CN116828993A - Method for producing crosslinked protein - Google Patents

Abstract

The present invention aims to provide a novel processing technique for improving the crosslinkability of a vegetable protein material. By allowing polysaccharides and a multi-copper oxidase to act on a vegetable protein, the crosslinking effect of the vegetable protein can be improved.

Description

Method for producing crosslinked protein

Technical Field

The present invention relates to a method for producing a crosslinked protein. More specifically, the present invention relates to a processing technique for improving the crosslinkability of a vegetable protein.

Background

In recent years, in the food market, the share of vegetable meat-like food materials called replacement meat is increasing. Such meat-like food materials have been paid attention to some consumers such as vegetarian or absolute vegetarian, but the required movement has changed during the years, and have been improved in awareness of health intention, weight loss, environmental problems, animal care, and the like.

Accordingly, various studies have been made on a technique of bonding meat-like food materials in order to manufacture a food which simulates a processed food of minced meat of livestock such as hamburger meat using the meat-like food materials. For example, patent document 1 discloses a method for producing a meat-like food, which is characterized by comprising a granular soybean protein, an isolated soybean protein and a predetermined cation in a weight ratio of 0.005 to 0.1 relative to the isolated soybean protein, mixing and molding cations having a divalent cation of 0.01 or less in a humidity-controlling manner, and heating and bonding by microwave irradiation so that the moisture content is 40 to 70%, in order to produce a food containing a meat-like protein which does not undergo deformation even after cooking and has a springiness. Patent document 2 discloses a method for producing a food containing meat-like particulate protein, which is characterized in that a dry particulate defatted soybean protein is rehydrated with a weak alkali solution or reconstituted with hot water to obtain a particulate defatted soybean protein, and the particulate defatted soybean protein is mixed with a protein or a protein powder, in order to produce a food containing meat-like particulate protein which does not form after cooking and has a juicy texture. Patent document 3 discloses the following: cellulose ether having a thermoreversible gelling property such as methylcellulose is used for processed foods for the purpose of imparting a function such as bondability and shape retention, and is used for producing hamburger meat or sausage as an analogue of edible meat using a plant-based raw material.

On the other hand, various techniques for modifying nonwoven plant protein materials in the form of powder, paste, milk, etc. have been studied. For example, patent document 4 discloses a method of crosslinking proteins using a multi-copper oxidase including laccase, bilirubin oxidase, ascorbate oxidase, ceruloplasmin, and the like.

Prior art literature

Patent literature

Patent document 1: international publication No. 2010/119985

Patent document 2: japanese patent laid-open No. 2013-009617

Patent document 3: japanese patent laid-open No. 2020-029571

Patent document 4: japanese patent laid-open No. 11-276162

Disclosure of Invention

Technical problem to be solved by the invention

Since the meat-like food material is made of vegetable proteins, it has not yet reached a meat-like food in at least any one of the characteristics of cohesiveness, juiciness, liquid retention, digestion rate, yield during processing, and the like (hereinafter, also referred to as "meat-like characteristics"). The processing technology of meat-like food materials has been improved for the purpose of reproducing meat-like properties of livestock at a level closer to that of meat foods, but in the development process, there are many restrictions on the production process, and the obtained meat-like properties are mostly insufficient, and there is still room for improvement. In addition, even if there is a technology capable of exhibiting meat-like characteristics to some extent, in order to follow the diversification of foods using replacement meat, a technology capable of further enhancing the characteristics is desired.

The present inventors have expected that it is useful to improve the crosslinkability of a textured vegetable protein material in order to improve the meat-like properties such as cohesiveness, liquid retention, digestion rate, and yield in processing of the vegetable protein. Therefore, attempts have been made to treat a textured vegetable protein material with a laccase enzyme which is a multicopper oxidase having a protein crosslinking activity, but the effect of improving the meat-like properties of livestock has not been confirmed at all. This is considered to be because the use of the multi-copper oxidase alone cannot exert a high protein crosslinking effect to such an extent that the effect of improving meat-like characteristics of livestock can be exhibited. Accordingly, an object of the present invention is to provide a novel processing technique for improving the crosslinkability of a vegetable protein.

Technical scheme for solving technical problems

The inventors found that: the use of a polysaccharide such as pectin or methylcellulose in a laccase, which is a multi-copper oxidase having protein crosslinking activity, significantly improves the crosslinking properties of vegetable proteins, and further improves the adhesion, liquid retention, digestion rate, yield in processing, and other meat-like properties of the obtained meat-like processed food when applied to the preparation of meat-like processed foods (meat-substitute foods) by the organization of vegetable protein materials. In view of the fact that polysaccharides themselves do not have a crosslinking effect of proteins and that properties (e.g., thickening) of polysaccharides cannot be enhanced when the target of crosslinking by laccase is proteins and polysaccharides coexist, it is entirely unexpected that these components are combined to significantly improve the crosslinking property of a vegetable protein material and that this crosslinking property improving effect is obtained to a degree that the livestock meat-like properties of a meat-like processed food are significantly improved when the composition is applied to the production of a meat-like processed food by organizing a vegetable protein material. The present invention has been completed based on further repeated studies based on this knowledge. That is, the present invention provides the following disclosed embodiments.

A method for producing a crosslinked plant protein, comprising the step of allowing polysaccharides and a copper-rich oxidase to act on a plant protein.

The method according to item 2, wherein the polysaccharide is a thermoreversible gelling agent.

Item 3. The production method according to item 1 or 2, wherein the thermoreversible gelling agent is pectin.

The production method according to any one of items 1 to 3, wherein in the step, a compound selected from betanin (betalain), anthocyanins (anthocyan), curcuminoids (curcuminoid), polyhydroxy chalcone and polyhydroxy anthraquinone is further caused to act.

The method according to any one of items 1 to 3, wherein the step further comprises beet pigment (Japanese bead pigment).

The method according to any one of items 1 to 5, wherein the multi-copper oxidase is laccase and/or bilirubin oxidase.

The method according to any one of items 1 to 6, which comprises a step of allowing the polysaccharide and the multicopper oxidase to act on a textured vegetable protein material to obtain a meat-like processed food,

the vegetable protein is included in the organized vegetable protein material,

The crosslinked vegetable protein is contained in the meat-like processed food.

The cross-linking agent for vegetable proteins, which comprises polysaccharides and a copper-rich oxidase.

Item 9. The crosslinking agent according to item 8, which is used as an adhesion improver for meat-like processed foods using a textured vegetable protein material.

Item 10. The crosslinking agent according to item 8, which is used as a taste modifier for meat-like processed foods using a textured vegetable protein material.

Item 11. The crosslinking agent according to item 8, which is used as a liquid retention enhancer for meat-like processed foods using a textured vegetable protein material.

Item 12. The crosslinking agent according to item 8, which is used as a digestion rate improver for meat-like processed foods using a textured vegetable protein material.

Item 13. The crosslinking agent according to item 8, which is used as a yield-improving agent in the production of meat-like processed foods using a textured vegetable protein material.

The adhesion promoter according to any one of items 8 to 13, wherein the adhesion promoter further comprises a compound selected from the group consisting of betaines, anthocyans, curcuminoids, polyhydroxy chalcones and polyhydroxy anthraquinones.

The adhesion improver according to any one of items 8 to 13, wherein the adhesion improver further comprises a betalain.

Item 16. A meat-like processed food obtained by the production method according to item 7.

Effects of the invention

According to the present invention, a processing technique for improving the crosslinkability of a vegetable protein is provided. By applying this technique to a textured vegetable protein material, the meat-like characteristics such as cohesiveness, liquid retention, digestion rate, and yield in processing of the obtained meat-like processed food can be improved.

Drawings

FIG. 1 shows the results of confirming the crosslinking effect by SDS-PAGE based on the combination of polysaccharides and a copper-rich oxidase in test example 1.

Fig. 2 shows the measurement results of the hardness of the meat-like processed food produced in test example 2.

Fig. 3 is a photograph showing the appearance of the meat-like processed food produced in test example 2.

Fig. 4 shows the measurement results of the hardness of the meat-like processed food produced in test example 3.

Fig. 5 is a photograph showing the appearance of the meat-like processed food produced in test example 3.

Fig. 6 is a photograph showing the appearance of the meat-like processed food produced in test example 5.

Fig. 7 is a photograph showing the appearance of the meat-like processed food produced in test example 5.

Fig. 8 is a photograph showing the appearance of the meat-like processed food produced in test example 5.

Fig. 9 is a photograph showing the appearance of the meat-like processed food produced in test example 5.

Fig. 10 is a photograph showing the appearance of the meat-like processed food produced in test example 5.

Fig. 11 is a photograph showing the appearance of the meat-like processed food produced in test example 5.

Fig. 12 is a photograph showing the appearance of the meat-like processed food produced in test example 5.

Fig. 13 is a photograph showing the appearance of the meat-like processed food produced in test example 5.

FIG. 14 shows the results of a digestion rate test (free amino nitrogen content) of the meat-like processed food produced in test example 7.

FIG. 15 shows the results of a digestion rate test (residue amount) of the meat-like processed food produced in test example 7.

Detailed Description

1. Method for producing crosslinked plant protein

The method for producing a crosslinked vegetable protein of the present invention is characterized by comprising a step of allowing polysaccharides and a copper-rich oxidase to act on a vegetable protein. This can improve the crosslinkability of the plant protein. In a preferred embodiment of the present invention, in this step, a compound selected from the group consisting of betaines, anthocyans, curcuminoids, polyhydroxy chalcones and polyhydroxy anthraquinones may be further allowed to act. Further, when the method for producing a crosslinked vegetable protein of the present invention is applied to a textured vegetable protein material to produce a meat-like processed food, the meat-like characteristics of the obtained meat-like processed food can be improved by improving the crosslinkability of the vegetable protein in the material. The method for producing the crosslinked vegetable protein of the present invention will be described in detail below.

1-1 vegetable proteins

The source of the plant protein is not particularly limited, and examples thereof include: soybean, broad bean, pea, chickpea, mung bean, lupin, kidney bean and other grains; cereal such as barley, rice, wheat, rye, oat, buckwheat, barnyard grass, millet, bran (Teff), quinoa, corn, etc.; hemp (industrial hemp), canary seed (Canary seed), flax seed, peach kernel, cashew, hazelnut, pecan, macadamia nut, pistachio, walnut, brazil nut, peanut, coconut, thunderbolt nut, chestnut, sesame, pine nut and other seeds; algae, and the like.

In the present invention, 1 kind of the above-mentioned vegetable protein may be contained alone or 2 or more kinds of the above-mentioned vegetable protein may be contained as the vegetable protein. Among these vegetable proteins, preferred are proteins of grains and cereal, more preferred are soybean protein, pea protein and wheat protein, and even more preferred are soybean protein and pea protein, from the viewpoint of further improving the crosslinkability, and from the viewpoint of further improving the meat-like characteristics when the production method of the present invention is applied to the production of a meat-like processed food using a textured vegetable protein material.

The form of the vegetable protein used in the present invention is not particularly limited. For example, the material may be in a powder form or a textured form. In the present invention, when a powdered plant protein is used, the powdered plant protein can be used in a state of being dispersed in water. In the present invention, when a textured vegetable protein (hereinafter referred to as "textured vegetable protein material") is used, the textured vegetable protein material can be used in a state of swelling in water.

In the case where the form of the vegetable protein used in the present invention is a tissue form, the vegetable protein is more specifically used in the form of a tissue-formed vegetable protein material. Textured vegetable protein materials are known as alternative meats (simulated meats), and typical examples thereof include materials obtained by extruding, drying, or freezing a raw material mixture containing vegetable protein and water by an extruder or the like to texture the meat.

Examples of the form of the textured vegetable protein material include granular and fibrous forms. Examples of the granular form include a block form having various sizes (the sizes of the small, large, and block forms are increased in this order), such as a small size, a large size, and a block form; a flat shape having various sizes (a size is increased in order of a slice (flag) type, a fillet (file) type, and a slice (slice)) such as a slice type, a fillet type, and a slice type.

More specific examples of the organized plant protein material include granular plant protein and fibrous plant protein. Both the particulate vegetable protein and the fibrous vegetable protein refer to proteins defined in "Japanese agriculture and forestry standards for vegetable proteins". However, the textured vegetable protein material used in the present invention is not limited to this, as long as it is a material textured in a meat-like manner as described above.

The content of the vegetable protein contained in the textured vegetable protein material (based on the dry state of the textured vegetable protein material) is not particularly limited, and examples thereof include 30 wt% or more, 35 wt% or more, and 40 wt% or more. From the viewpoint of further improving the effect of improving the meat-like characteristics, the content is preferably 43% by weight or more, more preferably 45% by weight or more, and still more preferably 50% by weight or more. The upper limit of the content range is not particularly limited, and for example, 90% by weight or less, preferably 80% by weight or less is exemplified.

In addition to the vegetable protein, other raw materials and/or food additives may be included in the textured vegetable protein material as desired. These other materials and/or food additives may be selected, for example, according to the type of "1-6. Meat-like processed food" described later. Examples of the other materials include components which are inevitably present together from food materials containing the above vegetable proteins, edible vegetable oils, extracts and concentrates of animals and plants, protein hydrolysates, and the like. The food additive is not particularly limited as long as it is a food additive acceptable in food, and examples thereof include a tissue improver such as calcium sulfate; flavoring agents such as salt, granulated sugar, spice, sodium L-glutamate, disodium 5' -ribonucleotide, disodium 5' -inosinate, and disodium 5' -guanylate; caramel I, caramel III, caramel IV, cocoa, etc. (excluding "1-4. Specified compounds" described below); antioxidants such as L-ascorbic acid; perfume, etc.

The textured vegetable protein material usable in the present invention may be any of the types of vegetable proteins, characteristics other than the content ratio of vegetable proteins (for example, properties, moisture content, particle size, temperature, raw materials other than food additives, chewing feeling, water retention, foreign matter, content) and methods for measuring the same, and may be determined according to the characteristics and measurement methods defined in "Japanese agriculture and forestry standards for vegetable proteins".

1-2 polysaccharides

The polysaccharide used in the present invention is not particularly limited, and usually a thickening polysaccharide (gelling agent) is used. The thickening polysaccharide may be any one of a thermoreversible gelling agent and a thermoreversible gelling agent.

Examples of the thermoreversible gelling agent include pectin, gellan gum, glucomannan, alginic acid and salts thereof (alkali metal salts such as sodium salt, alkaline earth metal salts such as calcium salt), and the like. Examples of pectins include HM pectins having a Degree of Esterification (DE) of 50% or more and LM pectins having a DE of less than 50%.

Examples of the thermoreversible gelling agent include Methylcellulose (MC), hydroxypropyl cellulose (HPC), hydroxypropyl methylcellulose (HPMC), carrageenan, xanthan gum, gelatin, agar, and starch.

These polysaccharides may be used alone or in combination of 1 or more.

Among these polysaccharides, polysaccharides and derivatives thereof derived from plant cell walls are preferable, and a thermoreversible gelling agent is more preferable, and pectin is further preferable, from the viewpoint of further improving the crosslinking property, and further from the viewpoint of further improving the effect of improving the meat-like characteristics of livestock when the production method of the present invention is used for producing meat-like processed foods using a textured vegetable protein material. The source of pectin is not particularly limited, and examples thereof include citrus peel (e.g., lemon, orange, etc.), apple, beet, etc. Beet as a source of pectin means Beta vulgaris ssp.

Among pectins, in view of further improving the crosslinkability, and in view of further improving the meat-like characteristics when the production method of the present invention is used for producing meat-like processed foods using a textured vegetable protein material, pectins derived from beet are preferable. Among pectins, from the viewpoint of further improving the crosslinkability, HM pectins are preferable, and HM pectins having a DE of 55% or more are more preferable. Alternatively, in the pectin, from the viewpoint of further improving the crosslinkability, and from the viewpoint of further improving the effect of improving the meat-like properties of livestock when the production method of the present invention is used for producing a meat-like processed food using a textured vegetable protein material, it is preferable to use pectin containing ferulic acid, and the content of ferulic acid in the pectin is, for example, 0.3 to 3% by weight, preferably 0.4 to 2% by weight, and more preferably 0.5 to 1% by weight.

Further, from the viewpoint of more strongly sensing the texture (as exemplified by a granular texture) of the texture of the textured vegetable protein material of the meat-like processed food obtained when the production method of the present invention is used for producing the meat-like processed food using the textured vegetable protein material, the thermoreversible gelling agent is preferably selected, pectin is more preferably selected, HM pectin is more preferably selected, and HM pectin having a DE of 55% or more is more preferably selected. Alternatively, among pectins, from the viewpoint of more strongly perceiving the texture (granular texture as an example) of the texture of the obtained meat-like processed food, the texture of the textured vegetable protein material is perceived, and preferably, pectins containing ferulic acid are used, and the content of ferulic acid in the pectins is, for example, 0.3 to 3% by weight, preferably 0.4 to 2% by weight, and more preferably 0.5 to 1% by weight.

The amount of the polysaccharide to be used is not particularly limited, but examples of the amount of the polysaccharide per 100 parts by weight of the vegetable protein include 0.5 to 30 parts by weight, and preferably 2 to 15 parts by weight from the viewpoint of further improving the crosslinkability of the vegetable protein.

In the case where the production method of the present invention is used for producing a meat-like processed food using a textured vegetable protein material, the amount of polysaccharide used is, for example, 0.02 to 20 parts by weight per 100 parts by weight of the textured vegetable protein material (material swelled with water). The amount of the polysaccharide to be used for 100 parts by weight of the textured vegetable protein material (material obtained by swelling with water) is preferably 0.2 to 6 parts by weight, more preferably 0.7 to 4.5 parts by weight, 1.0 to 4 parts by weight, or 1.5 to 3.5 parts by weight, from the viewpoint of further improving the meat-like character of livestock. The state in which the organized plant protein material is swelled with water means a state in which the organized plant protein material absorbs water to a saturated state.

1-3 Multi-copper oxidase

The multi-copper oxidase used in the present invention means a group of enzymes containing a plurality of copper atoms in the molecule and oxidizing polyphenol, methoxyphenol, diamine, bilirubin, ascorbic acid, etc. with molecular oxygen. The number of copper atoms contained in the conventional known enzyme sample is usually 2 to 8, but the number is not particularly limited, since it varies depending on the state of the enzyme standard at the time of analysis and the analysis method. Examples of enzymes classified as multicopper oxidases include laccase, bilirubin oxidase, ascorbate oxidase, and ceruloplasmin.

These multicopper oxidase may be used alone or in combination of 1 or more. Among these multicopper oxidases, laccase is preferable from the viewpoint of further improving the crosslinkability of vegetable proteins, and from the viewpoint of further improving the effect of improving the meat-like properties of livestock when the production method of the present invention is used for producing meat-like processed foods using a textured vegetable protein material.

Laccase is an enzyme with phenol oxidase activity (EC 1.10.3.2). Specific examples of laccase include laccase derived from microorganisms such as fungi and bacteria, more specifically, laccase derived from Aspergillus (Aspergillus), streptomyces (Neurospora), podospora (Podospora), vitis (Botrytis), lysimachia (Collybia), phellinus (Fomes), lentinus (Lentinus), pleurotus (Pleurotus), rhodomycospora (Pycnoprus), pyricularia (Pyricularia), trametes (Trametes), rhizoctonia, hard pore (Rigidoporus), coprinus (Coprinus), psatica (Psatica), myceliophthora (Myceliophaera), acremonium (Schmidium), polyporus (Polytruus), white fungus (Phanerochaete), etc.

These laccases may be used alone or in combination of 1 or more. Among these laccases, from the viewpoint of further improving the crosslinkability of vegetable proteins, and from the viewpoint of further improving the effect of improving the meat-like properties of livestock when the production method of the present invention is used to produce a meat-like processed food using a textured vegetable protein material, laccases derived from Trametes (Trametes) and laccases derived from Aspergillus (Aspergillus) (more preferably from Aspergillus oryzae) are preferable, and laccases derived from Trametes (Trametes) are more preferable.

The amount of the multi-copper oxidase to be used is not particularly limited, and examples of the amount of the multi-copper oxidase per 1g of the plant protein include 5 to 5000U, and 10 to 1000U is preferable from the viewpoint of further improving the crosslinkability of the plant protein.

In the case where the production method of the present invention is used for producing a meat-like processed food using a textured vegetable protein material, the amount of the multi-copper oxidase used is, for example, 1 to 500U, preferably 2 to 400U, more preferably 3 to 300U, 4 to 200U, 5 to 100U, 7.5 to 75U, 10 to 50U, 12.5 to 35U, or 15 to 25U, from the viewpoint of further improving the meat-like property of livestock, as the amount of the multi-copper oxidase per 1g of the textured vegetable protein material (material after swelling with water).

The amount of the polysaccharide-based copper oxidase per 1mg of polysaccharide is, for example, 0.1 to 20U, and from the viewpoint of further improving the crosslinkability of the plant protein, it is preferably 0.4 to 10U, more preferably 0.6 to 7U.

The activity of the multicopper oxidase was measured using 2,2' -biazo-bis [ 3-ethylbenzothiazoline sulfonate ] (ABTS), which is a substrate. ABTS was dissolved in 25mM citrate buffer (pH 3.2) at a concentration of 1.0mg/ml to prepare a substrate solution. After 3.0ml of the substrate solution was preheated at 25℃and 0.1ml of the enzyme solution was added thereto, the mixture was stirred, incubated at 25℃and absorbance at 405nm was measured after 1 minute and after 3 minutes. Under this condition, the amount of enzyme that increases absorbance at 405nm by 1.0OD in 1 minute was defined as 1 unit (U).

1-4. Specified Compounds

In the present invention, in order to further improve the crosslinkability of the vegetable protein and to further improve the meat-like properties (in particular, cohesiveness) of the meat-like processed food using the textured vegetable protein material in the case where the production method of the present invention is used, a predetermined compound, that is, a compound selected from the group consisting of betaines, anthocyanins, curcumins, polyhydroxy chalcones and polyhydroxy anthraquinones, may be used in addition to the polysaccharides and the multi-copper oxidase.

Betalains (betalains) include betacyanins (betacyanins) and betaxanthin (betaxantine). Examples of betalains include: betanin (glycoside of betanin), betanin (betanin), isosbetanin (glycoside of isosbetanin), isosbetanin (aglycone of isosbetanin), pre-betanin (probetanin), neobetanin (neobetanin), etc. Examples of betaxanthin include canthaxanthin, mirabilithin, fraxinin, and Opuntia ficus-indica.

Examples of anthocyanidins include anthocyanins (anthocyans) and anthocyanins (anthocyans) (anthocyanidins). The anthocyanin is polyhydroxy-2-phenylbenzopyrylium (a compound obtained by bonding at least a plurality of phenolic hydroxyl groups in 2-phenylbenzopyrylium as substituents), and examples thereof include pelargonidin, cyanidin (such as rubbernacin and perillartine), delphinidin, hesperidin, luteolin, paeoniflorin, malvidin, morning glory pigment, europinidin (Japanese text: tartan), and rose pigment (rosin). Examples of anthocyanin glycosides include rubobracin (glycoside of procyanidin), perillartine (glycoside of procyanidin), malonyl perillartine (perillartine bonded by malonic acid), and the like.

Examples of the curcumin include curcumin (curcumin), demethoxycurcumin, bisdemethoxycurcumin, and the like.

Examples of the polyhydroxy chalcone (a compound in which at least a plurality of phenolic hydroxyl groups are bonded as substituents) include carthamin (saflomin), carthamin (carthamin), and the like.

Examples of the polyhydric anthraquinone (a compound in which at least a plurality of phenolic hydroxyl groups are bonded as substituents in anthraquinone) include carminic acid.

The above-mentioned predetermined compound may be a chemical compound or a natural compound. In the case where the above-mentioned compound is a natural product, the source is not particularly limited. Examples of the source include plants such as beet (Beta vulgaris ssp. Vulgaris var. Vulgaris (also called edible beet, red beet, beet of beet root)), carrot, purple potato, perilla, purple cabbage, safflower, turmeric; insects, and the like. More specifically, examples of natural products providing the above-mentioned compounds include betalains (including betanin, isostain, betanin, and isostain as betanin), betanin (Phyllocalin), lycopene (Hylocillin), amaranthin (Amaranthin), sequinin-I, II, III (Gomphrenin-I, II, and III), iresinin (Japanese, and crocin-I, II (Celosianin-I, II)), carrot pigments (including, as anthocyanidins, pelargonidin, and procyanidins), purple potato pigments (including, as anthocyanidins, and including, as procyanidins), paeoniflorin (including, as anthocyanidins, and including, as perillain, and including, malonyl perillain), purple (including, as anthocyanins), safflower (including, as rubrofloxacin), and curcumin (including, as crocin, and including, as curcumine (including, and including, curcumin (curcumin)), and curcuma (including, as natural curcuminoids).

The above-mentioned specific compounds may be used alone or in combination of 1 or more.

Among the above-mentioned predetermined compounds, betaines are preferable, and betaines, isostaines, and isostaines are more preferable, from the standpoint of further improving the crosslinkability of vegetable proteins, and from the standpoint of further improving the meat-like properties (in particular, cohesiveness) when the production method of the present invention is used for producing meat-like processed foods using a textured vegetable protein material.

In order to use the above-described predetermined compound, the above-described natural pigment itself may be used. The natural pigment itself (i.e., the natural pigment isolated from the above-mentioned organisms) may be used, the extract containing the pigment compound of the organism containing the pigment compound may be used, and the organism itself containing the pigment compound may be used. In the case of using these isolated natural pigments, extracts and/or organisms themselves, 1 kind of the isolated natural pigments, extracts and organisms themselves may be used alone or in combination. Among these isolated natural pigments, extracts and organisms themselves, beet pigments, beet extracts and beets are preferable, beet extracts and beets are more preferable, and beets are even more preferable, from the viewpoint of further improving the cross-linking properties of vegetable proteins, and from the viewpoint of further improving the meat-like properties (in particular, cohesiveness) of livestock when the production method of the present invention is used to produce meat-like processed foods using textured vegetable protein materials.

The amount of the above-mentioned predetermined compound used is not particularly limited, but examples of the amount of the above-mentioned predetermined compound per 100 parts by weight of the vegetable protein include 0.00005 to 1 part by weight, and preferably 0.0005 to 0.7 part by weight from the viewpoint of further improving the crosslinkability of the vegetable protein. In the case where the production method of the present invention is used for producing a meat-like processed food using a textured vegetable protein material, the amount of the above-mentioned predetermined compound per 100 parts by weight of the textured vegetable protein material (material obtained by swelling with water) may be, for example, 0.00001 to 0.1 parts by weight, and from the viewpoint of further improving the meat-like properties (particularly, adhesiveness) in the meat-like processed food, it may be, for example, preferably 0.0001 to 0.07 parts by weight, more preferably 0.0003 to 0.04 parts by weight, and even more preferably 0.0005 to 0.02 parts by weight.

Alternatively, in the case where the predetermined compound is a natural product derived from the living organism, the amount of the predetermined compound per 100 parts by weight of the plant protein may be, for example, 0.05 to 100 parts by weight, and preferably 0.5 to 70 parts by weight, based on the dry weight of the living organism as a raw material, from the viewpoint of further improving the crosslinkability of the plant protein. In the case where the production method of the present invention is used for producing a meat-like processed food using a textured vegetable protein material, the amount of the above-mentioned predetermined compound per 100 parts by weight of the textured vegetable protein material (material obtained by swelling with water) is, for example, 0.01 to 10 parts by weight, and from the viewpoint of further improving the meat-like properties (particularly, adhesiveness) in the meat-like processed food, it is preferably 0.1 to 7 parts by weight, more preferably 0.3 to 4 parts by weight, and even more preferably 0.5 to 2 parts by weight, in terms of the dry weight of the organism to be used as a raw material.

The amount of the above-mentioned predetermined compound used is, for example, 0.0001 to 0.1 part by weight, preferably 0.001 to 0.01 part by weight, more preferably 0.003 to 0.007 part by weight, per 1 part by weight of the polysaccharide. In the case where the predetermined compound is a natural product derived from the living organism, the amount of the predetermined compound used is, for example, 0.01 to 10 parts by weight, preferably 0.1 to 1 part by weight, and more preferably 0.3 to 0.7 part by weight, based on 1 part by weight of the polysaccharide, as a dry weight conversion amount of the living organism to be a raw material.

1-5 reaction operations and conditions

In the step of allowing polysaccharides and a copper-rich oxidase (a compound which is further defined as the case may be) to act on a plant protein, a plant protein mixture containing a plant protein material, polysaccharides and a copper-rich oxidase, and a compound which is further defined as the case may be, in water is appropriately prepared, and a reaction for improving the crosslinking property is performed.

In the case where the production method of the present invention is used for producing a meat-like processed food using a textured vegetable protein material, a mixture comprising a textured vegetable protein material in a state swollen with water, a polysaccharide and a copper-rich oxidase, and, if necessary, a compound is prepared, and a reaction for improving meat-like properties of livestock based on crosslinkability is performed.

In the case of containing the textured vegetable protein material, powdery pea protein may be mixed in the mixture to further improve the cohesiveness. The amount of the powdery pea protein used is, for example, 5 to 20 parts by weight, preferably 10 to 13 parts by weight, per 100 parts by weight of the textured vegetable protein material (material swollen with water).

In addition, in the case of containing the textured vegetable protein material, the base material, the connecting material, and/or other food materials may be mixed as necessary. Examples of the base material include water (excluding water impregnated in the swollen textured vegetable protein material) and/or oil. As the connecting material, one or two or more kinds of materials selected from breading, starches, eggs, and the like can be used. As other food materials, those skilled in the art can appropriately determine the type of meat-like processed food, and examples thereof include vegetables. In the case of using water and oil as the base material, the amount of water to be used is preferably 0.5 to 6 parts by weight, more preferably 1 to 4 parts by weight, and even more preferably 1.5 to 2.5 parts by weight, based on 1 part by weight of oil, from the viewpoint of improving water retention property also in liquid retention. In the case of using water and oil as the base material, the amount of the oil to be used is preferably 0.2 to 2 parts by weight, more preferably 0.4 to 1.5 parts by weight, and even more preferably 0.8 to 1.1 parts by weight, based on 1 part by weight of water, from the viewpoint of improving the oil retention property.

The treatment temperature of the mixture may be appropriately determined in consideration of the optimum temperature of the multi-copper oxidase, and examples thereof include 4 to 80℃and preferably 15 to 70 ℃. The treatment time is not particularly limited, and examples thereof include 0.1 to 18 hours, preferably 0.2 to 3 hours. The production method of the present invention can effectively exhibit a crosslinking effect even under the otherwise unfavorable reaction conditions in which the multicopper oxidase alone cannot exhibit the effective crosslinking effect. From such a viewpoint, the treatment temperature of the mixture is preferably 15 to 45 ℃, more preferably 15 to 35 ℃, still more preferably 15 to 30 ℃, still more preferably non-heating (room temperature, preferably 15 to 25 ℃) and the treatment time is preferably 0.5 to 1.5 hours, still more preferably 0.8 to 1.2 hours.

The processed mixture containing the textured vegetable protein material is molded into a shape suitable for a desired form of the meat-like processed food, and the meat-like processed food can be obtained by cooking with heat.

The cooking method can be appropriately determined by those skilled in the art according to the type of meat-like processed food. Specifically, examples of the heating cooking method include boiling, baking (toast), roasting (bak), grilling (grill), baking (broil), steaming, frying, and the like. These heating and cooking methods may be used alone or in combination of 1 or more.

1-6 meat-like processed food

When the production method of the present invention is used for producing a meat-like processed food using a textured vegetable protein material, at least any one of the meat-like properties such as adhesiveness, liquid retention, digestion rate, and yield in processing of the obtained meat-like processed food (alternative meat food) is improved as compared with the case of producing the meat-like processed food without using polysaccharides and/or a multi-copper oxidase.

The specific form of the meat-like processed food is not particularly limited, and may be a meat-like processed food prepared by molding and heating a meat type using minced meat. Specifically, hamburger patties, meatballs, ground meat patties (pads), meat strips, pancakes, and the like can be cited.

2. Cross-linking agent for vegetable protein

Polysaccharides can improve the crosslinkability of plant proteins based on the enzyme polychromatic oxidase. Accordingly, the present invention also provides a crosslinking agent for a vegetable protein comprising polysaccharides and a copper-rich oxidase. From the viewpoint of further improving the crosslinkability, the crosslinking agent of the present invention further preferably contains a compound selected from the group consisting of betaines, anthocyanins, curcumins, polyhydroxy chalcones and polyhydroxy anthraquinones, more preferably contains betaines, further preferably contains betaines, beet extracts and/or beets, and still further preferably contains beets.

Polysaccharides and copper oxidases exhibit excellent plant protein crosslinkability, and therefore, when applied to a textured plant protein material, meat-like processed foods obtained can have improved livestock meat-like characteristics as the crosslinkability of plant proteins increases. Examples of such meat-like properties include adhesiveness, liquid retention, digestion rate, and yield in processing.

Therefore, the crosslinking agent of the present invention can be used as an adhesion improver for meat-like processed foods using a textured vegetable protein material. The cohesiveness of the meat-like processed food using the textured vegetable protein material can be confirmed by quantitatively measuring the hardness at the time of processing into the meat-like processed food. The greater the hardness, the higher the adhesion.

The crosslinking agent of the present invention can improve the adhesiveness of a meat-like processed food using a textured vegetable protein material, and therefore can be used as a taste modifier for a meat-like processed food using a textured vegetable protein material. Specifically, when the thermoreversible gelling agent is used as the polysaccharide, the thermoreversible gelling agent can be effectively used as the taste modifier. In this case, the improvement in the taste of the meat-like processed food using the textured vegetable protein material can be confirmed by: the texture of the textured vegetable protein material is perceived to be similar to the texture of a general processed livestock meat food in comparison with a processed meat-like food in which a thermoreversible gelling agent and/or a multicopper oxidase are not used, and the texture is combined with the elasticity of the food due to the binding.

The crosslinking agent of the present invention can be used as a liquid retention enhancer for meat-like processed foods using a textured vegetable protein material. Liquid retention includes water retention and oil retention. The liquid retention property of the meat-like processed food using the textured vegetable protein material can be confirmed by quantitatively measuring the weight difference before and after centrifugation of the meat-like processed food. The smaller the weight difference, the greater the liquid retention.

The crosslinking agent of the present invention can be used as a digestion rate improver for meat-like processed foods using a textured vegetable protein material. The digestion rate of meat-like processed foods using the textured vegetable protein material can be confirmed by the following means: quantitatively, the meat-like processed food was digested for a predetermined period of time in a simulated stomach environment (in artificial gastric juice, under a temperature condition corresponding to body temperature), and the free amino nitrogen and residue after digestion were measured. The more free amino nitrogen and the less residues after digestion within a prescribed time, the faster the digestion rate.

The crosslinkable agent of the present invention can be used as a yield improver in the production of meat-like processed foods using a textured vegetable protein material. In the case where the cross-linking improving agent of the present invention is used as the yield improving agent, the meat-like processed food is a food obtained by cooking with heat, and preferably a food obtained by baking. The yield in the production of a meat-like processed food using a textured vegetable protein material can be confirmed by quantitatively measuring the weight difference between the meat-like processed food before and after cooking. The smaller the weight difference, the greater the yield.

In the cross-linking improving agent for vegetable protein, the types and amounts of the components used are as shown in column "1. Method for producing cross-linked vegetable protein".

Examples

The present invention will be specifically described with reference to the following examples, but the present invention is not to be construed as being limited to the following examples.

[ use of materials ]

TABLE 1

(※1)Beta vulgaris ssp.vulgaris var.Altissima

(Rg2) contains ferulic acid 0.5-1 wt%

(※3)Beta vulgaris ssp.vulgaris var.Vulgaris

[ laccase Activity value assay ]

The enzymatic activity of laccase was measured by the method described below using 2,2' -diazabis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (manufactured by ABTS, boehringer Mannheim Co.) as a substrate.

ABTS was dissolved in 25mM citrate buffer (pH 3.2) at a concentration of 1.0mg/ml to prepare a base solution. 3.0ml of the base solution was placed in a test tube (cuvette), and after preheating at 25℃0.1ml of enzyme solution was added, stirred, incubated at 25℃and absorbance at 405nm after 1 minute and after 3 minutes was measured. Under this condition, the amount of enzyme that increases absorbance at 405nm by 1.0OD in 1 minute was defined as 1 unit (U).

Test example 1

In 100mM phosphate buffer (pH 7.0), 10mL of a solution in which the materials shown in Table 2 were added in the indicated amounts (wherein the amount of laccase is indicated by the activity value in 10mL of the reaction solution) was prepared, and reacted at 40℃for 60 minutes. After the reaction, the reaction solution was subjected to SDS-PAGE. The degree of crosslinking of the protein can be confirmed by the presence of a band at the origin in SDS-PAGE and the concentration of the band. The results are shown in FIG. 1.

TABLE 2

	Lane 1	Lane 2	Lane 3	Lane 4
					Soybean protein (powder)	10w/w％	10w/w％	-	10w/w％
Pectin	-	-	0.5w/w％	0.5w/w％
					Laccase enzyme	-	100U	100U	100U

As can be seen from FIG. 1, the effective crosslinking reaction was not confirmed by laccase alone (lane 2) and pectin was not crosslinked by laccase (lane 3) under the reaction conditions of about 60 minutes at 40℃but the effective crosslinking reaction was confirmed by combining pectin with laccase (lane 4).

Test example 2: cohesiveness and mouthfeel-granular soy protein ]

To 80g of granular (small granular) soybean protein, warm water (40 ℃ C.) was added in an amount of 5 times by weight, and the mixture was allowed to stand for 10 minutes to swell to a saturated state. Moisture was removed and 25g of swollen granular soy protein was weighed each time. To the weighed granular soybean protein, 2.75g of powdered pea protein (NUTRALYS F85M manufactured by Roquette Co.) and an additive selected from methylcellulose, pectin and laccase were added in amounts shown in Table 3 to prepare a vegetable protein mixture. The amounts shown in Table 3 refer to the amounts blended in the vegetable protein mixture. The vegetable protein mixture is fully mixed and shaped into a hamburger patty, and the hamburger patty is left to stand for 60 minutes at room temperature and then baked, so that the meat-like processed food is obtained.

TABLE 3

In order to evaluate the degree of cohesiveness of the granular soybean protein in the obtained meat-like processed food, the hardness of the meat-like processed food was measured by a rheometer (manufactured by SUN science corporation). The greater the measured value of hardness, the greater the degree of cohesiveness. Note that, in the case of disintegration of the meat-like processed food, the hardness was set to be undetectable (n.d.; non detected). The measurement results of the hardness are shown in FIG. 2. Fig. 3 shows a photograph of the appearance of each meat-like processed food.

As shown in fig. 2 and 3, in the meat-like processed food to which no polysaccharide was added, granular soybean protein was not cohesively disintegrated not only in the case where laccase was not added (comparative example 1) but also in the case where laccase was added (comparative example 2). That is, it was confirmed that laccase itself did not have an effect of binding granular soybean protein. In the case where methylcellulose was added alone (comparative example 3), the adhesiveness of the granular soybean protein was confirmed, but in the case where laccase was used in combination with methylcellulose (example 1), although laccase itself had no adhesive effect (comparative example 2), the adhesiveness of the granular soybean protein was further enhanced. In the case where 2 wt% pectin and 4 wt% pectin were added separately (comparative examples 4 and 5), the granular soybean protein did not bind and disintegrate, but in the case where laccase was used in combination (examples 2 and 3), although laccase itself did not bind (comparative example 2), the binding property of the granular soybean protein was also significantly enhanced.

The taste (tongue touch) of the meat-like processed food having confirmed adhesiveness was evaluated, and as a result, the food was a cooked product when methylcellulose was added (comparative example 3, example 1), and the food was a different taste from a general livestock meat processed food. On the other hand, when pectin and laccase are added (examples 2 and 3), the meat-like granular sensation is obtained, and the granular sensation is combined with the elasticity of the food based on the binding, and the meat-like granular sensation has the same taste as that of a general processed livestock meat food.

Test example 3: cohesiveness and mouthfeel-granular pea protein ]

A meat-like processed food was obtained in the same manner as in test example 2, except that the granular (small granular) soybean protein was changed to the granular (small granular) pea protein. The ingredients used in the production of the meat-like processed food of this test example and the amounts thereof used are shown in table 4 in the same form as table 3.

TABLE 4

The obtained meat-like processed food was subjected to measurement of hardness for evaluation of the degree of cohesiveness, photographing of an appearance photograph, and evaluation of taste, as in test example 2. The measurement results of the hardness are shown in FIG. 4. Fig. 5 shows a photograph of the appearance of each meat-like processed food.

As shown in fig. 4 and 5, in the meat-like processed food to which no polysaccharide was added, granular pea protein did not bind and disintegrate not only in the case where laccase was not added (comparative example 6) but also in the case where laccase was added (comparative example 7). That is, it was confirmed that laccase itself did not bind granular pea proteins. In the case of methyl cellulose alone (comparative example 8), the adhesiveness of granular pea protein was confirmed, but in the case of laccase in combination with methyl cellulose (example 4), although laccase itself had no adhesiveness (comparative example 7), the adhesiveness of granular pea protein was further enhanced. In the case of adding 2 wt% pectin and 4 wt% pectin separately (comparative examples 9, 10), the granular pea proteins did not bind and disintegrate, but in the case of using laccase in combination (examples 5, 6) the binding properties of the granular pea proteins were significantly enhanced although laccase itself did not bind (comparative example 7).

The taste (tongue touch) of the meat-like processed food having confirmed adhesiveness was evaluated, and as a result, the food was a cooked product when methylcellulose was added (comparative example 8, example 4), and the food was a different taste from a general livestock meat processed food. On the other hand, when pectin and laccase are added (examples 5 and 6), the meat-like granular sensation is obtained, and the granular sensation is combined with the elasticity of the food based on the binding, and the meat-like granular sensation has the same taste as that of a general processed livestock meat food.

Test example 4: cohesiveness-granular pea protein ]

5 times the weight of warm water (40 ℃) was added to the granular (small granular) pea protein, and the mixture was allowed to stand for 10 minutes to swell to a saturated state. Moisture was removed and 25g of swollen granular pea protein was weighed each time. For the weighed granular pea proteins, 2.75g of powdery pea proteins were mixed, and additive ingredients selected from beet dry powder as beet pigment source, methylcellulose, pectin and laccase were added in the amounts shown in table 5 to prepare vegetable protein mixtures. The amounts shown in Table 5 refer to the amount incorporated in the vegetable protein mixture (wherein the amount of laccase represents the activity value per 1g of swollen granular pea protein). The vegetable protein mixture is fully mixed and shaped into a hamburger patty, and the hamburger patty is left to stand for 60 minutes at room temperature and then baked, so that the meat-like processed food is obtained.

The hardness of the obtained meat-like processed food was measured in the same manner as in test example 2 to evaluate the degree of cohesiveness. The measurement results of the hardness are shown in Table 5.

TABLE 5

An activity value of () for each 1g of swollen granular pea protein.

As shown in table 5, when methylcellulose, pectin, and laccase were added to the granular pea protein (examples 7 and 9), the adhesiveness of the granular pea protein was improved, and the extent thereof was remarkable when pectin was used (example 9). In addition, when betalains were added (examples 8 and 10), the cohesiveness of the granular pea proteins was further improved.

Test example 5: cohesiveness-tissue-like plant protein Material of various shapes and origins ]

Warm water (40 ℃) was added to the tissue-like vegetable protein materials of various shapes and sources shown in tables 6 to 13 in an amount of 5 times by weight, and the materials were allowed to stand for 10 minutes to swell to a saturated state. Moisture was removed and 25g of the swollen tissue-like vegetable protein material was weighed separately. A vegetable protein mixture was prepared by adding an additive selected from methylcellulose, pectin, and laccase to a weighed amount of a vegetable protein material, together with 5g of water and 5g of olive oil, in the amounts shown in tables 6 to 13. The amounts shown in tables 6 to 13 refer to the amount blended in the vegetable protein mixture (wherein the amount of laccase represents the activity value per 1g of swollen tissue-like vegetable protein material). The amount of methylcellulose or pectin to be blended was 2 parts by weight based on 100 parts by weight of the swollen tissue-like vegetable protein material. The vegetable protein mixture is fully mixed and shaped into a hamburger patty, and the hamburger patty is left to stand for 60 minutes at room temperature and then baked, so that the meat-like processed food is obtained.

The hardness of the obtained meat-like processed food was measured and an external photograph was taken in the same manner as in test example 2 to evaluate the degree of adhesiveness. The measurement results of the hardness are shown in tables 6 to 13. Fig. 6 to 13 show the appearance photographs of each meat-like processed food.

TABLE 6

TABLE 7

TABLE 8

TABLE 9

TABLE 10

TABLE 11

TABLE 12

TABLE 13

As is clear from tables 6 to 13, in the meat-like processed food to which no polysaccharide was added, the tissue-like plant protein material did not bind and disintegrate even when laccase was added as well as when laccase was not added. In the case of methyl cellulose alone, the adhesiveness of the tissue-like plant protein material was confirmed, but in the case of laccase in combination with methyl cellulose, although laccase itself had no adhesiveness, the adhesiveness of the tissue-like plant protein material was further enhanced. In the case of pectin alone, the tissue-like plant protein material does not bind and disintegrate, but in the case of laccase alone, although laccase itself has no binding effect, the binding of the tissue-like plant protein material is significantly enhanced.

Test example 6: yield and liquid retention ]

To the granular (small granular) soybean protein, warm water (40 ℃) was added in an amount of 5 times by weight, and the mixture was allowed to stand for 10 minutes to swell to a saturated state. Moisture was removed and 25g of the swollen granular (small granular) soy protein was weighed each time. To the weighed granular (small granular) soy protein, a vegetable protein mixture was prepared by adding methylcellulose or pectin at a final concentration of 2w/w%, water and olive oil in the amounts shown in table 14, and laccase at 20U relative to 1g of the swollen granular (small granular) soy protein. The vegetable protein mixture was thoroughly mixed and formed into a hamburger patty, allowed to stand at room temperature for 60 minutes (the product obtained at this stage is referred to as "pre-cooking patty"), and then subjected to a baking process to obtain a meat-like processed food ("post-cooking patty").

In order to evaluate the yield, the weight of each of the minced meat cakes before and after cooking was measured, and the cooking loss ratio (%) was calculated based on the following numerical expression. The results are shown in Table 14. The smaller the ratio (%) of cooking loss, the higher the yield.

[ mathematics 1]

Cooking loss (%) = (W1-W2) ×100

W1: weight of minced meat cake before cooking (g)

W2: weight of minced meat cake after cooking (g)

To evaluate the liquid retention, the ground meat cake after firing was separated into 5g, and the supernatant was discarded by centrifugation at 3000rpm to obtain a ground meat cake after centrifugation. The water retention and oil retention (%) were calculated based on the following formulas by measuring the weights of the ground meat cakes before and after centrifugation. The results are shown in Table 14. The larger the water retention and oil retention (%), the higher the liquid retention, and the juicy taste can be obtained.

[ math figure 2]

Water retention/oil retention (%) =100- (w 1-w 2)/w1×100

w1: weight before centrifugation (g)

w2: weight after centrifugation (g)

TABLE 14

The symbol (1) represents a weight ratio (parts by weight) of 100 parts by weight relative to the swollen vegetable protein material.

wp represents parts by weight (weight parts or parts by weight)

((2) represents the Activity value per 1g of swollen vegetable protein Material)

As is clear from table 14, in the ground meat cake produced using pectin and laccase, the cooking loss was reduced, and thus the yield was confirmed to be improved. Further, as is clear from table 14, in the ground meat cake produced using pectin and laccase, the water retention property and the oil retention property are increased, and thus it is confirmed that the liquid retention property is improved.

Test example 7: digestion Rate ]

To the granular (small granular) soybean protein, warm water (40 ℃) was added in an amount of 5 times by weight, and the mixture was allowed to stand for 10 minutes to swell to a saturated state. Moisture was removed and 25g of swollen granular soy protein was weighed each time. To the weighed granular soybean protein, an additive selected from methylcellulose, pectin, and laccase was added in the amounts shown in table 15 to prepare a vegetable protein mixture. The amounts shown in Table 15 refer to the amount blended in the vegetable protein mixture (wherein the amount of laccase represents the activity value per 1g of swollen granular soybean protein). The vegetable protein mixture was thoroughly mixed and formed into a hamburger patty, and left standing at room temperature for 60 minutes and then baked to obtain a meat-like processed food (minced meat patty).

TABLE 15

The weight ratio of ((-1) to 100 parts by weight of the swollen granular soybean protein) is 2 parts by weight.

(. About.2) is the activity value of the swollen granular soybean protein per 1 g.

The minced meat patties were cut to 5g and immersed in simulated gastric fluid (77 mL of purified water, 13mL of Mcilvaine buffer pH5.0, 4.39g of NaCl, 0.22g of KCl, caCl) ₂ 0.04g, final concentration of 0.0065% pepsin) was reacted at 37℃for 80 minutes at 60 rpm. At this time, 1N HCl was added every 10 minutes and the pH was adjusted to 3.0. After the reaction, the reaction mixture was boiled and cooled, and the amount of free amino nitrogen and the amount of residue after digestion were measured. The results are shown in fig. 14 and 15.

As shown in fig. 14, according to the minced meat patties of example 36, the free amino nitrogen amount was increased to 2 times that of comparative example 54, and as shown in fig. 15, the residue amount was half that of comparative example 54. That is, according to the minced meat patties of example 36, the digestion rate was improved, thus suggesting an improvement in the nutrient absorption amount.

Claims (16)

1. A method for producing a crosslinked plant protein, characterized by comprising a step of allowing polysaccharides and a copper-rich oxidase to act on a plant protein.

2. The method according to claim 1, wherein the polysaccharide is a thermoreversible gelling agent.

3. The production method according to claim 1 or 2, wherein the thermoreversible gelling agent is pectin.

4. The method according to any one of claims 1 to 3, wherein in the step, a compound selected from the group consisting of betaines, anthocyans, curcuminoids, polyhydroxy chalcones, and polyhydroxy anthraquinones is further reacted.

5. The method according to any one of claims 1 to 3, wherein the step further comprises a betalain.

6. The method according to any one of claims 1 to 5, wherein the multi-copper oxidase is laccase and/or bilirubin oxidase.

7. The method according to any one of claims 1 to 6, wherein the method comprises a step of allowing the polysaccharide and the multi-copper oxidase to act on a textured vegetable protein material to obtain a meat-like processed food,

the vegetable protein is included in the organized vegetable protein material,

the crosslinked vegetable protein is contained in the meat-like processed food.

8. A cross-linking agent for vegetable proteins, which comprises polysaccharides and a copper-rich oxidase.

9. The crosslinking agent according to claim 8, wherein the crosslinking agent is used as an adhesion improver for meat-like processed foods using a textured vegetable protein material.

10. The crosslinking agent according to claim 8, wherein the crosslinking agent is used as a taste modifier for meat-like processed foods using a textured vegetable protein material.

11. The crosslinking agent according to claim 8, wherein the crosslinking agent is used as a liquid retention enhancer for meat-like processed foods using a textured vegetable protein material.

12. The crosslinking agent according to claim 8, wherein the crosslinking agent is used as a digestion rate enhancer for meat-like processed foods using a textured vegetable protein material.

13. The crosslinking agent according to claim 8, wherein the crosslinking agent is used as a yield-improving agent in the production of meat-like processed foods using a textured vegetable protein material.

14. The adhesion promoter of any one of claims 8 to 13, wherein the adhesion promoter further comprises a compound selected from betaines, anthocyans, curcuminoids, polyhydroxy chalcones and polyhydroxy anthraquinones.

15. The adhesion promoter of any one of claims 8 to 13, wherein the adhesion promoter further comprises a betalain.

16. A meat-like processed food obtained by the production method according to claim 7.