JP7775825B2 - Processed foods containing animal and vegetable fats - Google Patents

Description

The present invention relates to processed foods containing animal and vegetable fats. The present invention further relates to a method for producing processed foods containing animal and vegetable fats, a method for inhibiting clouding in processed foods containing animal and vegetable fats, and an agent for inhibiting clouding in processed foods containing animal and vegetable fats.

Processed foods containing animal or vegetable fats (solid fats) can become white (cloudy) due to the solid fats when they are slowly cooled or left to cool after heating, such as baking, resulting in poor appearance and taste. For example, Patent Document 1 describes a method of adding an emulsifier made of a specific polyglycerol fatty acid ester to solid fat foods such as margarine and chocolate to prevent whitening.

On the other hand, in the case of processed meat foods, it has been reported that lipase is added to produce processed meat foods that are juicier without compromising flavor (Patent Document 2).

JP 2010-279267 A JP 2018-102297 A

The technology described in Patent Document 1 was insufficient in suppressing the cloudiness that occurs after heat treatment of processed foods containing animal and vegetable fats, and there was room for improvement.

The present invention has been made in consideration of the above and aims to provide processed foods containing animal and vegetable fats that can suppress cloudiness after heat treatment.

As a result of extensive research into resolving the above-mentioned problems, the inventors discovered that the above-mentioned problems can be solved by adding lipase to the production of processed foods containing animal and vegetable fats and adjusting the amount of monoacylglycerol per gram of lipid in the food to a specific range, thereby completing the present invention.

That is, the present invention includes the following.
[1] A processed food containing animal or vegetable fat, the food containing 0.5 mg to 50 mg of monoacylglycerol per 1 g of lipid in the food.
[2] The processed food containing animal and vegetable fats according to [1], further comprising 5 mg to 125 mg of diacylglycerol per 1 g of lipid in the food.
[3] A processed food containing animal and vegetable fats according to [1] or [2], wherein the ratio (A) of the amount of monoacylglycerol (mg) to the amount of diacylglycerol (mg) per 1 g of lipid in the food is less than 0.2.
(A): Monoacylglycerol amount/(monoacylglycerol amount+diacylglycerol amount)
[4] The food according to any one of [1] to [3], which is a processed meat food.
[5] A method for producing a processed food containing animal and vegetable fats, comprising adding lipase to the raw materials of the processed food containing animal and vegetable fats, and adjusting the amount of monoacylglycerol per 1 g of lipid in the food to 0.5 mg or more and 50 mg or less.
[6] The method according to [5], further comprising adjusting the amount of diacylglycerol per 1 g of lipid in the food to 5 mg or more and 125 mg or less.
[7] The method according to [5] or [6], further comprising adjusting the ratio (A) of the amount of monoacylglycerol (mg) to the amount of diacylglycerol (mg) per 1 g of lipid in the food to less than 0.2.
(A): Monoacylglycerol amount/(monoacylglycerol amount+diacylglycerol amount)
[8] The method according to any one of [5] to [7], wherein the processed food containing animal or vegetable fat is a processed meat food.
[9] A method for suppressing cloudiness of processed foods containing animal and vegetable fats, comprising adding lipase to the raw materials of the processed foods containing animal and vegetable fats, and adjusting the amount of monoacylglycerol per 1 g of lipid in the food to 0.5 mg to 50 mg.
[10] The method according to [9], further comprising adjusting the amount of diacylglycerol per 1 g of lipid in the food to 5 mg or more and 125 mg or less.
[11] The method according to [9] or [10], further comprising adjusting the ratio (A) of the amount of monoacylglycerol (mg) to the amount of diacylglycerol (mg) per 1 g of lipid in the food to less than 0.2.
(A): Monoacylglycerol amount/(monoacylglycerol amount+diacylglycerol amount)
[12] A lipase-containing agent for suppressing clouding of processed foods containing animal and vegetable fats.
[13] The clouding inhibitor according to [12], which is added to a processed food containing animal or vegetable fat so that the content of monoacylglycerol per 1 g of lipid in the processed food containing animal or vegetable fat is 0.5 mg or more and 50 mg or less.
[14] The clouding inhibitor according to [12] or [13], further comprising an emulsifier.

According to the present invention, it is possible to provide processed foods containing animal and vegetable fats that can suppress cloudiness after heat treatment.

Figure 1 shows plots of turbidity versus the amount of monoacylglycerol (MAG) (mg/g) in lipids, with Figure 1(a) showing a linear regression line and Figure 1(b) showing a quadratic regression curve. Figure 2 is a plot of turbidity versus the amount of diacylglycerol (DAG) (mg/g) in lipids, where Figure 2(a) shows a linear regression line and Figure 2(b) shows a quadratic regression curve.

<Terminology>
In the present invention, "animal and vegetable fats" means both animal fats and vegetable fats that are solid at 20°C, and examples thereof include lard, beef fat, chicken fat, rabbit fat, mutton fat, horse fat, milk fat (butter, ghee, etc.), cacao butter, peanut fat, palm oil, palm kernel oil, coconut oil, and hardened oils (margarine, shortening, etc.).

In the present invention, "processed food containing animal and vegetable fats" means processed food containing animal and vegetable fats.

In the present invention, "processed foods" refer to foods prepared by subjecting ingredients to some form of processing, and examples include fish paste products, processed meat products, processed dairy products, processed vegetable products, processed fruit products, oily foods, luxury foods, seasonings, confectioneries, frozen foods, retort foods, canned foods, bottled foods, and instant foods.

In this invention, "processed meat foods" refers to foods prepared by processing meat from livestock such as beef, pork, horse, sheep, goat, and rabbit; poultry such as chicken, duck, wild duck, turkey, domestic duck, quail, guinea fowl, and goose; wild animal meat obtained by hunting such as boar and deer; and marine mammal meat such as whale, dolphin, and sea lion. "Meat" refers to meat that is intended for consumption. Therefore, of the processed foods mentioned above, foods prepared by processing meat, such as processed meat products and frozen foods, retort foods, canned foods, and bottled foods prepared by processing meat, fall under the category of "processed meat foods."

In the present invention, "lipid" refers to an organic compound that is substantially insoluble in water and soluble in organic solvents, and is a general term for fats and oils (triacylglycerol, diacylglycerol, and monoacylglycerol), fatty acids, phospholipids, glycolipids, and sterols.

The present invention will be described in detail below based on preferred embodiments. The present invention is not limited to the following description, and each component can be modified as appropriate without departing from the spirit of the present invention.

[Processed foods containing animal and vegetable fats]
The animal and vegetable fat-containing processed food of the present invention (hereinafter also referred to simply as "food of the present invention") is characterized by containing 0.5 mg to 50 mg of monoacylglycerol (hereinafter also referred to as "MAG") per 1 g of lipid in the food, thereby suppressing cloudiness of the food of the present invention after heat treatment.

Processed foods containing animal and vegetable fats can become white (cloudy) due to the crystallization of the animal and vegetable fats during the slow cooling or natural cooling process after heat treatment, resulting in poor appearance and taste. While techniques have been reported to mitigate the cloudiness problem by adding emulsifiers to physically suppress the crystallization of solid fats, these techniques are not sufficient to prevent the cloudiness that occurs after heat treatment in processed foods containing animal and vegetable fats (particularly processed foods containing animal fats that are prone to crystallization with high melting points), and there is room for improvement.

In contrast, the inventors have discovered that adding lipase to processed foods containing animal fats, which are prone to and difficult to resolve, can dramatically suppress clouding after heat treatment. While emulsifiers physically prevent solid fats from aggregating and crystallizing while maintaining their molecular structure, lipases deesterify solid fats, altering their molecular structure. The inventors hypothesized that this change in the molecular structure of solid fats contributes to suppressing clouding after heat treatment in processed foods containing animal and vegetable fats. Based on this, the inventors investigated the amount and composition of lipids in processed foods containing animal and vegetable fats after the addition of lipase. They found that the amount of MAG in lipids correlates with clouding after heat treatment, and that clouding after heat treatment can be sufficiently suppressed when the MAG amount is within a specified range. The inventors also found that a specific range of MAG in lipids can suppress weight loss associated with heat treatments such as baking, thereby achieving good yields. In this way, the present invention achieves both the suppression of cloudiness after heat treatment and the improvement of yield in processed foods containing animal and vegetable fats, and significantly contributes to the productive production of high-quality processed foods containing animal and vegetable fats.

From the perspective of creating processed foods containing animal and vegetable fats that can suppress clouding after heat treatment, the amount of MAG in the food is 0.5 mg or more per 1 g of lipid in the food, and preferably 1 mg or more, 1.5 mg or more, 2 mg or more, 2.5 mg or more, or 3 mg or more. In particular, an amount of MAG of 3 mg or more per 1 g of lipid in the food is preferable because it can significantly suppress clouding after heat treatment. The amount of MAG per 1 g of lipid in the food is more preferably 4 mg or more, 5 mg or more, 6 mg or more, or 7 mg or more.

As described in detail in the Examples, the inventors have discovered that in order to suppress clouding of processed foods containing animal and vegetable fats after heat treatment, it is not necessarily the case that a high amount of MAG in the lipids is preferable, but that there is an optimal range (see Figure 1). From the perspective of realizing processed foods containing animal and vegetable fats that can suppress clouding after heat treatment, the upper limit of the amount of MAG per gram of lipid in the food is 50 mg or less, and preferably 45 mg or less, 40 mg or less, 35 mg or less, or 30 mg or less. A MAG amount of 30 mg or less per gram of lipid in the food is particularly preferable, as it can further suppress clouding after heat treatment. The MAG amount is more preferably 25 mg or less or 20 mg or less. A MAG amount of 20 mg or less per gram of lipid in the food is particularly preferable, as it can significantly suppress clouding after heat treatment.

Therefore, in one preferred embodiment, a processed food containing animal or vegetable fats contains 0.5 mg or more and 50 mg or less of MAG per 1 g of lipid in the food.

The amount of MAG per 1 g of lipid in processed foods containing animal and vegetable fats can be measured using the method described in the section "(2) Composition analysis of MAG and DAG" below.

The inventors have also discovered that in order to suppress clouding of processed foods containing animal and vegetable fats after heat treatment, in addition to the MAG amount being within the above range, it is preferable that the amount of diacylglycerol (hereinafter also referred to as "DAG") be within the following range.

From the perspective of creating processed foods containing animal and vegetable fats that can suppress clouding after heat treatment, the amount of DAG in the food is preferably 5 mg or more, more preferably 10 mg or more, 15 mg or more, or 20 mg or more per gram of lipid in the food. It is preferable that the amount of MAG is within the above range and the amount of DAG per gram of lipid is 20 mg or more, as this further suppresses clouding after heat treatment. The amount of DAG is even more preferably 25 mg or more, 30 mg or more, 35 mg or more, or 40 mg or more.

As with MAG content, the inventors have discovered that there is an optimal range for DAG content to suppress clouding after heat treatment of processed foods containing animal and vegetable fats (see Figure 2). From the perspective of creating processed foods containing animal and vegetable fats that can suppress clouding after heat treatment, the upper limit of DAG content per gram of lipid in the food is preferably 125 mg or less, and more preferably 120 mg or less, 110 mg or less, 100 mg or less, or 90 mg or less. A DAG content of 90 mg or less per gram of lipid in the food is particularly suitable, as it can further suppress clouding after heat treatment. The DAG content is even more preferably 85 mg or less or 80 mg or less.

The amount of DAG per 1 g of lipid in processed foods containing animal and vegetable fats can be measured using the method described in the section "(2) Composition analysis of MAG and DAG" below.

The inventors have further discovered that in order to suppress clouding of processed foods containing animal and vegetable fats after heat treatment, it is preferable that the MAG and DAG contents are within the above ranges, and that the ratio (A) of the MAG and DAG contents is within a specific range.
Ratio (A): MAG amount/(MAG amount + DAG amount)

From the perspective of creating processed foods containing animal and vegetable fats that can suppress clouding after heat treatment, the ratio (A) of the amount of MAG to the amount of DAG per gram of lipid in the food is preferably 0.9 or less, more preferably 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, 0.2 or less, or less than 0.2. A ratio (A) of less than 0.2 is particularly preferred because it can further suppress clouding after heat treatment. The lower limit of ratio (A) is not particularly limited as long as the amount of MAG is within the above range, but it can be 0.01 or more, 0.02 or more, 0.03 or more, or 0.05 or more.

As long as the amount of MAG per gram of lipid in processed foods containing animal or vegetable fats is within the above range, the amount of free fatty acids is not particularly limited.

As mentioned above, to produce the animal and vegetable fat-containing processed food of the present invention, in which the MAG content, etc., is within the above-mentioned range, lipase is added to the raw materials of the food.

Lipases are enzymes that have the ability to hydrolyze ester bonds in animal and vegetable fats, and include, for example, triacylglycerol lipase, triacylglyceride lipase, etc.

Lipases of various origins are known, including microbial, plant, and animal-derived lipases. In the present invention, the origin is not particularly limited as long as the effects of the present invention are achieved; lipases of any origin can be used, and recombinant enzymes may also be used. Microbial lipases are particularly preferred, including lipases derived from bacteria of the genus Alcaligenes, fungi of the genus Penicillium, fungi of the genus Candida, fungi of the genus Aspergillus, and fungi of the genus Rhizopus.

In the present invention, commercially available lipases provided by various companies can be used, such as Lipase QLM (derived from bacteria of the genus Alcaligenes, manufactured by Meito Sangyo Co., Ltd.), Lipase PL (derived from bacteria of the genus Alcaligenes, manufactured by Meito Sangyo Co., Ltd.), Lipase R (derived from Penicillium roqueforti, manufactured by Amano Enzyme Inc.), Lipase A (derived from Aspergillus niger, manufactured by Amano Enzyme Inc.), and Lipase AY (derived from fungi of the genus Candida, manufactured by Amano Enzyme Inc.).

The animal and vegetable fat-containing processed foods of the present invention are not particularly limited in type, as long as they contain animal and vegetable fats, and broadly encompass the processed foods described above. In particular, processed foods with a high animal and vegetable fat content are preferred from the perspective of better enjoying the effects of the present invention. For example, processed foods with an animal and vegetable fat content of 10% by weight or more, 20% by weight or more, 25% by weight or more, or 30% by weight or more are preferred, assuming the total weight of the food to be 100% by weight. The upper limit of the animal and vegetable fat content in animal and vegetable fat-containing processed foods is not particularly limited, but is typically 70% by weight or less, preferably 60% by weight or less, 55% by weight or less, or 50% by weight or less. The present invention is advantageous because it can suppress cloudiness after heat treatment, even in processed foods with a high content of animal and vegetable fats.

Among these, processed meat foods, cooked foods (frozen foods, retort foods, canned foods, bottled foods that do not fall under the category of processed meat foods), and confectioneries are particularly suitable as processed meat foods and cooked foods (e.g., processed meat foods and cooked foods that are easily affected by the cloudiness of animal and vegetable fats), and suitable processed meat foods and cooked foods include, for example, hamburger steaks and hamburger steak-like foods, meatballs and meatball-like foods, gyoza and gyoza-like foods, and shumai and shumai-like foods. Suitable confectioneries include, for example, chocolate and chocolate-containing confectioneries.

The ingredients for processed foods containing animal and vegetable fats may be selected appropriately depending on the type and specifications of the processed food, and are not particularly limited as long as at least some of the ingredients contain animal and vegetable fats. Ingredients containing animal and vegetable fats include animal and vegetable fats themselves, as well as animal fat-containing ingredients such as pork, beef, chicken, rabbit, mutton, horsemeat, and raw milk, and vegetable fat-containing ingredients such as cacao, peanuts, palm pulp and kernel, and coconut pulp and kernel.

Other ingredients include, for example, protein ingredients such as dried egg white and gluten flour; starchy ingredients such as bread, wheat flour, rice, oatmeal, cornmeal, and vermicelli; thickeners such as methylcellulose, propylene glycol alginate, and sodium polyacrylate; binders such as phosphates (monosodium phosphate, dipotassium phosphate, etc.) and polymerized phosphates (sodium polyphosphate, sodium metaphosphate, etc.); preservatives such as sodium nitrite and sorbic acid; antioxidants such as sodium L-ascorbate and catechin; pH adjusters such as fumaric acid; sucrose fatty acid esters, polyglycerin fatty acid esters, saponin, lecithin, calcium carbonate, etc. Examples of such additives include emulsifiers such as sodium zeinate; seasonings such as salt, soy sauce, and umami seasonings (such as monosodium L-glutamate and sodium inosinate); flavorings such as beef flavor, onion powder, garlic powder, pepper, and sage; colorings such as caramel color, annatto color, and cochineal color; nutritional enhancers such as vitamins (such as L-ascorbic acid, ergocalciferol, and β-carotene), minerals (such as zinc salts, calcium chloride, and ferric chloride), and amino acids (such as sodium L-aspartate, DL-alanine, L-arginine, and L-isoleucine); and other enzymes such as transglutaminase. These may be used alone or in combination of two or more.

[Method of manufacturing processed foods containing animal and vegetable fats]
The present invention also provides a method for producing a processed food containing animal and vegetable fats (hereinafter also simply referred to as the "production method of the present invention").

The manufacturing method of the present invention is characterized by adding lipase to the raw materials of processed foods containing animal and vegetable fats, and adjusting the amount of monoacylglycerol (MAG) per 1 g of lipid in the food to 0.5 mg or more and 50 mg or less.

The ingredients and lipases of animal and vegetable fat-containing processed foods, the amounts of MAG and diacylglycerol (DAG) in the animal and vegetable fat-containing processed foods, the preferred range of the ratio (A) of MAG to DAG, and the animal and vegetable fat-containing processed foods are as described above in the "Animal and vegetable fat-containing processed foods" section. For example, from the perspective of realizing an animal and vegetable fat-containing processed food that can further suppress cloudiness after heat treatment, it is particularly preferable to set the MAG amount per gram of lipid in the food to 3 mg or more and 30 mg or less. Furthermore, from the perspective of realizing an animal and vegetable fat-containing processed food that can further suppress cloudiness after heat treatment, in addition to setting the MAG amount within a specific range, it is particularly preferable to set the DAG amount per gram of lipid to 5 mg or more and 125 mg or less (more preferably 20 mg or more and 90 mg or less), and to set the ratio (A) of MAG to DAG amount (i.e., [MAG amount/(MAG amount + DAG amount)]) to less than 0.2. From the viewpoint of being able to enjoy the effects of the present invention to a greater extent, processed foods containing animal and vegetable fats are preferably processed foods with a high content of animal and vegetable fats (processed foods with an animal and vegetable fat content of preferably 10% by weight or more, 20% by weight or more, 25% by weight or more, or 30% by weight or more), and among these, processed meat foods, cooked foods (frozen foods, retort foods, canned foods, bottled foods that do not belong to the category of processed meat foods), and confectioneries are particularly preferred.

In the production method of the present invention, the amount of lipase added is not particularly limited as long as the above-mentioned MAG amount, etc. is achieved. The amount of lipase added is typically 1 U (unit) or more, e.g., 5 U or more, 10 U or more, 20 U or more, 30 U or more, 50 U or more, or 100 U or more, based on enzyme activity, per 1 g of the total weight of the raw materials of the processed food containing animal and vegetable fats (substantially per 1 g of the food). The upper limit of the amount added is not particularly limited as long as the above-mentioned MAG amount, etc. is achieved, and is typically 10,000 U or less, e.g., 9,000 U or less, 8,000 U or less, 7,000 U or less, 6,000 U or less, or 5,000 U or less, per 1 g of food.
The enzymatic activity of lipase can be calculated by, for example, allowing lipase to act on an emulsion of olive oil as a substrate for a certain period of time and quantifying the amount of released fatty acids with alkali. In this specification, 1 U is defined as the amount of enzyme that releases 1 μmol of fatty acids per minute at 37°C.

The above amount of lipase may be added all at once to the raw materials for processed foods containing animal and vegetable fats, or it may be added in small amounts to reach the above amount.

The conditions for adding lipase to the raw material and allowing it to act on the animal or vegetable fat vary depending on the type of animal or vegetable fat and the type of lipase, but the temperature is typically 0°C or higher, preferably 2°C or higher, 3°C or higher, 4°C or higher, or 5°C or higher. The upper limit of the temperature is typically 60°C or lower, preferably 50°C or lower, 40°C or lower, 30°C or lower, or 20°C or lower. The pH is typically in the range of 3 to 11, and preferably 4 to 9.

The manufacturing method of the present invention may further include known processing steps that are typically performed when producing processed foods containing animal or vegetable fats. For example, lipase may be added to the raw materials of the food, and the resulting mixture may be molded or packed into a casing or the like. Other processing steps that may be performed include pickling (salting, miso pickling, soy sauce pickling, etc.), heating (baking, drying, boiling, smoking, braising, temperature adjustment, etc.), and fermentation.

According to the manufacturing method of the present invention, in which lipase is added to raw materials to adjust the MAG content per gram of lipid in the food to a specific range, cloudiness after heat treatment can be suppressed, as described above, and processed foods containing animal and vegetable fats with good appearance and taste can be produced. In addition, the manufacturing method of the present invention can suppress the outflow of lipids during heat treatment, improving yield. Therefore, in a preferred embodiment, the manufacturing method of the present invention includes a step of adding lipase to raw materials for processed foods containing animal and vegetable fats and heating the resulting mixture.

After heat treatment, processed foods containing animal and vegetable fats can be slowly cooled or allowed to stand to cool to room temperature before eating. Processed foods containing animal and vegetable fats produced by the manufacturing method of the present invention can prevent cloudiness caused by animal and vegetable fats during the process of slowly cooling or allowing to stand to cool to room temperature after heat treatment, and can maintain the excellent appearance and taste of freshly made or cooked food.

After heat treatment, the food may be stored at room temperature, or may be cooled (refrigerated) or frozen. When cooling or freezing, the food may be cooled under running water, cooled to approximately 2°C to 10°C in a refrigerator, or flash-frozen to -20°C or below in a freezer. Processed foods containing animal and vegetable fats produced by the manufacturing method of the present invention contribute to reducing cloudiness caused by animal and vegetable fats even during such storage, refrigeration, and freezing processes, and can also suppress cloudiness after heat treatment if the food is heated again before consumption.

As a preferred embodiment of the present invention, a method for producing a processed meat food is described below.
Depending on the specific specifications of the processed meat food, ingredients such as meat, other protein ingredients, starch materials, thickeners, binders, preservatives, antioxidants, pH adjusters, emulsifiers, seasonings, flavorings, colorings, and nutritional enhancers are mixed in a mixer. Lipase is added to the ingredients during this mixing process. The ingredients of the processed meat food may be added to the mixer all at once and mixed, or may be divided into sections, such as a meat section, a binder section containing thickeners and binders, a seasoning section containing seasonings and flavorings, and an other protein section containing other protein ingredients, and then added and mixed separately. When the ingredients are added and mixed separately, lipase may be added after mixing all the sections, or after mixing some of the sections. When lipase is added after mixing some of the sections, the remaining sections may be added and mixed after adding lipase. The resulting mixture is then shaped and subjected to a heat treatment such as steaming or baking.

[Method for suppressing cloudiness in processed foods containing animal and vegetable fats]
The present invention also provides a method for inhibiting clouding of processed foods containing animal and vegetable fats (hereinafter simply referred to as the "clouding inhibition method of the present invention" or "the method of the present invention").

The method for inhibiting cloudiness of the present invention is characterized by adding lipase to the raw materials of processed foods containing animal and vegetable fats, and reducing the amount of monoacylglycerol (MAG) per 1 g of lipid in the food to 0.5 mg or more and 50 mg or less.

The ingredients and lipases of animal and vegetable fat-containing processed foods, the amounts of MAG and diacylglycerol (DAG) in the animal and vegetable fat-containing processed foods, the preferred range of the ratio (A) of MAG to DAG, and the animal and vegetable fat-containing processed foods are as described above in the "Animal and vegetable fat-containing processed foods" section. For example, from the perspective of further suppressing cloudiness in animal and vegetable fat-containing processed foods, it is particularly preferred to set the MAG content per gram of lipid in the food to between 3 mg and 30 mg. Furthermore, from the perspective of further suppressing cloudiness in animal and vegetable fat-containing processed foods, in addition to setting the MAG content within a specific range, it is particularly preferred to set the DAG content per gram of lipid to between 5 mg and 125 mg (more preferably between 20 mg and 90 mg) and to set the ratio (A) of MAG to DAG, i.e., [MAG content/(MAG content + DAG content)], to less than 0.2. From the viewpoint of being able to enjoy the effects of the present invention to a greater extent, processed foods containing animal and vegetable fats are preferably processed foods with a high content of animal and vegetable fats (processed foods with an animal and vegetable fat content of preferably 10% by weight or more, 20% by weight or more, 25% by weight or more, or 30% by weight or more), and among these, processed meat foods, cooked foods (frozen foods, retort foods, canned foods, bottled foods that do not belong to the category of processed meat foods), and confectioneries are particularly preferred.

The conditions for adding lipase to raw materials and allowing it to act on animal and vegetable fats are as explained in the section above titled "Method for producing processed foods containing animal and vegetable fats."

The method of the present invention can suppress clouding of processed foods containing animal and vegetable fats after heat treatment. When processed foods containing animal and vegetable fats are heat-treated without the addition of lipase, the turbidity of the effluent animal and vegetable fat-containing material after a certain time (e.g., 1 hour) has elapsed since the heat treatment is defined as T0. The turbidity T achieved by the clouding suppression method of the present invention is preferably T0 x 0.9 or less, more preferably T0 x 0.8 or less, T0 x 0.7 or less, or T0 x 0.6 or less. Even when producing processed foods containing animal and vegetable fats with high contents of animal and vegetable fats that tend to become significantly cloudy after heat treatment (particularly processed foods containing animal fats with high contents of animal fats that are prone to forming high-melting-point crystals), the method of the present invention can reduce turbidity by the order of 10% or several tens of percent, as described above, thereby suppressing clouding.

[An agent for preventing cloudiness in processed foods containing animal and vegetable fats]
The present invention also provides an agent for inhibiting clouding of processed foods containing animal and vegetable fats (hereinafter, also simply referred to as "the clouding inhibitor of the present invention" or "the agent of the present invention").

The clouding inhibitor of the present invention is characterized by containing lipase.

Regarding lipase and processed foods containing animal and vegetable fats, the details are as explained above in the section titled "Processed Foods Containing Animal and Vegetable Fats." From the perspective of better enjoying the effects of the present invention, processed foods containing animal and vegetable fats are preferably processed foods with a high animal and vegetable fat content (preferably processed foods with an animal and vegetable fat content of 10% by weight or more, 20% by weight or more, 25% by weight or more, or 30% by weight or more), with processed meat foods, cooked foods (frozen foods, retort foods, canned foods, bottled foods that do not fall under the category of processed meat foods), and confectioneries being particularly preferred.

In order to suppress the clouding of processed foods containing animal and vegetable fats, the clouding inhibitor of the present invention is added to processed foods containing animal and vegetable fats by adjusting the amount and conditions of addition so that the monoacylglycerol (MAG) content is 0.5 mg to 50 mg per gram of lipid in the processed foods containing animal and vegetable fats. Therefore, in one embodiment, the clouding inhibitor of the present invention is added to processed foods containing animal and vegetable fats so that the MAG content is 0.5 mg to 50 mg per gram of lipid in the processed foods containing animal and vegetable fats. The preferred ranges for the MAG content, diacylglycerol (DAG) content, and the ratio (A) of the MAG amount to the DAG amount are as explained above in the "Processed foods containing animal and vegetable fats" section, and the amount and conditions of addition of the agent of the present invention are adjusted to satisfy these preferred ranges.

The agent of the present invention may further contain an emulsifier. By including an emulsifier, clouding of processed foods containing animal and vegetable fats can be further suppressed. The emulsifier may be any known emulsifier used in producing processed foods containing animal and vegetable fats, such as sucrose fatty acid esters, polyglycerin fatty acid esters, saponin, lecithin, and sodium caseinate.

The agent of the present invention may further contain other physiologically acceptable ingredients, as long as they do not inhibit the effects of the present invention. Such ingredients include, for example, salts to enhance lipase activity, sugars to improve powder properties in powdered agents, and dispersants such as water in liquid agents.

In the agent of the present invention, the lipase content varies depending on the type and potency of the lipase, but is typically 1% by weight or more, and may be, for example, 2% by weight or more, 3% by weight or more, 4% by weight or more, or 5% by weight or more. The upper limit of the lipase content is not particularly limited, but is typically 99% by weight or less, and may be, for example, 98% by weight or less, 96% by weight or less, 95% by weight or less, 90% by weight or less, or 80% by weight or less.

The present invention will be specifically explained below using examples. However, the present invention is not limited to the examples shown below.

(1) Production of processed food (hamburger steak) containing animal and vegetable fats (a) The lean pork meat shown in Table 1 was placed in a KitchenAid mixer ("KSM5ER (Empire Red)", manufactured by FMI Co., Ltd.) and mixed at first speed for 30 seconds while adding salt. Thereafter, the remaining ingredients and lipase were added and mixed at first speed for 4 minutes, and then at second speed for an additional 1 minute.
(b) The mixture obtained in (a) above was filled into a muffin plate at 30 g/hole and molded. The weight of the muffin plate filled with the molded food product was measured, and the weight M1 (g) of the resulting molded food product was calculated based on the weight of the muffin plate itself.
(c) The muffin plates filled with the food products obtained in (b) above were vacuum packed and kept in a refrigerator at 5°C for 18 hours.
(d) The muffin plate filled with the food product was removed from the packaging and baked in a steam convection oven at 200°C for 9 minutes to produce a hamburger steak. The weight M2 (g) of the baked hamburger steak was measured.

The raw materials used in the production of the hamburger steak are as follows:
- Lean pork, salt, and pork fat were all general food ingredients and products.
The lipases used were various commercially available lipases (A to F) shown in Table 2. For each lipase, the amount added was changed within the range of 100 to 5000 U/g, and three samples were produced (two samples for lipase C) (17 samples in total; Samples No. 1 to 17 in Table 3).

As a control sample, a hamburger steak was produced in the same manner as above, except that no lipase was added (Sample No. 18 in Table 3).

(2) Composition analysis of MAG and DAG <Extraction of lipids from samples>
For each hamburger steak sample, a sample extract was prepared according to the following procedures (i) to (xii).
(i) Approximately 250 mg of the hamburger steak sample obtained in (1) above was precisely weighed into a test tube.
(ii) 1 mL of distilled water, 2.5 mL of methanol, and 1 mL of chloroform were added.
(iii) The mixture was mixed using a vortex mixer and subjected to ultrasonic irradiation for 10 minutes.
(iv) Further, 1.5 mL of chloroform and 1.25 mL of distilled water were added.
(v) The mixture was stirred for 1 minute using a vortex mixer.
(vi) The mixture was centrifuged at 3,000 rpm for 10 minutes, and the lower layer was removed into another test tube.
(vii) 2 mL of chloroform was added to the remaining upper layer.
(viii) The mixture was stirred for 1 minute using a vortex mixer.
(ix) The lower layer was combined with the test tube in (vi).
(x) The contents of the test tube (ix) were evaporated to dryness under a stream of nitrogen.
(xi) 10 mL of chloroform was added to dissolve the product.
(xii) Chloroform was added to dilute the solution five times to obtain a sample extract.

The solution obtained by performing only steps (ii) to (xii) above without using the hamburger steak sample was used as the blank.

<7-component mixed standard stock solution (hereinafter referred to as 7mix STK)>
Monopalmitin, dipalmitin, tripalmitin, monostearin, tristearin, monoolein, and triolein were dissolved and mixed in chloroform to prepare 7mix STK with a concentration of 50 μg/mL for each component.

<Standard solutions and sample solutions>
1 mL of each of the standard stock solution, sample extract, and blank was placed in a GC glass vial, dried under a nitrogen stream, and then redissolved by adding 0.5 mL of pyridine. Next, 0.05 mL of N-methyl-N-trimethylsilyl-trifluoroacetamide (MSTFA) was added, and the mixture was shaken at 37°C for 30 minutes. 0.5 mL of chloroform was added and mixed to obtain the standard solution (STD), sample solution, and blank, respectively.

<Measurement conditions>
The standard solution, sample solution and blank were each measured once.
・GC section Column used: Rtx-65TAG inner diameter 0.25mm x column length 30m, df. 0.10μm (Restek)
Column temperature: 80°C (2 minutes) → 10°C/minute → 360°C (12 minutes)
Injection temperature: 360°C
Interface temperature: 348°C
Carrier gas control mode: Linear velocity constant 49 cm/sec Sample introduction method: Split 1:5
Injection volume: 1μL
MS section Ionization method: EI method Ion source temperature: 300°C
Mode: scan
Mass range: m/z 45-650

(3) Evaluation of turbidity (turbidity) The liquid spilled after baking the hamburger was collected from the muffin plate into a 50 mL Falcon tube. The collected liquid was heated at 60 ° C. to melt the lipid solids, then centrifuged at 4000 g for 10 minutes, and 200 μL of the supernatant was dispensed into a 96-well microplate. After heating the dispensed microplate at 60 ° C. for 2 hours or more, the OD (optical density) measurement at a wavelength of 660 nm at room temperature was immediately started using a microplate reader ("SpectraMax M5", manufactured by Molecular Devices Japan).

(4) Evaluation of yield The yield was calculated using the measured weights M1 and M2 as follows: Three hamburger steaks were produced for each sample, and the yield was calculated by averaging these values.
Yield (%) = 100 x M2/M1

Table 3 summarizes the measurement results for the amount of MAG (mg/g) and DAG (mg/g) in the lipids, turbidity (1 hour after the start of measurement), and yield for each sample. Figure 1 shows a plot of turbidity versus the amount of MAG (mg/g) in the lipids. In detail, Figure 1(a) shows the linear regression line, and Figure 1(b) shows the quadratic regression curve. Figure 2 shows a plot of turbidity versus the amount of DAG (mg/g) in the lipids. In detail, Figure 2(a) shows the linear regression line, and Figure 2(b) shows the quadratic regression curve.

As can be seen from Table 3 and Figure 1, samples with MAG content in the lipids of 0.5 to 50 mg/g, within the range of the present invention, had lower turbidity than the conventional lipase-free sample (Sample No. 18), demonstrating that cloudiness after baking could be suppressed. Comparing the linear regression line in Figure 1(a) with the quadratic regression curve in Figure 1(b) reveals that the relationship between MAG content in the lipids and turbidity is more consistent with quadratic regression than with linear regression (the correlation coefficient R2 is higher for quadratic regression), indicating that there is an optimal range for the MAG content in the lipids to suppress cloudiness after baking. In particular, when the MAG content in the lipids was in the range of 3 to 30 mg/g, the turbidity was below 1, further suppressing cloudiness after baking. In particular, when the MAG content in the lipids was in the range of 3 to 20 mg/g, cloudiness after baking tended to be significantly suppressed. With regard to taste, in samples in which the amount of MAG in the lipid was outside the range of the present invention, a difference was felt between the solidified fat portion and the other food ingredients during mastication, and the strange taste characteristic of the solidified fat remained in the mouth, resulting in a lack of unity in the taste, whereas samples in which the amount of MAG in the lipid was within the range of the present invention (especially samples in which the amount of MAG in the lipid was in the preferred range of 3 to 30 mg/g) presented a good, unity-like taste.Furthermore, it was confirmed that the samples in which the amount of MAG in the lipid was within the range of the present invention also had an improvement in yield on the order of 100% compared to a conventional sample (sample No. 18) to which no lipase was added.

Furthermore, as can be seen from Table 3 and Figure 2, it was confirmed that samples in which the DAG content in the lipids was in the range of 5 to 125 mg/g suppressed cloudiness after baking. Comparing the linear regression line in Figure 2(a) with the quadratic regression curve in Figure 2(b) shows that the relationship between the DAG content in the lipids and turbidity is more consistent with quadratic regression than with linear regression (the correlation coefficient R2 is higher for quadratic regression), indicating that there is an optimal range for the DAG content in lipids to suppress cloudiness after baking. In particular, when the DAG content in lipids was in the range of 20 to 90 mg/g, cloudiness after baking tended to be significantly suppressed.

Furthermore, as can be seen from Table 3, samples in which the amount of MAG in the lipid was within the range of the present invention and the ratio of the amount of MAG to the amount of DAG [MAG/(MAG+DAG)] was less than 0.2 tended to significantly suppress cloudiness after baking.

Claims (14)

A processed meat food containing one or more animal fats selected from lard, milk fat, chicken fat and horse fat, obtained by adding lipase to a raw material for a processed meat food containing one or more animal fats selected from lard, milk fat, chicken fat and horse fat, said food containing 0.5 mg to 30 mg of monoacylglycerol per 1 g of lipid in said food. The processed meat food product according to claim 1, further comprising 5 mg to 125 mg of diacylglycerol per 1 g of lipid in the food. 3. A processed meat food according to claim 1 or 2, wherein the ratio (A) of the amount of monoacylglycerol (mg) to the amount of diacylglycerol (mg) per 1 g of lipid in the food is less than 0.2.
(A): Monoacylglycerol amount/(monoacylglycerol amount+diacylglycerol amount) The food product according to any one of claims 1 to 3, wherein the content of one or more animal fats selected from lard, milk fat, chicken fat, and horse fat is 20% by mass or more. A method for producing a processed meat food product, which comprises adding lipase to a raw material for the processed meat food product containing one or more animal fats selected from lard, milk fat, chicken fat, and horse fat, and adjusting the amount of monoacylglycerol per 1 g of lipid in the food product to 0.5 mg or more and 30 mg or less. The method of claim 5, further comprising adjusting the amount of diacylglycerol per gram of lipid in the food to 5 mg or more and 125 mg or less. The method according to claim 5 or 6, further comprising adjusting the ratio (A) of the amount of monoacylglycerol (mg) to the amount of diacylglycerol (mg) per 1 g of lipid in the food to less than 0.2.
(A): Monoacylglycerol amount/(monoacylglycerol amount+diacylglycerol amount) The method according to any one of claims 5 to 7, wherein the processed meat food contains 20% by mass or more of one or more animal fats selected from lard, milk fat, chicken fat, and horse fat. A method for inhibiting clouding of processed meat foods by adding lipase to the raw materials of processed meat foods containing one or more animal fats selected from lard, milk fat, chicken fat, and horse fat, and adjusting the amount of monoacylglycerol per gram of lipid in the food to 0.5 mg to 30 mg. The method of claim 9, further comprising adjusting the amount of diacylglycerol per gram of lipid in the food to 5 mg or more and 125 mg or less. The method according to claim 9 or 10, further comprising adjusting the ratio (A) of the amount of monoacylglycerol (mg) to the amount of diacylglycerol (mg) per 1 g of lipid in the food to less than 0.2.
(A): Monoacylglycerol amount/(monoacylglycerol amount+diacylglycerol amount) A clouding inhibitor for processed meat foods containing one or more animal fats selected from lard, milk fat, chicken fat, and horse fat, the clouding inhibitor containing lipase being added to the processed meat food so that the monoacylglycerol content per 1 g of lipid in the food is 0.5 mg to 30 mg. The clouding inhibitor according to claim 12, which is added to a processed meat food so that the diacylglycerol content per 1 g of lipid in the processed meat food is 5 mg or more and 125 mg or less. The clouding inhibitor according to claim 12 or 13, further comprising an emulsifier.