Coating agent for food, food, and packaging material for food

Abstract

To provide a coating agent for food which, when directly applied to the food, causes no taste change in eating the food and which can lengthen a use-by date and a best-before date.SOLUTION: There are provided: a coating agent for food contains shellac, tannic acid, and ethanol; a food with the coating agent for food; a packaging material for food; and a best-before date lengthening method. The mass ratio of the shellac to the tannic acid is preferably shellac:tannic=100:1 to 100:100.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a food coating agent that can be directly coated on food.

Background Art

[0002] One of the Sustainable Development Goals (SDGs) that the world should strive for by 2030 is to reduce food loss. In 2019, the Food Loss Reduction Promotion Act was implemented, and as one of the efforts to reduce food loss, extending the expiration date and the best-before date from various perspectives has been under consideration.

[0003] Since Japan is a region with high temperature and high humidity, measures against mold contamination and spoilage have been conventionally taken. In particular, for fresh fruits and vegetables such as citrus fruits, which are prone to mold growth, methods of coating the surface of citrus fruits with capillin and polyphenols (see, for example, Patent Documents 1 and 2) and methods of coating the surface of citrus fruits with a composition containing tannin (see, for example, Patent Document 3) have been studied. However, the methods described in Patent Documents 1 to 3 are for citrus fruits having an outer peel, which is a substantially non-edible part of the target food, and the coating agent is assumed to be coated on the outer peel. Therefore, no consideration has been given to the deterioration of the taste of the coated food.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] The problem to be solved by the present invention is to provide a food coating agent that does not cause a change in taste even when eaten in a state directly coated on food and can extend the expiration date or the best-before date.

Means for Solving the Problem

[0006] That is, the present invention provides a food coating agent containing shellac, tannic acid, and ethanol.

[0007] The present invention also provides a food coated with the above-described food coating agent.

[0008] The present invention also provides a food packaging material coated with the above-described food coating agent.

[0009] The present invention also provides a method for extending the best-before date by coating the above-described food coating agent on food.

Mode for Carrying Out the Invention

[0010] The food coating agent of the present invention contains shellac, tannic acid, and ethanol.

[0011] (Shellac) The shellac used in the present invention is a resin obtained by purifying the resinous insect coatings secreted by a kind of scale insect, lac scale insect, and several related scale insects by known solution extraction methods, soda methods, etc. (also referred to as shellac resin). Its components are composed of a mixture of a large number of resin acids for film formation and their esterified products, waxes, and pigments. The resin acids are aleuritic acid, jararic acid, and laccijaraic acid, and are natural shellac resins or synthetic shellac resins mainly composed of ester compounds with these resin acids. Examples include purified shellac resin, bleached shellac resin, decolorized shellac resin, etc.

[0012] The refined shellac resin is obtained by removing impurities from the resinous substance secreted by the lac bug through filtration. The bleached shellac resin (white shellac) is obtained by dissolving the resinous substance in an aqueous alkali solution, bleaching it with sodium hypochlorite, and neutralizing and precipitating the alkali with an inorganic acid. The decolorized shellac resin is obtained by physically removing pigments for decolorization. Among these shellacs, decolorized shellac or refined shellac is particularly preferred. Note that the shellac resin used in the present invention is not particularly limited by the production area, type of raw material, purification method, etc.

[0013] In the present invention, the shellac resin serves as a base of the coating agent, and the coating formed by the coating agent can coat the object to be coated and impart functions such as a moisture-proof function, an antioxidant function, a gloss function, a masking function, and a stabilizing function. The shellac resin preferably contains 50% by mass to 99% by mass, more preferably 80% by mass to 95% by mass, based on the total solid content of the food coating agent of the present invention.

[0014] (Tannic acid) The tannic acid used in the present invention is a polyphenol compound having a structure in which a plurality of gallic acid molecules are bonded to glucose. Tannic acid can be easily obtained from plants, for example. The origin and form of the tannic acid used in the present invention are not particularly limited, and for example, partially purified tannic acid such as a plant extract, tannic acid isolated from a plant, artificially synthesized tannic acid, etc. can be used, and they may be used in combination.

[0015] In the present invention, tannic acid is added for the purpose of having an antiseptic effect and a mold-proof effect on food. From that viewpoint, it preferably contains 1% by mass to 50% by mass, more preferably 5% by mass to 20% by mass, based on the total solid content of the food coating agent of the present invention.

[0016] On the other hand, since tannic acid has an astringent effect, it has a bitter and astringent taste when eaten. The content within the above range that exhibits the antiseptic effect and anti-mold effect on food sometimes gives the taste of the applied food a bitter and astringent taste, leading to the deterioration of the taste of the applied food. In the present invention, it is preferable that the mass ratio of shellac to tannic acid is shellac:tannic acid = 100:1 to 100:100. In this range, even when eaten in a state directly coated on food, the taste derived from tannic acid does not change, and the antiseptic effect and anti-mold effect of tannic acid, together with the moisture-proof function, antioxidant function, gloss function, masking function, stabilization function, etc. due to shellac coating, are integrated, making it possible to extend the expiration date and the best-before date. Among them, it is still more preferable that shellac:tannic acid = 100:1 to 100:100, and more preferably shellac:tannic acid = 100:5 to 100:20.

[0017] (Ethanol) In the present invention, it is preferable to use alcohol as a solvent for quickly volatilizing after dissolving shellac and tannic acid and coating the surface of the object to be coated with the coating agent composition. The type of alcohol is appropriately selected from ethanol, isopropanol, or hydrous alcohol according to the application, but ethanol is preferable when the object to be coated is food. Two or more kinds of the above alcohols may be selected and used in combination.

[0018] As the hydrous alcohol, ethanol or isopropanol with a water content of 30% by volume or less is preferable. When the water content exceeds 30% by volume, shellac precipitates, and when the water content is even higher, the drying property during coating deteriorates, and the working time becomes long, which is not preferable.

[0019] (Other components) In the present invention, other additives such as polysaccharides, lipids, and proteins can also be contained within a range that does not impair the effects of the present invention.

[0020] Examples of polysaccharides that can be used in the present invention include hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), methyl cellulose (MC), starch and derivatives (e.g., native starch, modified starch, gelatinized starch, dextrin, maltodextrin, corn syrup, sucrose, dextrose / fructose, and sugar polyols); exudate gums (e.g., gum arabic, gutta-percha, karaya gum, and tragacanth gum); seed gums (e.g., guar gum and locust bean gum); microbial fermentation gums (e.g., xanthan, gallan gum, and chilosan); seaweed extracts (e.g., agar, alginate, carrageenan, and furcelleran); and pectin.

[0021] Examples of lipids that can be used in the present invention include waxes and oils (e.g., paraffin wax, carnauba wax, beeswax, candelilla wax, and polyethylene wax); fatty acids and monoglycerides (e.g., stearyl alcohol, stearic acid, palmitic acid, monoglyceride, and diglyceride); naturally occurring resins (e.g., wood resin); and coumarone-indene, vegetable oil, mineral oil, medium-chain triglyceride, fat, essential oils (e.g., thymol, lemongrass, cumin, cinnamon).

[0022] Examples of proteins that can be used in the present invention include corn zein (α-zein, β-zein, and / or γ-zein), wheat gluten, soybean protein, peanut protein, keratin, collagen, gelatin, milk protein (casein), and whey protein, gluten, glycerin, silk protein.

[0023] (Food) By coating the food coating agent of the present invention on food, food with an extended expiration date or shelf life can be obtained. In the present invention, "food" refers to substances for animal consumption (including feed, forage, etc.), and typically refers to substances for human consumption. Examples of food include fresh produce (such as vegetables, fruits, wild vegetables, mushrooms, etc.), seafood, etc., which are collectively also referred to as fresh food. Here, vegetables include leafy vegetables, root vegetables, and fruit vegetables according to the part used. Fruit means the fruit for human consumption. Wild vegetables mean plants growing wild in the mountains and used for human consumption. Mushrooms mean organisms classified as fungi that form fruiting bodies visible to the naked eye or the fruiting bodies themselves and are used for human consumption. Seafood means aquatic animals such as fish and shellfish for human consumption.

[0024] Also, as food, processed foods obtained by using the above-mentioned fresh produce, seafood, etc. as raw materials and subjecting the raw materials to some processing may be used. For example, foods that have been cooked by boiling, steaming, boiling, roasting, frying, etc. (such as boiled shrimp, grilled fish, etc.) before being delivered to consumers as products, or foods prepared using various materials (such as dumplings, shumai, kamaboko, fish cakes, etc.) may be mentioned.

[0025] In addition, the foods to which the food coating agent of the present invention can be applied can also be classified according to the amount of nutrients contained in the food. Specifically, foods rich in carbohydrates (sugars) (such as cooked rice, mochi, noodles, bread, steamed buns, etc., also called staple foods), foods rich in protein (such as seafood, eggs, soybeans, processed soy foods, etc., also called main dishes), and foods rich in vitamins, minerals, and dietary fiber (such as vegetables, mushrooms, seaweeds, etc., also called side dishes) may be mentioned.

[0026] In this specification, the "coating" of food refers to a state in which a thin film of the food coating agent of the present invention is formed on at least a part or the whole of the surface of the food. In the present invention, if a thin film of the food coating agent of the present invention is formed on at least a part of the surface of the food, the effects of the present invention can be obtained. Therefore, it is not necessary for the polymer thin film to be formed on the whole surface of the food. Depending on the size of the food to be coated (hereinafter, also simply referred to as "target food"), the size (surface area), shape (such as unevenness), properties (such as wettability), etc. of the surface to which the aqueous solution or alcohol aqueous solution of the raw material compound described later is to be applied, or depending on the conditions required for maintaining the freshness of the target food, etc., the location and range of coating can be set. On the other hand, for example, in order to maximize the effects of the present invention on fresh foods, etc., it is preferably in a state of covering 50% or more of the surface area of the food, more preferably in a state of covering 90% or more, and most preferably in a state of covering 100%.

[0027] The method for coating the food coating agent of the present invention on the surface of food is not particularly limited and can be appropriately selected. Specifically, methods such as spraying, coating methods using brushes or brushes, methods using known coating devices such as spin coating devices, and methods of immersing a part or the whole of the surface of the food in the food coating agent for a certain period of time can be mentioned.

[0028] The film thickness when coating the food coating agent of the present invention on the surface of food is not particularly limited, but is preferably 1 to 50 μm, and more preferably 3 to 15 μm.

[0029] (Food packaging material) By coating the food coating agent of the present invention on materials for food packaging, such as films, etc., it becomes possible to extend the expiration date and the best-before date of the packaged food. The food coating agent of the present invention is preferably coated on the inside of the packaging material using the film or laminate for food packaging described later, that is, the side in contact with the food.

[0030] (Film) The film used as the material for food packaging is not particularly limited, and examples include polyethylene terephthalate (PET) film, polystyrene film, polyamide film, polyacrylonitrile film, polyethylene film (OPE: biaxially oriented polyethylene film, LLDPE: low-density polyethylene film, HDPE: high-density polyethylene film), polyolefin films such as polypropylene film (CPP: unoriented polypropylene film, OPP: biaxially oriented polypropylene film), polyvinyl alcohol film, ethylene-vinyl alcohol copolymer film, cellophane, etc.

[0031] In addition, films with an inorganic vapor deposition layer such as a metal like aluminum or a metal oxide like silica or alumina laminated on these films can also be used. Specific examples include OPP film, PET film, LLDPE film, CPP film having an aluminum vapor deposition layer, OPP film, PET film, nylon film having a silica vapor deposition layer, OPP film, PET film, nylon film having an alumina vapor deposition layer, etc. The coating agent of the present invention has excellent adhesion to these base materials including polyolefin films and can improve the gas barrier properties of the base materials and the fragrance retention properties of various fragrance components.

[0032] When considering a single-material package, a film made of a thermoplastic resin mainly composed of an olefin-based resin can be used as the base material. Specific examples of the olefin-based resin include polyethylene such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear (linear) low-density polyethylene, polypropylene, ethylene-propylene copolymer, α-olefin polymer, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-acrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl acrylate copolymer, cyclic olefin resin, ionomer resin, polyolefin resins such as polymethylpentene; and modified olefin-based resins obtained by modifying olefin resins with acrylic acid, methacrylic acid, maleic anhydride, fumaric acid, and other unsaturated carboxylic acids.

[0033] Also, it is also preferable to use a film formed of a material containing a biomass-derived component as the film substrate. Biomass films are sold by various companies, and for example, a sheet such as those listed in the list of biomass-certified products described by the Japan Organic Resources Association, Inc. can be used.

[0034] Specifically, a well-known film is made from ethylene glycol derived from biomass. Ethylene glycol derived from biomass is made from ethanol (biomass ethanol) produced from biomass as a raw material. For example, biomass-derived ethylene glycol can be obtained by a method of producing ethylene glycol via ethylene oxide from biomass ethanol by a conventionally known method or the like. Also, commercially available biomass ethylene glycol may be used, and for example, biomass ethylene glycol commercially available from Indiaglycol Co., Ltd. can be preferably used.

[0035] Alternatively, products using biomass raw materials distinguished by the biomass plastic content defined in ISO 16620 or ASTM D6866 are also on the market. Radiocarbon 14C exists in the atmosphere at a ratio of 1 in 1012, and this ratio remains the same even in atmospheric carbon dioxide. Therefore, this ratio also remains unchanged in plants that have fixed this carbon dioxide through photosynthesis. For this reason, the carbon in plant-derived resins contains radiocarbon 14C. In contrast, the carbon in fossil fuel-derived resins contains almost no radiocarbon 14C. Therefore, by measuring the concentration of radiocarbon 14C in the resin using an accelerator mass spectrometer, it is possible to determine the content ratio of plant-derived resins in the resin, that is, the biomass plastic content. Examples of plant-derived low-density polyethylene that is a biomass plastic with a biomass plastic content of 80% or more, preferably 90% or more, as defined in ISO 16620 or ASTM D6866 include products named "SBC818", "SPB608", "SBF0323HC", "STN7006", "SEB853", "SPB681", etc. manufactured by Braskem. Films using these as raw materials can be preferably used.

[0036] For example, as an alternative to conventional polyolefin films using petroleum-based raw materials, biomass polyolefin films such as biomass polyethylene films containing a polyethylene resin made from ethylene glycol derived from biomass and biomass polyethylene - polypropylene films are also known. The polyethylene resin is not particularly limited except that a part of the raw material uses the ethylene glycol derived from the biomass. Examples include homopolymers of ethylene and copolymers of ethylene and α-olefins with ethylene as the main component (ethylene-α-olefin copolymers containing 90% by mass or more of ethylene units). These can be used alone or in combination of two or more. The α-olefin constituting the copolymer of ethylene and α-olefin is not particularly limited, and examples thereof include α-olefins having 4 to 8 carbon atoms such as 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-octene. Known polyethylene resins such as low-density polyethylene resin, medium-density polyethylene resin, and linear low-density polyethylene resin can be used. Among them, from the viewpoint of making it less likely to cause damage such as perforation or tearing even when the films rub against each other, linear low-density polyethylene resin (LLDPE) (a copolymer of ethylene and 1-hexene, or a copolymer of ethylene and 1-octene) is preferable, and a linear low-density polyethylene resin having a density of 0.910 to 0.925 g / cm3 is more preferable.

[0037] The biomass film may be a laminate in which a plurality of biomass films are laminated, or may be a laminate of a conventional petroleum-based film and a biomass film.

[0038] The film may be subjected to some surface treatment, such as physical treatment such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, flame treatment, etc., or chemical treatment such as oxidation treatment using chemicals, or other treatments.

[0039] The base material can be produced by a conventionally known film-forming method such as an extrusion method, a casting method, a T-die method, a cutting method, an inflation method, etc. using the above-described resin. It may be an unstretched film, or may be stretched in one or two directions using a tenter method, a tubular method, etc. from the viewpoints of the strength, dimensional stability, and heat resistance of the film (1).

[0040] The base material may contain additives as required. Specifically, for the purpose of improving or modifying processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, lubricity, mold release properties, flame retardancy, antifungal properties, electrical properties, strength, etc., plastic compounding agents and additives such as elastomers, lubricants, crosslinking agents, antioxidants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, etc. can be added. The addition amount of the additive is adjusted within a range that does not affect other performances and recyclability.

[0041] The film thickness of the base material is not particularly limited, and it may be appropriately selected within the range of 0.1 to 300 μm from the viewpoints of moldability and transparency. Preferably, it is in the range of 0.3 to 100 μm. If it is less than 0.1 μm, the strength is insufficient, and if it exceeds 300 μm, the rigidity becomes too high and processing may become difficult.

[0042] From the viewpoint of recycling, it is preferably as simple as possible in layer structure. However, from the viewpoint of the flowability of the packaging material, printing for displaying the contents, description, and name of the product of the packaging material is often necessary. The base material is often printed as well. For this purpose, liquid inks such as gravure printing ink and flexographic printing ink are often used as the printing ink.

[0043] (Printing layer) The printing layer is a layer in which characters, figures, symbols, and other desired patterns are printed using a liquid ink or the like. The position where the laminate is provided is arbitrary. In this specification, the liquid ink is a general term for solvent-based inks used for gravure printing or flexographic printing. It may contain resin, colorant, and solvent as essential components, or it may be a so-called clear ink that contains resin and solvent and substantially does not contain a colorant.

[0044] The resin used in the liquid ink is not particularly limited. For example, acrylic resin, polyester resin, styrene resin, styrene-maleic acid resin, maleic acid resin, polyamide resin, polyurethane resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-acrylic copolymer resin, ethylene-vinyl acetate copolymer resin, vinyl acetate resin, polyvinyl chloride resin, chlorinated polypropylene resin, cellulose-based resin, epoxy resin, alkyd resin, rosin-based resin, rosin-modified maleic acid resin, ketone resin, cyclized rubber, chlorinated rubber, butyral, petroleum resin, etc. can be mentioned, and one or more of them can be used in combination. Preferably, it is at least one selected from polyurethane resin, vinyl chloride-vinyl acetate copolymer resin, and cellulose-based resin, or two or more of them.

[0045] Examples of the colorant used in the liquid ink include inorganic pigments such as titanium oxide, red lead, antimony red, cadmium red, cadmium yellow, cobalt blue, ultramarine blue, ultramarine, carbon black, and graphite, soluble azo pigments, insoluble azo pigments, azo lake pigments, condensed azo pigments, copper phthalocyanine pigments, organic pigments such as condensed polycyclic pigments, and extender pigments such as calcium carbonate, kaolin clay, barium sulfate, aluminum hydroxide, and talc.

[0046] The organic solvent used in the liquid ink preferably does not contain aromatic hydrocarbon-based organic solvents. More specifically, alcohol-based organic solvents such as methanol, ethanol, n-propanol, isopropanol, and butanol, ketone-based organic solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, ester-based organic solvents such as methyl acetate, ethyl acetate, propyl acetate, and butyl acetate, aliphatic hydrocarbon-based organic solvents such as n-hexane, n-heptane, and n-octane, and alicyclic hydrocarbon-based organic solvents such as cyclohexane, methylcyclohexane, ethylcyclohexane, cycloheptane, and cyclooctane can be mentioned, and one or more of them can be used in combination.

[0047] (Adhesive) A laminate in which a plurality of films or the like are laminated is also often used. The laminate has a structure in which a plurality of layers of films or the like are laminated by an adhesive or an extrusion method. As the adhesive, for example, a two-component curable urethane-based solvent type or solvent-free adhesive usually used for film adhesion can be used.

[0048] The method of applying the food coating agent of the present invention to the film or laminate for food packaging is not particularly limited, and a spray method, a spin coating method, a dip method, a roll coating method, a blade coating method, a doctor roll method, a doctor blade method, a curtain coating method, a slit coating method, a screen printing method, an inkjet method, a dispensing method, a die coating (die coating) method, a direct gravure method, a reverse gravure method, a flexo method, a knife coating method, a dot coating method, etc. can be used.

[0049] The film thickness of the food coating agent can be appropriately adjusted according to the type of the base material and the like, but as an example, it is preferably 3 μm or more and 15 μm or less.

Examples

[0050] Hereinafter, the present invention will be specifically shown by examples, but the present invention is not limited thereto. In the following examples, "g", "parts", "%", etc. represent "mass g", "mass parts", and "mass %" respectively unless otherwise specified.

[0051] Compositions of Examples 1 to 3 and Comparative Examples 2 to 4 were prepared and tested based on Test Examples 1 to 4. Details of Examples 1 to 3, Comparative Examples 1 to 4, and Test Examples 1 to 4 are as follows.

[0052] (Example 1) 25 g of decolorized shellac PEARL-N811 (manufactured by Gifu Shellac Co., Ltd.), 2.5 g of tannic acid ("G tannic acid" manufactured by Gokyo Food & Chemical Co., Ltd.), and 75 g of ethanol were mixed to prepare the food coating agent of Example 1.

[0053] (Example 2) 25 g of decolorized shellac PEARL-N811 (manufactured by Gifu Shellac Co., Ltd.), 50 g of tannic acid (“G tannic acid” manufactured by Gokyo Hood & Chemical Co., Ltd.), and 225 g of ethanol were mixed to prepare the food coating agent of Example 2.

[0054] (Example 3) 25 g of decolorized shellac PEARL-N811 (manufactured by Gifu Shellac Co., Ltd.), 0.2 g of tannic acid (“G tannic acid” manufactured by Gokyo Hood & Chemical Co., Ltd.), and 75 g of ethanol were mixed to prepare the food coating agent of Example 3.

[0055] (Comparative Example 1) A sample without any treatment was regarded as the untreated sample and used as Comparative Example 1.

[0056] (Comparative Example 2) A sample using 500 g of ethanol as the coating agent was used as Comparative Example 2.

[0057] (Comparative Example 3) 25 g of tannic acid (“G tannic acid” manufactured by Gokyo Hood & Chemical Co., Ltd.) and 75 g of ethanol were mixed to form the composition of Comparative Example 3.

[0058] (Comparative Example 4) 25 g of decolorized shellac PEARL-N811 (manufactured by Gifu Shellac Co., Ltd.) and 75 g of ethanol were mixed to form the composition of Comparative Example 4.

[0059] (Test Example 1) Using cherry tomatoes, each composition of Examples 1 to 3 and Comparative Examples 2 to 4 was spray-coated (10 μm film thickness) on the surface, and a coating film was formed by natural drying. The samples were left standing indoors, and the spoilage situation after one month was visually confirmed.

[0060] (Test Example 2) Using cherry tomatoes, each composition of Examples 1 to 3 and Comparative Examples 2 to 4 was spray-coated (10 μm film) on the surface, and a coating film was formed by natural drying. The samples were left standing indoors for one week, and the taste was confirmed.

[0061] (Test Example 3) The comparative example 4 and the compositions of Examples 1 to 3 were coated on a transparent PET film with a bar coater #8, and after drying at 60°C for 5 minutes, a coating film was formed. The antibacterial test was carried out on the coated film in accordance with JIS Z2801:2012. · Size, thickness, shape Size: 50 mm × 50 mm, thickness: less than 1 mm, shape: smooth · Test method JIS Z 2801:2012 Antibacterial processed products - Antibacterial test method - Antibacterial effect · Test strain Escherichia coli NBRC 3972 (E. coli) · Test bacterial solution inoculation amount 0.4 mL · Coated film Stomacher film Size: 40 mm × 40 mm, thickness: about 0.09 mm, shape: smooth · Method for measuring viable cell count Agar plate culture method

[0062] (Test Example 4) The composition of comparative example 4 and the compositions of Examples 1 to 3 were coated on a transparent PET film with a bar coater #8, and after drying at 60°C for 5 minutes, a coating film was formed. The state of the coating film after immersing the coated film in water at 25°C for 1 hour was confirmed.

[0063] The results of Test Examples 1 to 2 are shown in Table 1.

[0064] The results of Test Examples 3 to 4 are shown in Table 2

[0065]

Table 1

[0066] Comparative Example 1 (Spoilage situation) ◎: Surface gloss maintained 〇: Surface wrinkles present △: Shrinking present ×: Mold growth Comparative Example 2 (Taste) ◎: Normal 〇: Slightly bitter △: Bitter ×: Strongly bitter

[0067]

Table 2

[0068] Test Example 3 2 or more: antibacterial activity present; less than 2: no antibacterial activity Test Example 4 ◎: no change; 〇: partial whitening; △: partial dissolution and peeling; ×: complete dissolution and peeling

Claims

**Claim 1** A food coating agent characterized by containing shellac, tannic acid, and ethanol. **Claim 2** The food coating agent according to claim 1, wherein the mass ratio of shellac to tannic acid is shellac:tannic acid = 100:1 to 100:

100. **Claim 3** A food coated with the food coating agent according to claim 1 or 2. **Claim 4** A food packaging material coated with the food coating agent according to claim 1 or 2. **Claim 5** A method for extending the shelf life, characterized by coating a food with the food coating agent according to claim 1 or 2.