean lecithin YELKIN TS (product name, manufactured by AGM, phospholipid equivalent (effective amount) 63.3%)
(E) Rosemary extract Harbarox HT-OC (product name, manufactured by Kalsec Inc, rosemary extract content 40%)
(X) Other antioxidants δ-tocopherol: manufactured by Tama Seikagaku Co., Ltd. mixed tocopherol: mixed tocopherol MTS-60S (product name, manufactured by Archer Daniels Midland Company)

<Method for evaluating antioxidants>
The prepared sample is attached to an automatic oil and fat stability test apparatus (“Rancimat 743”, manufactured by Metrohm), kept at 120 ° C. while bubbling air under the condition of 20 mL / min, and the electrical conductivity is measured. The electrical conductivity against time is plotted, and the rise time (unit: time) is obtained as shown in FIG. 1 to evaluate the stability. This is an evaluation based on the principle that electrical conductivity increases due to oxidation, and a long rise time means high resistance to oxidation.

Test Example Table 3 and FIG. 2 show the test results when (C) citric acid mixture, (D) lecithin, (E) rosemary extract, and (X) other oxidizing agents were used as antioxidants. The results of the rancimat test were evaluated as follows.
<How to read Rancimat rise time>
The effect of the antioxidant was determined based on whether the rise time was extended as compared with the composition before adding the antioxidant. In addition, from the experience so far, it is considered that the fat and oil used in the pet food preferably has a rising time of rancimat (hereinafter referred to as a rising time) of 3 hours or more, so this was evaluated as a preferable composition.

  From the results shown in Table 3 and FIG. 2, in the coexisting system of citric acid, lecithin and rosemary extract (test number 15-18), oil and fat added with minerals (test number 2) and citric acid added thereto Compared with (Test No. 3-5), the rise time in the Rancimat test was greatly improved, and in all cases, the rise time exceeded 3 hours. That is, it can be seen that the composition of the present invention exhibits high antioxidant power in a system containing a large amount of fats and minerals containing a large amount of unsaturated fatty acids as components. In particular, when compared to citric acid shown in Test Nos. 11 and 12, tocopherol, which is a well-known antioxidant, is highly effective.

<Evaluation of antioxidant power in pet food (1)>
Examples 1-3, Reference Examples and Comparative Examples 1-2
A columnar pet food (kibble) having a diameter of 10 mm and a length of about 10 mm was manufactured by mixing extrusion molding with an extruder using raw materials having the composition shown in Table 4. The bulk density was 472 kg / m ³ .

  Tables 5 to 7 show the glyceride or fatty acid composition of fats and oils extracted from the pet foods of Examples 1 to 3, Reference Examples and Comparative Examples 1 and 2, the two double bonds, and the unsaturated fatty acid content having three or more. Show. The total fat and oil contained in the pet food was 15%.

<Stability test method>
As stability test evaluation, evaluation was performed based on the POV (peroxide number) of fats and oils and the amount of oxygen consumed before and after storage.

<Measurement method of POV (peroxide value)>
For the peroxide value (POV) of fats and oils contained in pet food, before storage and at the storage (room temperature: about 20 ° C.) 12 weeks, 2.4. The analysis was performed according to the following procedure according to 12.2-94 “Peroxide Value”.
(1) Extraction of fats and oils from pet food 50 g of kibble was pulverized, passed through a 1 mm sieve, the sample was filled into a cylindrical filter paper, and set in an open column with a cock. With the cock closed, 150 mL of diethyl ether was dropped from above with a dropping funnel, and after completion of dropping, the column cock was opened to collect diethyl ether. Next, the same operation was performed with 50 mL diethyl ether. The recovered diethyl ether was removed by an evaporator to obtain an extracted fat from pet food.
(2) POV measurement of fats and oils 0.5 g of fats and oils extracted from pet food were weighed into a 250 ml tall beaker, and 20 ml of a solution of acetic acid / isooctane = 3/2 (volume ratio) was dissolved. 0.1 mL of saturated potassium iodide solution was added to the tall beaker and shaken well for 1 minute. Thereafter, 30 mL of distilled water was added to obtain a titration sample. The titration sample was titrated with 0.01N sodium thiosulfate. At this time, a POV automatic titrator, DMP Titorino 785 type, manufactured by Metrohm Shibata Co., Ltd. was used.
(3) Evaluation of antioxidant effect In order to evaluate the antioxidant property of pet food, the difference in POV values before and after storage was determined as the POV increase value. The results are shown in Table 4. The lower the POV increase value, the higher the antioxidant property of the pet food.

<Measurement method of oxygen consumption>
A pet food was weighed and sealed with a packaging material laminated with aluminum and stored in a constant temperature bath at 40 ° C. The oxygen concentration X _t (%) in the air was measured every week to calculate the oxygen reduction rate. First, the volume V (mL) of air present in the packaging material was measured, and the oxygen consumption per 50 grams of pet food was determined by the following calculation.
Oxygen consumption (mL) = V · (20.8−X _t ) / 100
The relationship between the storage period and oxygen consumption was measured, and it was found that there was a very good linear relationship. The slope of the straight line was used as an indicator of the stability of pet food, and the results are shown in Table 4.

<Method of measuring citric acid equivalent value>
Add 5 mL of 5% perchloric acid to kibble (3.0 g) crushed with a mixer and shake for 10 minutes. After shaking, the volume is adjusted with a 50 mL volumetric flask. Ultrasonic treatment is performed for 10 minutes, and measurement is performed by a high performance liquid chromatograph (HPLC) method using the filtered solution. The HPLC measurement conditions are as follows.
Column: 2 Shodex Rspak KC-811, diameter 8mm x length 300mm (made by Showa Denko KK)
Column temperature: 40 ° C
Mobile phase: 3 mmol / L perchloric acid aqueous solution Reaction solution: 0.2 mmol / L bromothymol blue-containing 15 mmol / L disodium hydrogen phosphate aqueous solution Flow rate: mobile phase 1.0 mL / min, reaction solution 1.4 mL / min Measurement wavelength : 445 nm

  From the results of Table 4, it can be seen that in the three-component system of citric acid, lecithin and rosemary extract, the POV increase value and the oxygen consumption amount are reduced, and the oxidation stability is remarkably improved. Therefore, in the composition of the present invention, it is possible to stably maintain the effect of pet food that contains a large amount of unsaturated fatty acids that are physiologically promising such as ω3 and ω6 over a long period of time.

Claims (10)

A pet food containing the following components (A) to (E).
(A) an oil or fat containing an unsaturated fatty acid having two or more double bonds as a constituent fatty acid,
(B) Mineral component selected from iron, iron compound, copper and copper compound,
(C) citric acid and / or salt thereof, the total amount is 10 times or more of component (B) in molar ratio,
(D) Lecithin (E) Rosemary extract   The pet food according to claim 1, wherein the content of the component (D) is 0.06 to 6.0 mass% in the pet food.   Pet food of Claim 1 or 2 whose content of the said component (E) is 0.04 mass% or more in pet food.   The pet food according to any one of claims 1 to 3, wherein the citrate is an alkali metal citrate.   The pet food according to any one of claims 1 to 4, wherein the component (C) contains both citric acid and citrate.   The pet food according to any one of claims 1 to 5, wherein the component (A) is an oil containing 3% by mass or more of an unsaturated fatty acid having 3 or more double bonds as a constituent fatty acid.   The pet food according to any one of claims 1 to 6, which has a pH of 3.5 to 7.0.   The pet food according to any one of claims 1 to 7, comprising phosphatidylethanolamine as the component (D), the content of which is 0.03% by mass or more in the pet food.   The pet food according to any one of claims 1 to 8, which is a dry type. (A) In a composition containing an oil or fat containing an unsaturated fatty acid having two or more double bonds as a constituent fatty acid, (B) a mineral component selected from iron, an iron compound, copper and a copper compound, (C) Citric acid and / or a salt thereof, the total amount of which is 10 times or more of component (B) in a molar ratio, (D) lecithin, and (E) rosemary extract, Antioxidation method.

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