Fermented food producing container and method for producing fermented food

Abstract

To provide a fermented food producing container and a method for producing a fermented food, which can provide a tasty fermented food.SOLUTION: This fermented food producing container is for receiving a raw material of a fermented food to produce the fermented food. At least a part of a container body is formed by a resin containing a 4-methyl-1-pentene-based polymer.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a vessel for producing fermented foods and a method for producing fermented foods. [Background technology]

[0002] Various fermented foods are produced by placing raw materials in a production container and fermenting them with microorganisms. A wide variety of fermented foods have been produced since ancient times all over the world and are incorporated into daily dietary life, and there is a great demand for delicious fermented foods. Fermented foods are characterized by the fact that their taste and aroma change from the raw materials during the fermentation process, and the deliciousness of fermented foods comes from the fact that the undesirable taste and aroma of the raw materials are not felt, and the fermented foods have their own unique umami taste and aroma. Conventionally, containers for producing fermented foods have been barrels made of wood such as cedar or cypress, tanks made of metal such as stainless steel, pots and jars made of ceramics, etc. In particular, containers for producing rice bran pickles were mainly made of wood barrels and ceramics in the past, but since rice bran pickles are often produced at home, polypropylene (PP) containers are becoming more popular because the containers do not spoil, they do not develop mold, they are easy to handle, and they are low-cost.

[0003] 4-Methyl-1-pentene polymers have excellent properties such as transparency, heat resistance, and releasability, and are used in applications such as release films, electrical components, food packaging materials, tableware, cosmetic containers, and laboratory equipment. As a food packaging material, a packaging material for preserving fermented foods formed of a resin made of a 4-methyl-1-pentene polymer is known (Patent Document 1). It has been reported that the 4-methyl-1-pentene polymer has excellent gas permeability, so that the packaging material is unlikely to burst even when fermented foods are preserved, and is also lightweight and easy to process, making it useful for carrying. However, it has only been shown that this packaging material can preserve fermented foods, which generate a lot of gas during fermentation, for a long period of time without changing the taste, and is not used in the production of fermented foods. In other words, it is not known how the 4-methyl-1-pentene polymer affects the deliciousness of fermented foods. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2001-019030 A Summary of the Invention [Problem to be solved by the invention]

[0005] In view of the above-mentioned background technology, an object of the present invention is to provide a fermented food production vessel and a method for producing fermented foods, which can produce delicious fermented foods. [Means for solving the problem]

[0006] The present inventors have conducted extensive research to solve the above problems, and as a result have found that the above problems can be solved by providing the following configuration, which has led to the completion of the present invention. The present invention relates to, for example, the following items [1] to [8]. [1] A container for producing fermented foods by putting raw materials for fermented foods therein, wherein at least a portion of the container body is formed from a resin containing a 4-methyl-1-pentene polymer. [2] The container according to [1], wherein the 4-methyl-1-pentene polymer is at least one selected from a homopolymer of 4-methyl-1-pentene and a copolymer of 4-methyl-1-pentene and another monomer copolymerizable with 4-methyl-1-pentene. [3] The container according to [1] or [2], wherein the 4-methyl-1-pentene polymer satisfies all of the following requirements (1) to (3): Requirement (1): The melt flow rate (MFR) measured in accordance with ASTM D1238 at 260°C under a load of 5.0 kg is 1 to 500 g / 10 min; Requirement (2): Density measured according to JIS K7112 (density gradient tube method) is 820 to 860 kg / m 3 Is: Requirement (3): The melting point (Tm) measured by differential scanning calorimetry (DSC) is 200°C to 260°C. [4] The container according to any one of [1] to [3], further comprising a lid formed of a resin containing a 4-methyl-1-pentene polymer.

[0007] [5] The container according to any one of [1] to [4], wherein the fermented food is a fermented pickle. [6] The container according to [5], wherein the fermented pickles are pickled in rice bran. [7] A method for producing a fermented food, comprising the following steps (1) to (4): Step (1) placing the rice bran bed into a fermented food production vessel described in any one of [1] to [6]; Step (2) soaking the raw food in the rice bran bed; Step (3) storing the pickled raw food at 0°C or higher for 12 hours or more to ferment; Step (4): The fermented raw food material is removed. [8] The manufacturing method described in [7], wherein the bran bed after step (4) is used again as the bran bed for step (2), followed by steps (3) and (4). Effect of the Invention

[0008] According to the present invention, a fermented food production vessel and a method for producing fermented foods that can produce delicious fermented foods can be provided. [Brief description of the drawings]

[0009] [Figure 1] 1 is a graph showing the results of a sensory evaluation of the rice bran pickles produced using the containers of Examples 1 and 2, and Comparative Examples 1 and 2. The vertical axis indicates the ranking of deliciousness, and each column indicates the number of times the pickles were soaked. [Diagram 2] 2 is a graph showing the measurement results of the ethanol content of the bran-pickled foods produced using the containers of Examples 1 and 2, and Comparative Examples 1 and 2. The vertical axis is the ethanol content (the peak intensity of ethanol measured with an odor sensor), and each column indicates the number of times of pickling. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Next, the present invention will be described in detail. Unless otherwise specified, the expression "A to B" regarding a numerical range means from A to B. Additionally, % means mass %.

[0011] <Fermented food manufacturing container> One aspect of the present invention is a container for producing fermented foods by putting raw materials for fermented foods into the container, wherein at least a portion of the container body is formed from a resin containing a 4-methyl-1-pentene polymer. The fermented food production container has only to have at least a portion of the container body formed from a resin containing a 4-methyl-1-pentene polymer, and that portion may be located anywhere on the container body, for example, the side or bottom. In the fermented food production container, the portion of the container body that comes into contact with the raw materials of the fermented food is preferably formed from a resin containing a 4-methyl-1-pentene polymer. In order to easily achieve the effects of the present invention, it is preferable that the entire container body of the fermented food production container is formed from a resin containing a 4-methyl-1-pentene polymer.

[0012] The shape and size of the fermented food production vessel body are not particularly limited and can be appropriately determined depending on the type and amount of fermented food to be produced. The shape of the opening (or bottom surface) of the main body of the fermented food production vessel may be, for example, approximately square, round, or elliptical, with approximately square being preferred.

[0013] The thickness of the fermented food production container body is not particularly limited and can be determined appropriately depending on the type and amount of fermented food to be produced, but is preferably 0.5 to 20 mm, more preferably 1 to 8 mm, and even more preferably 1 to 5 mm, as this provides excellent strength.

[0014] The fermented food production vessel may be provided with a removable lid to prevent contamination and to adjust the fermentation environment. The material of the lid is not particularly limited, and may be any known material used for lids of food containers, such as resins containing 4-methyl-1-pentene polymers, polyethylene (PE), polypropylene (PP), polystyrene (PS), polydimethylsiloxane (PDMS), glass, fine ceramics, ceramics, etc., and preferably resins containing 4-methyl-1-pentene polymers.

[0015] The thickness of the lid is not particularly limited and can be determined appropriately depending on the type and amount of fermented food to be produced, but is preferably 0.5 to 20 mm, more preferably 1 to 8 mm, and even more preferably 1 to 5 mm, in order to provide excellent strength.

[0016] The fermented food production vessel preferably further includes a lid formed of a resin containing a 4-methyl-1-pentene polymer, since this allows fermentation to be regulated and more delicious fermented food to be obtained.

[0017] The fermented food production container may further include a packing for improving adhesion between the container body and the lid. The material of the packing is not particularly limited, and any known material used for packing for food containers can be used, such as rubbers such as silicone rubber, fluororubber, ethylene propylene rubber, nitrile rubber, styrene butadiene rubber, butyl rubber, and natural rubber.

[0018] The method for producing the fermented food production container of the present invention is not particularly limited, and the equipment used for production is also not limited. A container having a desired shape may be directly molded by a method such as injection molding or blow molding using a resin containing a 4-methyl-1-pentene polymer. Alternatively, a film or sheet formed from a resin containing a 4-methyl-1-pentene polymer may be formed, and the film or sheet may be molded into a container having a desired shape.

[0019] <Resin containing 4-methyl-1-pentene polymer> At least a part of the container body of the fermented food production container is formed from a resin containing a 4-methyl-1-pentene polymer. The 4-methyl-1-pentene polymer is preferably at least one selected from a homopolymer of 4-methyl-1-pentene and a copolymer of 4-methyl-1-pentene and another monomer copolymerizable with 4-methyl-1-pentene.

[0020] Examples of monomers copolymerizable with 4-methyl-1-pentene include at least one selected from ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene). Specific examples of α-olefins having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4,4-dimethyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene. Of these, preferred are α-olefins having 6 to 20 carbon atoms, excluding 4-methyl-1-pentene, and more preferred are α-olefins having 10 to 20 carbon atoms. Ethylene and these α-olefins can be used alone or in combination of two or more. .

[0021] The composition of the 4-methyl-1-pentene polymer is not particularly limited, but from the viewpoint of gas permeability and mechanical strength, the constituent units derived from 4-methyl-1-pentene are preferably 50 mol% or more, more preferably 80 mol% or more, even more preferably 90 mol% or more, and particularly preferably 95 to 100 mol%, and the total amount of the constituent units derived from at least one selected from ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) is preferably 50 mol% or less, more preferably 20 mol% or less, even more preferably 10 mol% or less, and particularly preferably 0 to 5 mol%. However, the total of the constituent units derived from 4-methyl-1-pentene and the constituent units derived from at least one selected from ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) is 100 mol%.

[0022] In the present invention, the amount of the constituent units derived from 4-methyl-1-pentene and the constituent units derived from at least one olefin selected from ethylene and an α-olefin having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) in the 4-methyl-1-pentene polymer can be adjusted by the amount of each olefin added during the polymerization reaction.

[0023] The 4-methyl-1-pentene polymer preferably satisfies one or more of the following requirements (1) to (3), and more preferably satisfies all of the following requirements (1) to (3).

[0024] (Requirement (1)) The melt flow rate (MFR) measured in accordance with ASTM D1238 at 260°C under a load of 5.0 kg is 1 to 500 g / 10 min. This MFR is preferably 5 to 400 g / 10 min, more preferably 5 to 300 g / 10 min, and further preferably 10 to 200 g / 10 min. If the MFR of the 4-methyl-1-pentene polymer satisfies such a range, it is preferable in terms of resin fluidity during production of a fermented food production container, and the processability is good, which is industrially advantageous, and it is preferable because it is possible to mold a fermented food production container with few defects and excellent mechanical strength. The MFR of the 4-methyl-1-pentene polymer can be adjusted by making hydrogen coexist in the reactor during the polymerization reaction.

[0025] (Requirement (2)) The density measured according to JISK7112 (density gradient tube method) is 820-860kg / m 3 The density is preferably 825 to 850 kg / m 3 More preferably, it is 830 to 840 kg / m 3 When the density of the 4-methyl-1-pentene polymer satisfies this range, the polymer is lightweight and easy to carry. The density of the 4-methyl-1-pentene polymer can be adjusted by the amount of a monomer other than 4-methyl-1-pentene to be copolymerized with 4-methyl-1-pentene.

[0026] (Requirement (3)) The melting point (Tm) measured by a differential scanning calorimeter (DSC) is 200 to 260°C. This melting point (Tm) is preferably 210 to 250°C, more preferably 220 to 250°C. If the melting point (Tm) of the 4-methyl-1-pentene polymer is in such a range, the resulting fermented food production container has excellent heat resistance, which is preferable. The melting point (Tm) of the 4-methyl-1-pentene polymer can be adjusted by the amount of a monomer other than 4-methyl-1-pentene to be copolymerized with 4-methyl-1-pentene, or the like.

[0027] The 4-methyl-1-pentene polymer may have only structural units derived from raw material monomers derived from fossil fuels, may have only structural units derived from raw material monomers derived from biomass, or may have both structural units derived from raw material monomers derived from fossil fuels and structural units derived from raw material monomers derived from biomass. Examples of the raw material monomers include ethylene and α-olefins.

[0028] Biomass-derived feedstock monomers are feedstock monomers made from any (renewable) natural raw material, such as from plants or animals, including fungi, yeasts, algae and bacteria, as well as their residues. Biomass-derived feedstock monomers include, for example, those that contain carbon 14 C isotope 1×10 -12 and has a biomass carbon concentration (unit: pMC) of about 100 pMC as measured in accordance with ASTM D6866. The biomass-derived raw material monomer can be obtained, for example, by a conventionally known method.

[0029] A 4-methyl-1-pentene polymer having a structural unit derived from a raw material monomer derived from biomass is preferable from the viewpoint of reducing the environmental load (mainly reducing greenhouse gas emissions).

[0030] If the production conditions such as the polymerization catalyst, polymerization process, and polymerization temperature are the same, the following can be obtained: 14 C isotope 1.0×10 -14 ~1.0×10 -12 The molecular structure and physical properties, etc., other than the content in a ratio of about 100 to 150% are equivalent to those of a 4-methyl-1-pentene polymer having only structural units derived from raw material monomers derived from fossil fuels. Therefore, the performance of a 4-methyl-1-pentene polymer having structural units derived from raw material monomers derived from biomass is considered to be equivalent to that of a 4-methyl-1-pentene polymer having only structural units derived from raw material monomers derived from fossil fuels.

[0031] In the present invention, the 4-methyl-1-pentene polymer may be obtained by any method, and is not particularly limited, but can be produced by polymerizing 4-methyl-1-pentene and, if necessary, at least one olefin selected from ethylene and an α-olefin having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) in the presence of an olefin polymerization catalyst. The 4-methyl-1-pentene polymer may be produced by pyrolyzing a high molecular weight 4-methyl-1-pentene polymer, or may be purified by a method such as solvent fractionation for fractionation based on the difference in solubility in a solvent or molecular distillation for fractionation based on the difference in boiling point.

[0032] As the olefin polymerization catalyst, a conventionally known olefin polymerization catalyst such as a Ziegler catalyst containing a titanium compound, or a metallocene catalyst containing a metallocene compound can be used. Examples of olefin polymerization catalysts for producing 4-methyl-1-pentene polymers suitable for producing fermented food production containers include the olefin polymerization catalysts described in JP-A-2015-183332. The 4-methyl-1-pentene polymer may be a homopolymer of 4-methyl-1-pentene or a copolymer of 4-methyl-1-pentene and another monomer copolymerizable with 4-methyl-1-pentene, which has been further graft-modified.

[0033] In the present invention, a commercially available 4-methyl-1-pentene polymer may be used as the 4-methyl-1-pentene polymer, and preferably a commercially available 4-methyl-1-pentene polymer that satisfies all of the above-mentioned requirements (1) to (3) is used. An example of a commercially available 4-methyl-1-pentene polymer is TPX (trade name) manufactured by Mitsui Chemicals, Inc.

[0034] The resin containing the 4-methyl-1-pentene polymer used in the present invention may be a 4-methyl-1-pentene polymer blended with other resins within the scope of not impairing the object of the present invention. Other resins that can be blended with the 4-methyl-1-pentene polymer are preferably polyolefins such as ethylene-α-olefin copolymers, ethylene-α-olefin-non-conjugated polyene copolymers, propylene-α-olefin copolymers (block copolymers, random copolymers), polypropylene, polybutene-1, butene-1 copolymers, etc., and in particular, polybutene-1 and butene-1 copolymers are preferred in terms of moldability. The ratio of other resins blended with the 4-methyl-1-pentene polymer is preferably 1 to 40% by weight, more preferably 5 to 20% by weight, based on the total weight of the 4-methyl-1-pentene polymer. The blending method can be any known dry blending or melt blending, and is not particularly limited.

[0035] Furthermore, the resin containing the 4-methyl-1-pentene polymer used in the present invention may contain various additives that are usually added as necessary within the range that does not impair the object of the present invention. Examples of the additives include pigments, antifogging agents, slip agents, antiblocking agents, etc.

[0036] 4-methyl-1-pentene polymers have excellent gas permeability due to their unique molecular structure, and excellent water repellency due to the surface methyl groups. Therefore, the fermented food production container of the present invention can regulate the growth of aerobic microorganisms and facultative anaerobic microorganisms and produce delicious rice bran pickles. Since the 4-methyl-1-pentene polymer does not undergo hydrolysis and has excellent water resistance, boiling water resistance, and steam resistance, the fermented food production container of the present invention can be sterilized with high-pressure steam before use. In addition, since the 4-methyl-1-pentene polymer has a high visible light transmittance (usually 90% or more), the food placed in the fermented food production container of the present invention can be easily observed even during production. The 4-methyl-1-pentene polymer can be heat-sealed, and can be easily thermally bonded not only to itself but also to other materials. In addition, since it can be thermoformed, it can be easily molded into a container of any shape, and for example, it can be easily molded using the imprint method or the insert method.

[0037] The "resin containing 4-methyl-1-pentene polymer" relating to the lid formed from the resin containing 4-methyl-1-pentene polymer is as explained in the section "resin containing 4-methyl-1-pentene polymer".

[0038] <Fermented foods> Fermented foods are foods produced by fermentation using microorganisms. Examples of fermented foods include brewed foods such as sake, vinegar, miso, and soy sauce; fermented dairy foods such as yogurt and cheese; fermented pickles such as bran pickles, takuan, senmaizuke, shibazuke, narazuke, kimchi, bettarazuke, and 358zuke; agricultural fermented foods made by fermenting agricultural products such as natto; livestock fermented foods such as prosciutto and dry sausage made by fermenting livestock products such as beef, pork, and chicken; and seafood fermented foods made by fermenting marine fish such as horse mackerel, bonito, and squid, river fish, shellfish, shrimp, and crab (e.g., kusaya, bonito flakes, shiokara, and funazushi). Since the effects of the present invention are easily achieved, the fermented food is preferably a fermented pickle, more preferably a fermented pickle in which lactic acid bacteria are mainly involved, such as rice bran pickles, takuan, senmaizuke, shibazuke, narazuke, and kimchi, and even more preferably a rice bran pickle.

[0039] The raw materials for fermented foods refer to raw food materials, microorganisms, materials for providing an environment necessary for the maintenance or proliferation of the microorganisms, seasonings, and the like.

[0040] Nukazuke is a fermented pickle made by adding and then removing new food ingredients from a bed of bran. Rice bran beds are usually made by mixing rice bran, salt, and water, soaking vegetables in them, and removing the vegetables after a certain period of time (also called discarding). This process is repeated for two to three months for primary maturation. The purpose of primary maturation is to transfer microorganisms such as lactic acid bacteria and yeast attached to the vegetables to the rice bran bed and to grow the microorganisms in the rice bran bed. Since yeast, lactic acid bacteria, etc. are present in a balanced manner in the rice bran bed after primary maturation, fermented foods produced by pickling in the rice bran bed after primary maturation do not have the undesirable taste or aroma of the raw food, and instead have the umami and aroma components unique to rice bran pickles. The rice bran pickles are obtained by soaking the raw food in the rice bran bed after the first maturation and removing the food after a certain period of time. By repeating the soaking and removal of the raw food, the rice bran bed undergoes secondary maturation, and the obtained rice bran pickles gradually become more delicious.

[0041] Rice bran bed is usually made by mixing 100 parts by mass of rice bran with 10 to 15 parts by mass of salt and 80 to 150 parts by mass of water, and then fermenting them appropriately. Usually, rice bran refers to rice bran, and either raw rice bran or roasted rice bran can be used. The rice bran bed contains one or more of the microorganisms found in a normal, well-maintained rice bran bed, such as lactic acid bacteria and yeast, and preferably contains lactic acid bacteria and yeast.

[0042] The raw food for the bran pickles is not particularly limited, and known foods can be used. Examples of the raw food for the bran pickles include cruciferous vegetables such as radish, broccoli, cabbage, cauliflower, kale, Chinese cabbage, arugula, turnip, wasabi, and watercress; nightshade vegetables such as eggplant, tomato, green pepper, paprika, and potato; parsley vegetables such as carrot and celery; melon vegetables such as cucumber, pumpkin, bitter melon, and zucchini; fruits such as watermelon, melon, cherry, mango, and avocado; and processed foods such as tofu, boiled eggs, cheese, and konjac. The raw food material for the bran pickles is preferably a vegetable, more preferably a cruciferous vegetable, and even more preferably a radish, as this is the most effective way to achieve the effects of the present invention.

[0043] <How to manufacture fermented foods> One aspect of the present invention is a method for producing a fermented food, comprising the following steps (1) to (4). Step (1) Place the rice bran bed in the fermented food production vessel. Step (2): Soak the raw food in the rice bran bed. Step (3) The pickled raw food is stored at 0°C or higher for 12 hours or more to ferment. Step (4): The fermented raw food material is removed.

[0044] Step (1) is the process of placing the rice bran bed into the fermented food production vessel. The rice bran bed is explained in the "Fermented Foods" section. The bran bed in step (1) may be at any stage of maturation, so long as it is obtained after the bran, salt, and water have been mixed. That is, the bran bed in step (1) may be one before the start of primary maturation, one after the start of secondary maturation and after the start of secondary maturation. It is preferable to place the bran bed before the start of primary maturation in the fermented food production vessel and carry out only primary maturation, or both primary and secondary maturation in the vessel, but it is also possible to carry out primary maturation in a separate vessel and then place the bran bed after the start of secondary maturation in the fermented food production vessel.

[0045] Step (2) is a process of soaking the raw food in the rice bran bed placed in the fermented food production vessel in step (1). The rice bran bed is the rice bran bed after the first maturation. Soaking the raw food material means that at least a part of the raw food material is immersed in or brought into contact with the rice bran bed, and preferably the whole of the raw food material is immersed in the rice bran bed.

[0046] Step (3) is a process in which the raw food materials soaked in the rice bran bed in step (2) are stored at or above 0°C for at least 12 hours to ferment. Storage is preferably carried out at a temperature of 15° C. to 30° C. for 12 hours or more. It is preferable that step (3) is carried out with the fermented food production vessel covered.

[0047] Step (4) is a process for removing the raw food material fermented in step (3). It is preferable to wash the removed raw food material with water to remove any adhering rice bran bed before eating.

[0048] It is preferable to use the bran bed after step (4) again as the bran bed for step (2), followed by steps (3) and (4), and more preferably to include a step of stirring the entire bran bed after step (4), and even more preferably to repeat this series of steps multiple times. This allows the bran bed to undergo secondary maturation, making the resulting bran pickles more delicious. EXAMPLES

[0049] The present invention will now be described in more detail with reference to examples, but the present invention is not limited to these.

[0050] <Measurement of polymer properties>

[0051] (Melt Flow Rate (MFR)) The MFR was measured at a temperature of 260° C. and a load of 5.0 kg in accordance with ASTM D1238.

[0052] (density) The density was measured using a density gradient tube in accordance with JIS K7112.

[0053] (Melting point (Tm)) A heat-endothermic curve was obtained using a DSC measuring device (DSC220C) manufactured by Seiko Instruments Inc., and the temperature at the maximum melting peak position during heating was taken as the melting point (Tm). The measurement was performed as follows. Approximately 5 mg of a pellet sample was packed into an aluminum pan for measurement, and the temperature was raised from 20°C to 280°C at a heating rate of 10°C / min, and then held at 280°C for 5 minutes, and then cooled to 20°C at a cooling rate of 10°C / min. After that, the temperature was raised again from 20°C to 280°C at a heating rate of 10°C / min, and then cooled again to 50°C at a cooling rate of 50°C / min. The melting peak that appeared during the second heating was taken as the melting point (Tm). The heat of fusion was also calculated from the melting peak. When there were multiple melting peaks, the value with the strongest peak intensity was taken as the melting point.

[0054] <Examples 1 and 2, Comparative Examples 1 and 2> The rice bran pickles were produced by the method described below, and the resulting rice bran pickles were evaluated. (Preparing the container) The following containers A to D were prepared as containers for producing rice bran pickles. Containers A to D are composed of a body (capacity 520 mL) with dimensions of 203 mm wide x 100 mm deep x 55 mm high, a silicone rubber gasket, and a lid. The bottom and opening of the container body are roughly rectangular in shape. The thickness of the body and the lid is 3.5 mm. The materials of the body and lid are as shown in Table 1 below.

[0055] [Table 1]

[0056] As a 4-methyl-1-pentene polymer, TPX (registered trademark) RT31XB (manufactured by Mitsui Chemicals, Inc., MFR: 21 g / 10 min, density: 833 kg / m 3 , melting point 232°C) was used. The body and the lid were manufactured by melt molding 4-methyl-1-pentene based polymer or a commercially available moldable polypropylene.

[0057] (Making rice bran bed) 192g of salt was added to 1600g of rice bran (Kokujo Sangyo Co., Ltd., roasted rice bran for pickles) and mixed until the mixture was uniform. Then, 800ml of tap water was added little by little and kneaded, and the mixture was kneaded by hand to form a lump to make a rice bran bed. 450g of this lump of rice bran bed was filled into each of 520ml containers A to D, which each have a container body and a container lid.

[0058] (First maturation of rice bran bed) 5.2g of paprika, 10g of cabbage, 5g of dried shiitake mushrooms, and 5g of dashi kelp were mixed into each test section. After that, they were stored at 20℃, and the rice bran bed in each container was stirred once a day by turning it upside down. This operation was continued for one week. After one week, the mixed paprika, cabbage, dried shiitake mushrooms, and dashi kelp were removed, and 16g of paprika, 6g of cabbage, 2g of dried shiitake mushrooms, and 0.5g of dashi kelp were mixed into each container. The rice bran beds in each container were then stirred once a day for another week.

[0059] (Secondary maturation of rice bran bed and production of rice bran pickles) After the above primary maturation (two weeks had passed since the start of the primary maturation), the rice bran bed was ready for the production of rice bran pickles, so the production of rice bran pickles began. One approximately cylindrical radish was divided into three equal parts in the horizontal direction of the cylinder to obtain three cylindrical radishes. Next, each cut approximately cylindrical radish was divided into four equal parts in a fan shape vertically to the cylinder and adjusted to 40 g. At this time, the radish cut pieces cut for mass adjustment were used as test pieces for initial evaluation. The whole of the fan-shaped radish was rubbed with salt, left at room temperature for 5 minutes, and the water that had seeped out was lightly wiped off. The radish was soaked in each container, covered, and each container was left at 20 ° C. After 1 day, the soaked radish was taken out and the bran was washed off to obtain bran pickles. After removing the pickled radishes, the bran bed was stirred and new radishes were then pickled. The pickling of new radishes was repeated every day for a total of six times, allowing the rice bran bed to undergo a secondary maturation while producing rice bran pickles.

[0060] The primary and secondary aging of the rice bran bed and the production of rice bran pickles were carried out under conditions that did not cause over-fermentation of the rice bran bed. In addition, since radish is larger than other vegetables and multiple test pieces can be obtained from one solid, it is suitable for testing to compare the taste of pickled rice bran by producing pickled rice bran under multiple experimental conditions. Therefore, radish pickled rice bran was produced.

[0061] (Rating of pickled vegetables) (1) Sensory evaluation method The pickled rice bran obtained above was cut into pieces 5-8 mm wide along the longitudinal axis and tasted by three expert sensory evaluators. They then ranked the pickled rice bran pieces in order of how delicious they felt. They also had to freely describe their evaluation of the taste.

[0062] (2) Method for measuring ethanol content The top of the pickled rice bran was cut off in 20-25g portions, and an equal amount of water was added to the pieces, which were then crushed in a homogenizer to form a slurry. 1.0g portions of the slurry were taken and the volatile components were measured using an odor sensor (Flash GC Nose Heracles NEO, manufactured by Alphamos). Several types of volatile components were detected, and the amount of ethanol, which is an indicator of the degree of fermentation, was compared relatively from the peak area ratio.

[0063] (3) Sensory evaluation results The ranking of deliciousness is shown in Figure 1. In Figure 1, "TPX-TPX" indicates Example 1, "PP-TPX" indicates Example 2, "TPX-PP" indicates Comparative Example 1, and "PP-PP" indicates Comparative Example 2. The results showed that Examples 1 and 2 tasted better than Comparative Examples 1 and 2. By using a container body formed from a resin containing a 4-methyl-1-pentene polymer, delicious rice bran pickles were obtained. In addition, the free description of the sensory evaluation for Examples 1 and 2 was summarized as follows: the radish had no grassy taste, spiciness, or odor, and the umami and aroma unique to the pickled rice bran was felt. The free description for Comparative Examples 1 and 2 was summarized as follows: the grassy taste and spiciness of the radish remained in the mouth, and the umami and aroma unique to the pickled rice bran were not sufficient.

[0064] (4) Ethanol content measurement results The ethanol contents are shown in Figure 2. In Figure 2, "TPX-TPX" indicates Example 1, "PP-TPX" indicates Example 2, "TPX-PP" indicates Comparative Example 1, and "PP-PP" indicates Comparative Example 2. Various microorganisms, mainly lactic acid bacteria and yeasts, live in the rice bran bed. Lactic acid bacteria can be classified into those that perform homolactic fermentation, which does not produce alcohol, and those that perform heterolactic fermentation, which produces alcohol. Yeast also breaks down sugar and produces alcohol and carbon dioxide. Therefore, if the yeast and / or lactic acid bacteria that perform heterolactic fermentation in the rice bran bed grow, alcohol will be produced, so the ethanol content of the rice bran pickles can be said to be one indicator of the progress of fermentation. Examples 1 and 2 had a higher ethanol content than Comparative Examples 1 and 2, and it was considered that fermentation had progressed more than in Comparative Examples 1 and 2. It was revealed that by using the manufacturing vessels of Examples 1 and 2, the rice bran bed was allowed to mature in a short period of time.

Claims

1. A container for producing fermented foods by putting raw materials for the fermented foods therein, at least a part of the container body being formed from a resin containing a 4-methyl-1-pentene polymer.

2. The container according to claim 1, wherein the 4-methyl-1-pentene polymer is at least one selected from a homopolymer of 4-methyl-1-pentene and a copolymer of 4-methyl-1-pentene and another monomer copolymerizable with 4-methyl-1-pentene.

3. The container according to claim 1, wherein the 4-methyl-1-pentene polymer satisfies all of the following requirements (1) to (3): Requirement (1): The melt flow rate (MFR) measured in accordance with ASTM D1238 at 260°C under a load of 5.0 kg is 1 to 500 g / 10 min; Requirement (2): Density measured according to JIS K7112 (density gradient tube method) is 820 to 860 kg / m 3 Is: Requirement (3): The melting point (Tm) measured by differential scanning calorimetry (DSC) is 200° C. to 260° C.

4. 2. The container according to claim 1, further comprising a lid formed of a resin containing a 4-methyl-1-pentene polymer.

5. 2. The container of claim 1, wherein the fermented food is a fermented pickle.

6. The container according to claim 5, wherein the fermented pickles are pickled in rice bran.

7. A method for producing a fermented food, comprising the following steps (1) to (4): Step (1): Place the rice bran bed into the fermented food production vessel according to claim 1; Step (2) soaking the raw food in the rice bran bed; Step (3) storing the pickled raw food at 0° C. or higher for 12 hours or more to ferment; Step (4): The fermented raw food material is removed.

8. The method according to claim 7, wherein the bran bed after step (4) is used again as the bran bed in step (2), followed by steps (3) and (4).

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