JPH11243853A - Discoloration preventive agent for fruit and vegetable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively obtain the subject discoloration preventive agent exhibiting excellent discoloration preventive effect, while retaining the quality such as flavor of the fruits/vegetables. SOLUTION: This discoloration preventive agent acts as follows: the activity of polyphenol oxidase, an oxidizing enzyme for polyphenols, is depressed by the action of betaine, thereby preventing the oxidation of the polyphenols in fruits/vegetables to effect their discoloration prevention; combinational use of betaine with other substance(s) having polyphenol oxidase activity inhibitory action affords further excellent polyphenol oxidase activity inhibitory effect; furthermore, adjustment of the pH level of fruits/vegetables to < 7, esp. <=4 using ascorbic acid or kojic acid or the like enables the polyphenol oxidase activity to be inhibited more perfectly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an agent for preventing discoloration of fruits and vegetables, in particular, peeled or cut vegetables and fruits, in particular, for preventing discoloration due to polyphenol oxidase activity.

[0002]

2. Description of the Related Art The demand for simplicity in eating habits tends to increase year by year, and in convenience stores and the like, the demand for fresh vegetables such as fresh vegetable salads and cut fruits has been increasing year by year. However,
Fruits and vegetables such as these raw vegetable salads and cut fruits
Not only is it easy to dry and lose freshness, it is easy to discolor,
It is not easy to distribute and display fresh.

[0003] On the other hand, consumers are increasingly interested in the freshness of foods every year, and particularly with regard to fruits and vegetables, the presence or absence of discoloration and the color and luster thereof have become the most important criteria for purchasing.

[0004] Such "discoloration of fruits and vegetables" is considered to occur due to the action of polyphenol oxidase, that is, polyphenols contained in fruits and vegetables react with oxygen by the activity of polyphenol oxidase, and are oxidized and polymerized (Japanese Patent Application Laid-Open No. 7-1995). -289163, JP-A-2-2
34649, JP-A-59-85279, JP-A-2-2-2
No. 34638). Various "discoloration inhibitors" and "methods for preventing discoloration" for the purpose of preventing polyphenol oxidation or inhibiting polyphenol oxidase activity have hitherto been variously disclosed. For example, “a method for preventing discoloration that captures oxygen that causes oxidation by the reduction action of vitamin C and the like” and “a polyphenol oxidase inhibitor obtained by treating a plant extract from which proteins have been removed with ascorbate oxidase” Discoloration inhibitor as an active ingredient (JP-A-2-23463)
No. 8) "," A method for preventing browning in which a starchy coating layer is formed on the surface of a peeled fruit to prevent contact with oxygen in the air and thereby prevent oxidation (Japanese Patent Laid-Open No. 234649/1990) ", or And "A discoloration inhibitor for fruits and vegetables containing a polyphenol oxidase activity inhibitor such as kojic acid, cinnamic acid and benzoic acid" (JP-A-7-289163).

[0005]

However, the conventional "discoloration preventing agent" and "discoloration preventing method" cannot achieve the desired effect of preventing discoloration, increase the cost, or change the quality. And there is a possibility that the flavor may be reduced. Therefore, the present invention provides an agent for preventing discoloration of fruits and vegetables, which exhibits an excellent discoloration preventing effect, can be manufactured at low cost, and does not reduce the quality of flavor and the like.

[0006]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors to solve such problems, the effect of inhibiting the activity of polyphenol oxidase on "betaine" and remarkably suppressing discoloration of fruits and vegetables such as vegetables and fruits. The present invention has been found based on this. The present invention is based on the idea of preventing discoloration by capturing oxygen which is the cause of oxidation.
This is also different from the idea disclosed in JP 3602 in that betaine is provided to secure the water content of the plant body and thereby maintain the freshness of the plant body.
An object of the present invention is to reduce the activity of polyphenol oxidase, which is an oxidase of polyphenols, by the action of betaine, thereby preventing the oxidation of polyphenols in fruits and vegetables and preventing discoloration of the fruits and vegetables. For this reason, if another substance having an activity of inhibiting polyphenol oxidase activity is used together with betaine, a more excellent effect of inhibiting polyphenol oxidase activity can be obtained.

That is, the discoloration inhibitor for fruits and vegetables according to the present invention is characterized in that betaine is used as an active ingredient for inhibiting the activity of polyphenol oxidase, and is also a substance having an inhibitory activity on betaine and other polyphenol oxidase activities. And (iii) as an active ingredient having a polyphenol oxidase activity inhibitory action. In the present invention, "discoloration of fruits and vegetables" means discoloration due to the action of polyphenol oxidase,
It does not include discoloration caused by freezing or passing through boiling water.

In the present invention, "other substances having an activity of inhibiting polyphenol oxidase activity" are described in
No. 289163, namely kojic acid, cinnamic acid, ferulic acid, benzoic acid, ascorbic acid, vanillic acid, protocatechuic acid, citric acid, coumaric acid, disodium EDTA, eugenol, curcumin, cysteine, glutathione, urocanic acid , Histidine, L-phenylalanine, lysine, glycine, sodium chloride, potassium chloride, cytidine, uridine, adenosine, guanine, guanosine, cytosine, thymidine, uracil, α-rutin, D-glucosamine, N-acetylglucosamine, hesperetin, phytic acid , Sodium pyrosulfite, hyposulfite, sulfurous acid, gallic acid, pyrogallol, pyrocatechol, butylhydroxytoluene, adipic acid, ethanol, catechin, polygodial, proanthocyani , Lemon juice, vanilla extract, dried egg white, sodium caseinate, whey protein, rosemary extract, allyl isothiocyanate, polylysine, their sodium salts, at least one substance selected from the group consisting of these potassium salts, etc. Can be mentioned. Among them, kojic acid and ascorbic acid are more preferred because they can obtain particularly excellent synergistic effects.

Also, ethyl alcohol having antibacterial properties,
If sodium hypochlorite (antiformin) or the like is mixed, an antibacterial effect as well as a discoloration preventing effect can be obtained. By mixing water that has been treated, such as a known freshness preserving agent, anti-tarnish agent, activated water, functional water, or magnetic water or ozone water, the anti-tarnish effect as well as the antibacterial effect and other various effects can be obtained. Thus, a more excellent discoloration inhibitor can be obtained.

[0010] The "vegetables" which are the object of the present invention include:
Cabbage, lettuce, onion, carrot, yam, burdock,
Vegetables such as eggplants and potatoes, apples, bananas, peaches,
Fruits such as pear and peeled or cut fruits thereof can be mentioned.

In the present invention, “betaine” is
All compounds that form zwitterions with internal salts such as quaternary ammonium bases, phosphonium bases and sulfonium bases are meant. Among them, N-trialkyl-substituted amino acids,

[0012]

Embedded image

The compound represented by the formula (wherein R represents an alkyl group having 1 to 8 carbon atoms or H) is a natural product widely present in the animal and plant kingdoms, and is easily decomposed in nature, for example, in the ground or in water. Moreover, it is preferable because there is no concern about environmental pollution.

[0014] Among them, "glycine betaine"
That is, the general formula

[0015]

Embedded image

Is preferred. "Glycinebetaine" is found in shellfish such as seaweed, shrimp and crab, marine products such as squid, octopus, and shellfish, malt, and mushrooms, and is contained in large amounts in molasses of sugar beet. It can be industrially separated and manufactured, is easily available, and its safety has been confirmed as described in the “List of Existing Additives” specified by the Ministry of Health and Welfare as a seasoning. Furthermore, since the solubility in water and alcohol is high, the concentration of the solution can be freely adjusted and the handling is easy. That is, “betaine” in the present invention may be an anhydride or a hydrate, but purified glycine betaine that satisfies the criteria for food additives is most preferred. In addition, the origin of betaine is not particularly limited. For example, any of betaine purified by chemical synthesis, betaine contained in natural products, and betaine extracted from natural products can be used.
As the betaine contained in a natural product, for example, a sugar beet or the like that has been shredded using a grater or a food processor can be used.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION "Anti-tarnishing agent for fruits and vegetables" of the present invention
Is preferably 0.0001 to 60%, more preferably 0.1 to 30%. Within this concentration range, it is more preferable to determine the concentration by appropriately changing the type of vegetables and fruits to be applied, as well as the quality, harvest time, size, weight, and the like.

The discoloration inhibitor for fruits and vegetables of the present invention is adjusted to a pH range where the activity of polyphenol oxidase is remarkably reduced (this pH range varies depending on the type of vegetables and fruits to be treated, but is generally in an acidic range). It is preferable to use them. By adjusting the pH to this range, the effect of inhibiting betaine polyphenol oxidase activity, that is, the effect of preventing discoloration, can be further enhanced. In particular, if the pH is adjusted to an acidic range, particularly 4 or less by using, for example, ascorbic acid or kojic acid, the polyphenol oxidase activity can be more completely suppressed.

In the present invention, the above-mentioned betaine or a mixture thereof can be used directly as it is, but it is generally preferable to use it after dissolving or dispersing it in a suitable liquid carrier such as an aqueous solution. Further, it is mixed with or adsorbed on a suitable powder carrier, and if necessary, an emulsifier, a dispersant, a suspending agent, a penetrant, a wetting agent, a stabilizer, etc. are added thereto, and an aqueous solution, Formulations such as oils, wettable powders, and powders can also be made.

(Method of Use) The discoloration inhibitor of the present invention is dissolved in a suitable liquid carrier as described above to prepare a solution, which is used as the outer surface of the fruit or vegetable, the outer surface of the peeled fruit or the cut face of the cut fruit or vegetable. To apply or spray (including spraying), soak fruits and vegetables in the solution, impregnate the non-woven fabric, package the fruits and vegetables with this non-woven fabric,
Alternatively, it can be used (processed) by directly injecting it into fruits and vegetables. Among them, spraying or dipping is preferred from the viewpoints of efficiency and maintenance of commercial value. Further, the discoloration inhibitor of the present invention exhibits more excellent effects in an environment where the temperature during treatment or storage is reduced to 10 ° C. or lower, particularly 4 ° C. or lower. This is thought to be because the activity of polyphenol oxidase was significantly reduced. Therefore, the temperature of the treatment solution, and preferably also the temperature of the fruits and vegetables, is reduced by 10
It is preferable that the processed fruits and vegetables are adjusted to a temperature of not higher than 10 ° C., and the processed fruits and vegetables are preferably dehydrated, vacuum-packaged and stored at a low temperature of 10 ° C. or lower.

Example 1 In this example, the effect of glycine betaine on browning prevention of cabbage, one of the most commonly distributed vegetables as cut vegetables, was tested.

Shred the cabbage and start with 200 pp
m of antiformin for 5 minutes. This treatment was performed in order to sterilize with antiformin and unify the conditions of the number of bacteria in the test section. After the cabbage thus pretreated is sufficiently dehydrated, it is immersed in glycine betaine aqueous solution of various concentrations (pH) for 5 minutes, and then dehydrated again, put in a vinyl bag appropriately provided with a vent hole, and placed at 10 ° C. It was stored and observed over time. In addition, as a control, one subjected to only antiformin treatment, and as a comparative control, one subjected to the same treatment using sodium ascorbate, which is known to have a browning preventing effect, were prepared. It was stored and observed over time. The results of the above observation are shown in Table 1 below.

In the above observation, the appearance of the cabbage was observed with the naked eye, and the odor was confirmed by smell.
The evaluation was based on the grade criteria. A: No change B: Some water is coming out. In addition to the state of C ... B, further browning is observed. In addition to the state of D... C, browning is further observed as a whole. In addition to the state of E... D, the state further becomes water-immersed, and an off-flavor is also observed.

[0024]

[Table 1]

As a result, the control browned with each passing day and the appearance was remarkably deteriorated, and after 4 days, an unpleasant odor was already observed. On the other hand, in the glycine betaine treatment group, no browning was observed even after 4 days,
In addition, the condition was kept almost unchanged from the day of the treatment. Moreover, the effect of glycine betaine to prevent browning is
It was superior to the effect of sodium ascorbate, which was already used as a browning inhibitor. Than this,
It is considered that the browning inhibitor of the present invention has extremely high practicality.

Claims (3)

[Claims] 1. A discoloration inhibitor for fruits and vegetables, comprising betaine as an active ingredient for inhibiting the activity of polyphenol oxidase activity. 2. Betaine and kojic acid, cinnamic acid, ferulic acid, benzoic acid, ascorbic acid, vanillic acid, protocatechuic acid, citric acid, coumaric acid, disodium EDTA, eugenol, curcumin, cysteine, glutathione, urocanic acid, Histidine, L-phenylalanine, lysine, glycine, sodium chloride, potassium chloride, cytidine, uridine, adenosine, guanine, guanosine, cytosine, thymidine, uracil, α-rutin, D-glucosamine, N-acetylglucosamine, hesperetin, phytic acid, Sodium pyrosulfite, hyposulfite, sulfurous acid, gallic acid, pyrogallol, pyrocatechol, butylhydroxytoluene, adipic acid, ethanol, catechin, polygodial, proanthocyanidin, lemon juice, vanilla Kiss, dried egg white, sodium caseinate, whey protein, rosemary extract, allyl isothiocyanate, polylysine, these sodium salts, at least one substance selected from the group consisting of these potassium salts, and inhibiting the activity of polyphenol oxidase An anti-tarnish agent for fruits and vegetables as an active ingredient of the action. 3. The discoloration inhibitor for fruits and vegetables according to claim 1, wherein the pH of the discoloration inhibitor is adjusted to an acidic range.