Food product and shelf life improver for food product

Abstract

A food product according to the present invention contains either 0.2-2 mass% of sodium acetate and 0.01-0.2 mass% of an organic acid or 0.02-0.2 mass% of acetic acid, contains 0.005-0.5 mass% of liquid smoke, and has a pH of 5.0-7.0 at a product temperature of 25°C. The organic acid preferably contains at least one selected from the group consisting of acetic acid, citric acid, malic acid, fumaric acid, adipic acid, glucono delta lactone, gluconic acid, succinic acid, tartaric acid, ascorbic acid, and lactic acid.

Description

Foods and food shelf-life extenders

[0001] This invention relates to a food product containing organic acids that exhibit bacteriostatic effects.

[0002] Organic acids such as acetic acid and sodium acetate, and their salts (organic acids), are sometimes added to food and beverages to improve their shelf life. Organic acids exhibit a bacteriostatic effect that inhibits the growth of microorganisms, and by adding them to food and beverages, the shelf life of the food is improved. Patent Document 1 describes a rice quality improver that contains organic acids in addition to a heated sugar product, which suppresses the retrogradation of starch in cooked rice, making the cooked rice less prone to retrogradation and dryness even when stored for a long time. The heated sugar product is obtained by heat-treating fructose or a sugar composition containing fructose at 100 to 200°C.

[0003] However, when organic acids are added to food and beverages, they can impart an unpleasant sour taste and odor, impairing the original flavor of the food and beverage. Regarding technologies for reducing, suppressing, or masking the sour taste and odor of food and beverages caused by the addition of such organic acids, that is, technologies for inhibiting the perception of sour taste and odor, Patent Document 2 describes a sour taste masking agent for use in food and beverages containing organic acids, which contains three or more materials selected from at least two of three categories: sugar-treated products, protein-treated products, and plant-treated products. Examples of such sugar-treated products include sugar alcohols, heated palatinose, and dextrin.

[0004] Furthermore, conventionally, for the purpose of imparting savory aroma to food, food has been subjected to smoking treatment. Patent Document 3 describes a flavored oil composition comprising oil and fat A obtained by smoking treatment using roasted wheat as a smoking material and oil and fat B obtained by smoking treatment using cherry chips as a smoking material. It is stated that by adding the flavored oil composition to food, savory aroma can be imparted to the food. Examples of foods to which the flavored oil composition can be applied include stir-fried foods, grilled foods, sauces, soups, processed meat products, cooked rice products, seasonings, and deep-fried foods. Patent Document 4 describes smoked flour obtained by subjecting raw grain flour such as wheat flour to smoking treatment. It is stated that the smoked flour can be used as a coating material when producing heat-cooked foods such as fried chicken and pork cutlets, and can improve the flavor of heat-cooked foods, particularly impart or enhance saltiness. Patent Document 5 describes a flavor improver obtained by treating wheat flour such as wheat flour with a specific fermentation liquid, and describes that liquid smoke is used as an aroma material in the fermentation liquid. It is stated that bread produced using the flavor improver is savory and has good dough properties and crust color.

[0005] Japanese Patent Application Laid-Open No. 2021-61788, Japanese Patent Application Laid-Open No. 2019-8, Japanese Patent Application Laid-Open No. 2024-116681, Japanese Patent Application Laid-Open No. 2021-182869, Japanese Patent Application Laid-open No. 60-251857

[0006] An object of the present invention is to provide a technique capable of improving the storage stability of a food without impairing the inherent flavor of the food.

[0007] As a result of various studies on a technique capable of inhibiting the perception of sour taste and sour odor derived from organic acids having bacteriostatic effects in foods containing the organic acids, the present inventors found that, when a specific amount of wood-derived liquid smoke is blended into a food that contains the organic acids and whose pH is adjusted to a specific range, the perception of the sour taste and sour odor derived from the organic acids can be inhibited while enjoying the effect of inhibiting the growth of microorganisms by the organic acids.

[0008] The present invention has been made based on the above findings, and provides a food containing 0.2 to 2% by mass of sodium acetate and 0.01 to 0.2% by mass of an organic acid, or 0.02 to 0.2% by mass of acetic acid, and 0.005 to 0.5% by mass of liquid smoke, and having a pH of 5.0 to 7.0 at a product temperature of 25°C.

[0009] Furthermore, the present invention is based on the above findings and is a food preservation agent containing 40 to 90% by mass of sodium acetate, 1 to 15% by mass of an organic acid, or 3 to 15% by mass of acetic acid, and 0.25 to 5% by mass of smoke syrup, and the pH of a 1% by mass aqueous solution at a product temperature of 25°C is 4.5 to 6.5.

[0010] Furthermore, the present invention is based on the above findings and is a method for inhibiting the perception of sourness and sour odor in a food containing sodium acetate or an organic acid, the method comprising adding smoke flavoring to the food.

[0011] The food of the present invention includes a form containing sodium acetate and an organic acid (hereinafter also referred to as "first form") and a form containing acetic acid (hereinafter also referred to as "second form"). Sodium acetate, organic acid, and acetic acid mainly function as bacteriostatic agents that suppress the growth of microorganisms such as lactic acid bacteria and food poisoning bacteria, and contribute to improving the shelf life of the food.

[0012] The sodium acetate, organic acid, and acetic acid used in this invention may be any food-grade substances; for example, commercially available food additives can be used. Specific examples of sodium acetate include anhydrous sodium acetate and sodium acetate hydrate. These are solids (powder / granules) at room temperature and pressure. Examples of organic acids include acetic acid, citric acid, malic acid, fumaric acid, adipic acid, glucono delta-lactone, gluconic acid, succinic acid, tartaric acid, ascorbic acid, and lactic acid. These can be used individually or in combination of two or more. Among these, acetic acid, citric acid, and fumaric acid are particularly preferred.

[0013] The sodium acetate content in the first form of food is 0.2 to 2% by mass, preferably 0.3 to 1.8% by mass, and more preferably 0.4 to 1.5% by mass, based on the total mass of the food. The organic acid content in the first form of food is 0.01 to 0.2% by mass, preferably 0.03 to 0.15% by mass, and more preferably 0.05 to 0.1% by mass, based on the total mass of the food. If the sodium acetate content is less than 0.2% by mass, or the organic acid content is 0.01% by mass, a sufficient bacteriostatic effect cannot be obtained, and the food's shelf life cannot be improved. If the sodium acetate content is more than 2% by mass, or the organic acid content is more than 0.2% by mass, an undesirable sour taste and odor caused by sodium acetate and / or organic acids becomes prominent, and the food's inherent flavor may be impaired. The sodium acetate and organic acid content in food can be measured by known analytical methods such as high-performance liquid chromatography.

[0014] The acetic acid content in the second form of food is 0.02 to 0.2% by mass relative to the total mass of the food, preferably 0.04 to 0.15% by mass, and more preferably 0.06 to 0.1% by mass. If the acetic acid content is less than 0.02% by mass, a sufficient bacteriostatic effect cannot be obtained, and the food's shelf life cannot be improved. If the acetic acid content exceeds 0.2% by mass, an undesirable sour taste and odor caused by acetic acid becomes prominent, and the food's inherent flavor may be impaired. The acetic acid content in food can be measured by known analytical methods such as high-performance liquid chromatography.

[0015] The food product of the present invention contains smoke flavorings. The smoke flavorings primarily function as masking agents that inhibit the perception of sour taste and sour odor caused by sodium acetate, organic acids, or acetic acid, thereby contributing to the preservation of the food's inherent flavor. In this specification, "smoke flavorings" refers to a liquid containing smoke components produced when smoking materials are incompletely combusted. Smoke flavorings are typically produced by collecting gaseous components generated by burning wood or non-wood materials (such as sugarcane, bamboo, or corn), or by cooling smoke obtained by dry distillation, and are hydrophilic liquids containing phenols, carbonyl compounds such as aldehydes and ketones, organic acids, esters, etc. The phenols, carbonyl compounds, esters, etc. contained in the smoke flavorings are presumed to be active ingredients that inhibit the perception of sour taste and sour odor caused by organic acids or acetic acid.

[0016] From the viewpoint of further improving the function of the smoke solution as a masking agent, the pH of the smoke solution at a temperature of 25°C is preferably 4.5 to 6.5, and more preferably 5.0 to 6.0.

[0017] Commercially available smoke solutions can also be used. A preferred commercially available smoke solution is "SmokeEz LFBN" (manufactured by Kerry, Inc. (USA), distributed by Wisco International Co., Ltd.).

[0018] The amount of smoke flavoring in the food of the present invention is 0.005 to 0.5% by mass, preferably 0.01 to 0.1% by mass, and more preferably 0.03 to 0.07% by mass, relative to the total mass of the food. If the amount of smoke flavoring is less than 0.005% by mass, there is a risk that the sour taste and odor caused by sodium acetate, organic acids, or acetic acid may not be sufficiently suppressed. If the amount of smoke flavoring is greater than 0.5% by mass, there is a risk that the characteristic flavor of the smoke flavoring in the food will become too strong, resulting in the inherent flavor of the food being impaired. When using commercially available smoke flavoring, it is sufficient that the amount of smoke flavoring in the commercially available product used in the food of the present invention falls within the above range. The amount of smoke flavoring in the food can be measured by known analytical methods such as gas chromatography-mass spectrometry.

[0019] The food of the present invention may contain other components besides the aforementioned components (sodium acetate, organic acid, acetic acid, and smoke flavoring). These other components may be those known to be included in foods of the same type as the food of the present invention (for example, the prepared foods, seasonings, or wheat processed foods described later), and one of these may be used alone or in combination of two or more.

[0020] The pH of the food of the present invention at a temperature of 25°C is 5.0 to 7.0, preferably 5.0 to 6.3, and more preferably 5.2 to 6.1. By having the pH of a food containing a bacteriostatic agent (such as sodium acetate) within the specified range, undesirable sour taste and odor caused by the bacteriostatic agent are suppressed, and the desirable taste inherent in the food can be maintained. The pH of the food can be adjusted by adjusting the content of one or more of sodium acetate, organic acids, acetic acid, and smoke flavoring in the food. Basically, the pH of the food can be adjusted within the specified range by adjusting the content of sodium acetate, organic acids, acetic acid, and smoke flavoring in the food to within the specified range.

[0021] The pH of food can be measured by the following method. A suitable amount is sampled from the food to be measured to serve as the measurement sample. The amount of the measurement sample can be set arbitrarily. If the measurement sample is liquid or paste-like, a pH measuring device is used to measure the pH of the measurement sample at a temperature of 25°C. If the measurement sample is solid, 5 parts by mass of ion-exchanged water are added to 1 part by mass of the measurement sample, and the mixture is made into a paste using a stomacher or mixer. A pH measuring device is then used to measure the pH of the mixture at a temperature of 25°C. If the food to be measured is a dough-heated food as described later, the pH of the dough before heating can be used as the pH of the food. For example, a glass electrode type hydrogen ion concentration indicator manufactured by Toa DKK Co., Ltd. can be used as the pH measuring device.

[0022] Specific examples of the food products of the present invention include rice dishes, prepared foods, seasonings, and wheat processed foods.

[0023] In this specification, "rice products" refers to food products that primarily consist of rice. The aforementioned "rice products" refer to food products that have been cooked by adding water to grains of the grass family, such as rice. Specific examples of rice products include rice balls, rice burgers, red bean rice, sticky rice, cooked rice, packaged rice, sprouted brown rice, and dried rice products.

[0024] In this specification, "prepared foods" refers to foods that are eaten with staple foods, excluding rice dishes, seasonings, and wheat processed foods. Specific examples of "staple foods" include rice dishes, noodles, and bread. Staple foods are not included in prepared foods. Specific examples of prepared foods include boiled dishes, salads, grilled dishes, stir-fried dishes, deep-fried dishes, and steamed dishes.

[0025] In this specification, "seasonings" refers to food products used to flavor dishes, excluding prepared foods and wheat-based foods. Specific examples of seasonings include pasta sauces, gratin sauces, dipping sauces, and duxelles sauces.

[0026] In this specification, "wheat processed food" refers to food containing a portion obtained by processing wheat (hereinafter also referred to as the "wheat-derived portion"). Wheat processed food may consist entirely of the wheat-derived portion, or only a portion of it may consist of the wheat-derived portion. A specific example of a wheat processed food is a dough-heated food. In this specification, "dough-heated food" refers to food manufactured by using dough, which is a mixture of powdered raw materials such as wheat flour and liquid raw materials such as water, as an intermediate product, shaping the dough into a predetermined form, and then heating it, and includes a dough portion obtained by heating the dough. The dough portion is the wheat-derived portion. The term "dough" here includes clay-like dough (so-called dough) and liquid or paste-like dough (so-called batter). Specific examples of dough-heated foods include bakery foods, noodles, and breaded fried foods. Typically, bakery foods and noodles consist entirely of the wheat-derived portion, whereas in breaded fried foods, the breading is partly the wheat-derived portion, while other parts, such as the filling, may not be the wheat-derived portion.

[0027] In this specification, "bakery food" refers to food obtained by heating dough containing flour such as wheat flour and water (heated dough food). Bakery food also includes products that contain other ingredients (e.g., fillings) in addition to the heated dough. Bakery food is typically produced by heating dough prepared through a process of stirring powdered raw materials, including flour, in the presence of water. The dough may be fermented or unfermented. The method of heating the dough is not particularly limited, and is typically by baking, but an appropriate method can be selected from known heating methods depending on the type of bakery food, etc. Examples include heating using a cooking appliance such as a deep fryer or microwave oven. Specific examples of bakery food include bread, steamed buns, waffles, crepes, pancakes, hotcakes, sponge cakes, scones, okonomiyaki, takoyaki, obanyaki, and taiyaki.

[0028] In this specification, "noodles" refers to food products obtained by shaping dough containing wheat flour or other grain flours and water into predetermined shapes such as lines or sheets to obtain fresh noodles, and then cooking (for example, boiling) the fresh noodles or dried noodles thereof. Specific examples of noodles include udon, somen, hiyamugi, soba, Chinese noodles, and pasta. Noodles also include noodle wrappers, and specific examples of noodle wrappers include dumpling wrappers, spring roll wrappers, and bao.

[0029] In this specification, "breaded fried food" refers to food obtained by coating the surface of ingredients with a batter containing grain flour such as wheat flour and then cooking it in hot oil. In breaded fried food, the batter is usually a wheat-based food, while the ingredients are not. The types of ingredients are not particularly limited and include, for example, meats such as chicken, pork, beef, lamb, and goat; seafood such as squid, octopus, shrimp, horse mackerel, salmon, mackerel, and flounder; grains, vegetables, and root vegetables such as soybeans, rice, carrots, onions, potatoes, and sweet potatoes; and processed products of these. Specific examples of breaded fried food include tempura, tatsuta-age, fritters, tonkatsu, and corn dogs.

[0030] Wheat processed foods may be manufactured using flours other than wheat flour. In this specification, "flours" refers to substances derived from grains that are powdery at room temperature and pressure, and is a concept that includes flour and starch. Unless otherwise specified, "starch" here refers to "pure starch" isolated from plants such as wheat, and is distinguished from starch inherently present in flour. Examples of such flours include wheat flour (strong flour, semi-strong flour, medium flour, weak flour, durum wheat flour, whole wheat flour, etc.), buckwheat flour, rice flour, corn flour, barley flour, rye flour, adlay flour, barnyard millet flour, and foxtail millet flour. Flours may also be subjected to heat treatments such as dry heat treatment or moist heat treatment. Examples of the starches include unprocessed starches such as tapioca starch, potato starch, corn starch, waxy corn starch, wheat starch, and rice starch; and processed starches obtained by subjecting unprocessed starches to one or more treatments such as etherification, esterification, acetylation, dry heat treatment, moist heat treatment, crosslinking treatment, and oxidation treatment.

[0031] The food of the present invention can typically be produced by a known method for producing the same type of food. In the production of the food of the present invention, components to be included in the food (components according to the present invention), such as sodium acetate, organic acids, acetic acid, and smoke flavoring, can be used at any time during the production process of the food of the same type as the known food.

[0032] Furthermore, the food of the present invention may be a pre-cooked frozen food that can be eaten as is after natural thawing. Generally, when frozen foods are naturally thawed, there is a concern that microorganisms such as spore-forming bacteria remaining in the frozen food may proliferate during the period of being left at room temperature. However, the food of the present invention has the aforementioned features, thus eliminating such concerns. The aforementioned pre-cooked frozen food is obtained by freezing pre-cooked foods such as prepared foods and wheat processed foods. In this specification, "natural thawing" refers to thawing by leaving the frozen food in an environment where the ambient temperature is room temperature (for example, around 10 to 30°C) or a chilled temperature range (for example, around 10°C to the freezing start temperature), and is different from heating and thawing using a heating appliance such as a microwave oven. Therefore, the food of the present invention can be stored, distributed, and / or sold in a chilled temperature range. In other words, the food of the present invention is applicable to a distribution and sales method in which the food is frozen after manufacture, and the frozen food is kept at a chilled temperature range during distribution to maintain a low temperature, and then sold in that low temperature state. Such so-called frozen-chilled sales can effectively reduce the deterioration of quality associated with the storage and distribution of food.

[0033] Next, the food shelf-life extender of the present invention (hereinafter also simply referred to as "the food shelf-life extender of the present invention") will be described. The configuration of the food shelf-life extender of the present invention will be described in a manner that differs from that of the food of the present invention described above. For configurations of the food shelf-life extender of the present invention that are not specifically described above, the description of the food of the present invention described above will be applied as appropriate.

[0034] The shelf-life extender of the present invention includes a form containing sodium acetate and an organic acid (hereinafter also referred to as "first form") and a form containing acetic acid (hereinafter also referred to as "second form"). The essential components (bacteriostatic agents) are as described above. From the viewpoint of ensuring that the shelf life of food is improved without impairing the original flavor of the food, the content of these essential components in both forms is preferably adjusted as follows. The sodium acetate content in the first form of the shelf-life extender is 40 to 90% by mass of the total mass of the shelf-life extender, preferably 50 to 85% by mass, and more preferably 60 to 80% by mass. The organic acid content in the first form of the shelf-life extender is 1 to 15% by mass of the total mass of the shelf-life extender, preferably 2 to 10% by mass, and more preferably 3 to 8% by mass. The acetic acid content in the second form of the shelf-life extender is 3 to 15% by mass of the total mass of the shelf-life extender, preferably 5 to 13% by mass, and more preferably 7 to 11% by mass. In the first form, if the sodium acetate content is less than 40% by mass, or the organic acid content is 1% by mass, a sufficient bacteriostatic effect cannot be obtained, and the shelf life of the food cannot be improved. Also in the first form, if the sodium acetate content exceeds 90% by mass, or the organic acid content exceeds 15% by mass, an undesirable sour taste and odor caused by sodium acetate and / or organic acids becomes prominent, and the original flavor of the food may be impaired. In the second form, if the acetic acid content is less than 3% by mass, a sufficient bacteriostatic effect cannot be obtained, and the shelf life of the food cannot be improved. Also in the second form, if the acetic acid content exceeds 15% by mass, an undesirable sour taste and odor caused by acetic acid becomes prominent, and the original flavor of the food may be impaired.

[0035] The shelf-life extender of the present invention contains a smoke flavoring. The smoke flavoring is as described above. The smoke flavoring content in the shelf-life extender of the present invention is 0.25 to 5% by mass, preferably 1.6 to 4.5% by mass, and more preferably 3 to 4% by mass, based on the total mass of the shelf-life extender. If the smoke flavoring content is less than 0.25% by mass, there is a risk that the sour taste and odor caused by sodium acetate, organic acids, or acetic acid cannot be sufficiently suppressed. If the smoke flavoring content exceeds 5% by mass, there is a risk that the characteristic flavor of the smoke flavoring in the food will become too strong, resulting in the food's original flavor being impaired. When using commercially available smoke flavoring, it is sufficient that the content of the commercially available smoke flavoring in the shelf-life extender of the present invention is within the above range.

[0036] The pH of a 1% by mass aqueous solution of the shelf-life extender of the present invention at a temperature of 25°C is 4.5 to 6.5, preferably 4.7 to 6.3, and more preferably 4.9 to 6.1. The aqueous solution is a mixture of the shelf-life extender and water, wherein the shelf-life extender is present in a liquid containing 1% by mass of the total mass of the aqueous solution. By having the pH of the aqueous solution within the specified range, undesirable sour taste and odor caused by bacteriostatic agents such as sodium acetate contained in the shelf-life extender are suppressed, and the desirable taste inherent in the food can be maintained. In the first embodiment, the pH of the aqueous solution can be adjusted by adjusting the content of sodium acetate and one or more organic acids, and in the second embodiment, it can be adjusted by adjusting the content of acetic acid. Basically, in the first or second embodiment, the pH of the aqueous solution can be adjusted within the specified range by adjusting the content of these components within the specified range.

[0037] The shelf-life extender of the present invention may contain other components besides the essential components (sodium acetate and organic acid in the first form, acetic acid in the second form, and smoke flavoring as an essential component common to both forms), provided that the predetermined effects of the present invention are not inhibited. Specific examples of the other components used to enhance the shelf-life extender effect include glycine, lysozyme, emulsifiers, and chelating agents. Specific examples of the other components used to stabilize the formulation include dextrin, sucrose fatty acid esters, calcium stearate, and glycerin fatty acid esters. In the present invention, one of the other components may be used alone or in combination of two or more.

[0038] The shelf-life extender of the present invention can be manufactured by mixing the above-mentioned components. The shelf-life extender of the present invention is typically a powder or granular substance or a liquid or paste that is fluid at room temperature and atmospheric pressure. In this specification, "room temperature and atmospheric pressure" refers to the ambient temperature and atmospheric pressure of the environment in which the food or shelf-life extender of the present invention is normally manufactured and used (e.g., consumed), and is typically an environment with an ambient temperature of 25°C and an atmospheric pressure of 1 atmosphere.

[0039] The shelf-life extender of the present invention can be used in food in the same way as shelf-life extenders of this type. Methods of using the shelf-life extender of the present invention include adding it to an intermediate product of the food during the food manufacturing process, spraying or coating it onto the finished food product, or immersing the finished food product in the shelf-life extender. When applying the shelf-life extender of the present invention to food, it may also be used in the form of the shelf-life extender dissolved or dispersed in a suitable solvent (e.g., water).

[0040] The food shelf-life extender of the present invention is not particularly limited in terms of the types of foods it can be used in, and can be used in both heat-treated and unheat-treated foods. Specific examples of foods to which the food shelf-life extender of the present invention can be used include prepared foods, seasonings, and wheat-based processed foods.

[0041] The amount of the shelf-life improving agent of the present invention used for food is preferably adjusted such that the content of each component (sodium acetate and an organic acid in the first embodiment, acetic acid in the second embodiment, and smoke liquid as an essential component common to both embodiments) in the shelf-life improving agent in the food to which the shelf-life improving agent is added falls within the same range as that described above for the food of the present invention.

[0042] The present invention includes a method for inhibiting perception of sour taste and acid odor in food containing sodium acetate or an organic acid. The method for inhibiting perception of sour taste and acid odor of the present invention is described below. For the method for inhibiting perception of sour taste and acid odor of the present invention, configurations different from those of the food and the shelf-life improving agent of the present invention described above will be explained. For configurations not particularly described in the method for inhibiting perception of sour taste and acid odor of the present invention, the above descriptions regarding the food or the shelf-life improving agent of the present invention are applied as appropriate.

[0043] The method for inhibiting perception of sour taste and acid odor of the present invention comprises adding smoke liquid to food containing sodium acetate or an organic acid (hereinafter also referred to as "bacteriostatic agent-containing food"). This makes it possible to reduce undesirable sour taste and acid odor caused by sodium acetate or an organic acid, and improve the storage stability of food through the bacteriostatic effect of sodium acetate or an organic acid while maintaining the inherent flavor of food not containing sodium acetate and an organic acid. The effect of smoke liquid in reducing sour taste and acid odor caused by sodium acetate or an organic acid is mainly achieved by so-called masking, which conceals the sour taste and acid odor with the flavor of the smoke liquid.

[0044] In the method for inhibiting perception of sour taste and acid odor of the present invention, the amount of smoke liquid used for the bacteriostatic agent-containing food is preferably adjusted such that the content of the smoke liquid in the bacteriostatic agent-containing food to which the smoke liquid is added falls within the same range as that described above for the food of the present invention.

[0045] The bacteriostatic agent-containing food to which the method for inhibiting perception of sour taste and acid odor of the present invention can be applied is not particularly limited, and the method can be used for both heat-treated food and non-heat-treated food. Specific examples of bacteriostatic agent-containing food to which the method for inhibiting perception of sour taste and acid odor of the present invention can be applied include prepared dishes, seasonings, and processed wheat foods.

[0046] Hereinafter, the present invention will be described in more detail by way of Examples, but the present invention is not limited to the following Examples.

[0047] [Preparation of shelf-life improver] Various raw materials shown in Table 1 below were mixed, and powdery and granular shelf-life improvers a to d were produced at normal temperature and normal pressure. Details of the raw materials used are as follows. ・Smoke liquid A: trade name "SmokEz LFBN" (manufacturer: Kerry (USA), distributor: Wisco International Co., Ltd.), pH 5.7 at a product temperature of 25°C ・Smoke liquid B: trade name "SmokEz H-10" (manufacturer: Kerry (USA), distributor: Wisco International Co., Ltd.), pH 2.6 at a product temperature of 25°C

[0048]

[0049] [Examples and Comparative Examples: Production of foods containing shelf-life improver] Spinach ohitashi, a type of prepared side dish (simmered dish or seasoned salad), carbonara sauce, a type of seasoning (pasta sauce), and pancake, a type of processed wheat food (bakery product), were produced. Any one of the shelf-life improvers a to d was added to these three types of foods to produce foods containing the shelf-life improver. Examples A1 to A3 and Comparative Examples A1 to A3 produced spinach ohitashi containing the shelf-life improver, Examples B1 to B3 and Comparative Examples B1 to B3 produced carbonara sauce containing the shelf-life improver, and Examples C1 to C3 and Comparative Examples C1 to C3 produced pancakes containing the shelf-life improver. Specific production methods for each food are as follows. The blending amounts of raw materials and food compositions during the production of each food are shown in Tables 2 to 4 below.

[0050] (Method for making blanched spinach) 300g of soy sauce (Kikkoman Koikuchi Soy Sauce, manufactured by Kikkoman Corporation), 100g of refined sugar (DM Mitsui Sugar Co., Ltd. "Refined Sugar"), 250g of mirin (Takara Hon Mirin, manufactured by Takara Shuzo Co., Ltd.), 5g of kelp stock (Hondashi Kombu Dashi, manufactured by Ajinomoto Co., Inc.), 5g of bonito stock (Hondashi Katsuo Dashi, manufactured by Ajinomoto Co., Inc.), and 340g of water were measured into a pot and heated to 85°C. Heating was stopped after reaching the desired temperature. After cooling, water was added to compensate for evaporation during heating, bringing the total to 1000g to make the dressing. Frozen spinach was placed in boiling water and boiled. After boiling again, the spinach was removed 2 minutes later and cooled under running water for 1 minute. The water was drained to a yield of about 75%, and this was used as boiled spinach. A shelf-life extender was added to the aforementioned dressing broth to obtain a dressing broth containing a shelf-life extender. This broth was then added in a quantity of 1 part by mass to 10 parts by mass of the boiled spinach and mixed well. Water was added as needed to equalize the total weight in each production example, and the spinach salad with shelf-life extender was prepared.

[0051] (Method for manufacturing carbonara sauce) A shelf-life extender was added to commercially available carbonara sauce ("Ma-Ma Milk-Rich Carbonara Sauce" manufactured by Nisshin Flour Milling Co., Ltd. Welna Co., Ltd.) and mixed. Water was added as needed to equalize the total weight in each manufacturing example, and carbonara sauce with a shelf-life extender was produced.

[0052] (Method for making pancakes) One egg and 140 ml of water were placed in a bowl and mixed well with a whisk. 200 g of commercially available pancake mix (Nisshin Hotcake Mix with Zipper, manufactured by Nisshin Flour Milling Co., Ltd.) and a shelf-life extender were added and mixed well with a whisk. Water was added as needed to equalize the total weight in each production example, and the mixture was thoroughly mixed to make the pancake batter. The batter was poured into a heated frying pan and heated over low heat for about 3 minutes. The pancakes were then flipped over and heated over low heat for about 2 minutes to produce pancakes with a shelf-life extender.

[0053] [Evaluation Test 1] The bacteriostatic properties of the foods containing shelf-life extenders produced in the examples and comparative examples were evaluated. Specifically, a method corresponding to the type of food being evaluated was selected from the various food evaluation methods listed below, and the bacteriostatic properties were evaluated according to the selected evaluation method. Bacteriostatic properties were evaluated using the number of growing bacteria as an indicator. A value of A (highest evaluation) was assigned when the maximum number of growing bacteria was less than 2.0 LOGcfu / g, B was assigned when the maximum value was 2.0 LOGcfu / g or more but less than 3.0 LOGcfu / g, and C was assigned when the maximum value was 3.0 LOGcfu / g or more. The results are shown in Tables 2 to 4 below.

[0054] (Method for evaluating the bacteriostatic properties of blanched spinach) Blanched spinach to be evaluated was inoculated with approximately 50 cfu / g of the lactic acid bacterium Leuconostoc mesenteroides, and then left to stand for 72 hours in an environment with an ambient temperature of 10°C. The blanched spinach after inoculation with lactic acid bacteria was diluted 10-fold with peptone water to obtain a sample solution, and this sample solution was diluted as appropriate and spread on a standard agar plate to measure the number of viable cells. The number of viable cells was measured by the surface smear method. Specifically, it was as follows: 0.1 mL of the sample solution or 0.1 mL of a diluted sample solution obtained by diluting the sample solution 10-fold or 100-fold was dropped onto the surface of a pre-solidified agar plate, spread evenly with a Conlarger rod, and cultured. Aerobic culture at 30°C for 48 hours using a standard agar plate was adopted as the culture medium and culture conditions. The number of viable cells was measured by multiplying the number of colonies grown in the culture medium by the dilution factor to obtain the number of viable cells per gram of culture medium (LOGcfu / g). The number of cells was converted to a logarithm, and the initial number of cells was subtracted to calculate the number of cells that had grown.

[0055] (Method for evaluating the bacteriostatic properties of carbonara sauce) Approximately 200 cfu / g of Bacillus cereus spores were inoculated into the carbonara sauce to be evaluated, and it was left to stand for 24 hours in an environment with an ambient temperature of 30°C. The carbonara sauce after inoculation with Bacillus cereus was diluted 10-fold with peptone water to obtain a sample solution, and this sample solution was diluted as appropriate and spread on a standard agar plate to measure the number of viable cells. The number of viable cells was measured by the surface smear method. Specifically, it was as follows: 0.1 mL of the sample solution or 0.1 mL of a diluted sample solution obtained by diluting the sample solution 10-fold or 100-fold was dropped onto the surface of a pre-solidified agar plate, spread evenly with a Conlarger rod, and cultured. Aerobic culture at 35°C for 24 hours using a standard agar plate was adopted as the culture medium and culture conditions. The number of viable cells was measured by multiplying the number of colonies grown in the culture medium by the dilution factor to obtain the number of viable cells per gram of culture medium (LOGcfu / g). The number of cells was converted to a logarithm, and the initial number of cells was subtracted to calculate the number of cells that had grown.

[0056] (Method for evaluating the bacteriostatic properties of pancakes) Approximately 200 cfu / g of Bacillus cereus spores were inoculated into the pancakes to be evaluated, and then left to stand for 9 hours in an environment with an ambient temperature of 30°C. The pancakes inoculated with Bacillus cereus were diluted 10-fold with peptone water to obtain a sample solution, and this sample solution was diluted as appropriate and spread onto standard agar plates to measure the number of viable cells. The number of viable cells was measured by the surface smear method. Specifically, it was as follows: 0.1 mL of the sample solution or 0.1 mL of a diluted sample solution obtained by diluting the sample solution 10-fold or 100-fold was dropped onto the surface of agar plates that had been pre-solidified, and the mixture was spread evenly with a convection wand and cultured. Aerobic culture at 35°C for 24 hours using standard agar medium was adopted as the culture medium and culture conditions. The number of viable cells was measured by multiplying the number of colonies grown in the culture medium by the dilution factor to obtain the number of viable cells per gram of culture medium (LOGcfu / g).

[0057] [Evaluation Test 2] The flavor of the foods containing shelf-life extenders produced in the examples and comparative examples was evaluated. Specifically, five expert panelists tasted the foods to be evaluated and evaluated them according to the following criteria. The arithmetic mean of the evaluation scores from the five panelists was used as the evaluation result for the food. The results are shown in Tables 2 to 4 below.

[0058] <Flavor Evaluation Criteria> 5 points: No sourness or sour odor detected, extremely good. 4 points: Slight sourness or sour odor detected, good. 3 points: Sourness or sour odor detected, but within acceptable limits. 2 points: Strong sourness or sour odor detected, poor. 1 point: Very strong sourness or sour odor detected, extremely poor.

[0059]

[0060]

[0061]

[0062] As shown in Tables 2 to 4, the foods in each example contained 0.2 to 2% by mass of sodium acetate and 0.01 to 0.2% by mass of organic acid (citric acid), and the smoke flavoring content was 0.005 to 0.5% by mass. Therefore, compared to the comparative examples that did not meet these criteria, they all received high ratings in terms of bacteriostatic properties, flavor, and appearance. Furthermore, in the comparison between Example A1 and Example A3 in Table 2, between Example B1 and Example B3 in Table 3, and between Example C1 and Example C3 in Table 4, the examples containing smoke flavoring A with a pH of 5.7 received higher flavor ratings and less sour taste and odor compared to the examples containing smoke flavoring B with a pH of 2.6. This indicates that including smoke flavoring with a pH of around 5.7 in the food is an effective method for inhibiting the perception of sour taste and odor in foods containing sodium acetate and organic acid. Industrial applicability

[0063] The food of the present invention has excellent preservation properties because it contains a bacteriostatic component, and the original flavor of the food is less likely to be impaired by the component, resulting in a good flavor. Furthermore, the food preservation agent of the present invention can improve the preservation of food without impairing the original flavor of the food. In addition, the method for inhibiting the perception of sour taste and sour odor of the present invention makes it difficult to perceive the sour taste and sour odor caused by organic acids (sodium acetate or organic acids) that exhibit bacteriostatic effects in food, thus maintaining the original flavor of the food.

Claims

1. A food product containing 0.2 to 2% by mass of sodium acetate and 0.01 to 0.2% by mass of an organic acid, or 0.02 to 0.2% by mass of acetic acid, and 0.005 to 0.5% by mass of smoke flavoring, with a pH of 5.0 to 7.0 at a product temperature of 25°C.

2. The food according to claim 1, wherein the organic acid comprises at least one selected from the group consisting of acetic acid, citric acid, malic acid, fumaric acid, adipic acid, glucono delta-lactone, gluconic acid, succinic acid, tartaric acid, ascorbic acid, and lactic acid.

3. The food according to claim 1 or 2, wherein the pH of the smoke solution at a product temperature of 25°C is 4.5 to 6.

5.

4. The food according to claim 1 or 2, which is rice, prepared food, seasoning, or wheat processed food.

5. A food preservative containing 40-90% by mass of sodium acetate, 1-15% by mass of an organic acid, or 3-15% by mass of acetic acid, and 0.25-5% by mass of smoke flavoring, wherein the pH of a 1% by mass aqueous solution at a product temperature of 25°C is 4.5-6.

5.

6. The food shelf-life extender according to claim 5, wherein the organic acid comprises at least one selected from the group consisting of acetic acid, citric acid, malic acid, fumaric acid, adipic acid, glucono delta-lactone, gluconic acid, succinic acid, tartaric acid, ascorbic acid, and lactic acid.

7. A method for inhibiting the perception of sour taste and sour odor in a food containing sodium acetate or an organic acid, comprising adding smoke flavoring to the food.

Images