JP2024001643A - Quality maintenance agent for peeled and/or cut vegetables and fruit and quality maintenance method for peeled and/or cut vegetables and fruit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a novel quality maintenance agent which is capable of easily and effectively maintaining quality of peeled and/or cut vegetables and fruit during their storage and which has high safety; and a quality maintenance method for peeled and/or cut vegetables and fruit.

SOLUTION: A quality maintenance agent for peeled and/or cut vegetables and fruit includes α-lipoic acid and L-cystine. A quality maintenance method for peeled and/or cut vegetables and fruit includes treating the peeled and/or cut vegetables and fruit with a solution including α-lipoic acid of 0.025 to 5.0% (w/v) and L-cystine of 0.2 to 5.0% (w/v), with a pH thereof being adjusted to 9 to 12 with a pH adjusting agent.

SELECTED DRAWING: None

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to an agent for preserving the quality of peeled and/or cut vegetables and fruits, and a method for preserving the quality of peeled and/or cut vegetables and fruits.

Conventionally, various studies have been made to prevent quality deterioration during food storage.

For example, as a technology to suppress deterioration such as discoloration over time of fruits and vegetables such as bananas and processed products thereof, ascorbic acids and/or salts thereof, α-lipoic acid and/or complexes thereof, polyphosphates and/or A technique using pyrophosphate has been proposed (see, for example, Patent Document 1).

A technology using α-lipoic acid and L-ascorbic acid or L-ascorbate has been proposed as a technology to prevent deterioration due to discoloration that occurs during storage of peeled or cut fresh vegetables and fruits ( For example, see Patent Document 2).

Techniques such as those proposed above have been effective to some extent in preventing quality deterioration during food storage.

However, in recent years, there has been a serious increase in the amount of food being discarded, and there are also concerns about increased costs for replacing products due to labor shortages at supermarkets, convenience stores, and the like. Therefore, there is an increasing demand for quality preservation agents for peeled and/or cut vegetables and fruits that exhibit better quality preservation effects than conventional ones.

Therefore, a new quality preservation agent that can easily and effectively maintain the quality of peeled and/or cut vegetables and fruits during storage and is also highly safe, and a new quality preservation agent for peeled and/or cut vegetables and fruits. At present, there is a strong need for rapid development of quality maintenance methods.

Japanese Patent Application Publication No. 2021-185756 Japanese Patent Application Publication No. 2007-029071

The present invention aims to meet such demands, break through the current situation, solve the aforementioned problems in the past, and achieve the following objects. That is, the present invention provides a new quality preserving agent that can simply and effectively maintain the quality of peeled and/or cut vegetables and fruits during storage and is also highly safe; The purpose is to provide a method for maintaining the quality of vegetables and fruits.

As a result of intensive studies to achieve the above object, the present inventors have found that by using two ingredients, α-lipoic acid and L-cystine, as active ingredients, various types of peeled and/or cut vegetables can be processed. The quality of fruits during storage can be easily and effectively maintained (discoloration, browning, etc. during storage can be easily and effectively suppressed, and color, freshness, flavor, etc. can be maintained). This discovery led to the completion of the present invention.

The present invention is based on the above findings of the present inventors, and means for solving the above problems are as follows. That is,
<1> A quality preserving agent for peeled and/or cut vegetables and fruits, characterized by containing α-lipoic acid and L-cystine.
<2> The above <1> used as a solution containing 0.025 to 5.0% (w/v) α-lipoic acid and 0.2 to 5.0% (w/v) L-cystine. It is a quality preservation agent described in .
<3> The quality preserving agent according to <1> or <2>, which further contains a pH adjuster and is used as a solution with a pH of 9 to 12.
<4> Quality maintenance according to any one of <1> to <3> above, wherein the mass ratio of α-lipoic acid to L-cystine (α-lipoic acid:L-cystine) is 1 to 25:1 to 200. It is a drug.
<5> The quality preservation agent according to any one of <1> to <4>, which prevents discoloration during storage at -20°C to 30°C.
<6> Contains 0.025 to 5.0% (w/v) α-lipoic acid and 0.2 to 5.0% (w/v) L-cystine, and adjusts the pH to 9 to 12 with a pH adjuster. This is a method for preserving the quality of peeled and/or cut vegetables and fruits, which comprises treating the peeled and/or cut vegetables and fruits using a solution adjusted to .
<7> The method according to <6> above, which uses a solution containing α-lipoic acid and L-cystine at a mass ratio of 1 to 25:1 to 200 (α-lipoic acid: L-cystine).
<8> The method described in <6> or <7> above, which prevents discoloration during storage at -20°C to 30°C.

According to the present invention, the above-mentioned problems in the past can be solved, the above-mentioned object can be achieved, and the quality of peeled and/or cut vegetables and fruits can be easily and effectively maintained during storage, It is possible to provide a new quality preservation agent that is also highly safe and a method for preserving the quality of peeled and/or cut vegetables and fruits.

FIG. 1 is a diagram showing the state of the avocado of Test Example 1. FIG. 2 is a diagram showing the state of the avocado of Test Example 2. FIG. 3 is a diagram showing the state of the avocado of Test Example 3. FIG. 4 is a diagram showing the state of the avocado of Test Example 4. FIG. 5 is a diagram showing the state of the avocado of Test Example 5. FIG. 6 is a diagram showing the state of the avocado of Test Example 6. FIG. 7 is a diagram showing the state of the avocado of Test Example 7. FIG. 8 is a diagram showing the state of lettuce in Test Example 8. FIG. 9 is a diagram showing the state of burdock in Test Example 9. FIG. 10 is a diagram showing the state of apples in Test Example 10.

(Quality preservation agent for peeled and/or cut vegetables and fruits)
The quality preservation agent for peeled and/or cut vegetables and fruits of the present invention (hereinafter sometimes referred to as "quality preservation agent") contains at least α-lipoic acid and L-cystine, and optionally contains α-lipoic acid and L-cystine. It also contains other ingredients.

In the present invention, two ingredients, α-lipoic acid and L-cystine, which have been used as food additives and have a wealth of dietary experience, are used as the active ingredients of a quality preservation agent for peeled and/or cut vegetables and fruits. do.

<α-lipoic acid>
α-lipoic acid, also called thioctic acid, is a sulfur-containing vitamin-like substance that is widely present in the bodies of animals and plants and functions as a coenzyme. It has traditionally been taken as a supplement material, and was approved as a food additive in 2004. Note that α-lipoic acid has high antioxidant power and is characterized by its ability to reduce polyphenols oxidized by polyphenol oxidase. In the present invention, α-lipoic acid also includes its salts. The salt of α-lipoic acid is not particularly limited and can be selected as appropriate, but sodium salt is preferred because of its high solubility in water.

The α-lipoic acid is not particularly limited as long as it is of a grade that can be used in food applications, and can be selected as appropriate.
The α-lipoic acid is commercially available, and commercially available products can be used as appropriate.
The content of α-lipoic acid in the quality preserving agent is not particularly limited and can be appropriately selected depending on the amount used and the like.

<L-cystine>
L-cystine is a type of amino acid, and is characterized by having a structure in which two cysteine molecules are connected by a disulfide bond.

The L-cystine is not particularly limited as long as it is of a grade that can be used for food purposes, and can be selected as appropriate.
The L-cystine is commercially available, and commercially available products can be used as appropriate.
The content of L-cystine in the quality preservation agent is not particularly limited and can be appropriately selected depending on the amount used and the like.

<Other ingredients>
The other components mentioned above are not particularly limited and can be selected as appropriate as long as they do not impair the effects of the present invention. or its salts, condensed phosphates such as sodium bicarbonate, sodium carbonate, potassium carbonate, calcium oxide, pyrophosphate, polyphosphate, metaphosphate, sodium hydroxide, etc.), components that themselves have bacteriostatic action. (Organic acids and their salts such as lactic acid, acetic acid, and citric acid, amino acids such as alanine, ferulic acid, glycerin fatty acid ester, ethanol, lysozyme, mustard extract, starch extract, horseradish extract, tea extract, licorice plant extracts such as oily extracts, yucca extracts, rosemary extracts, etc.), ingredients with pH-adjusting, bacteriostatic, and texture-improving effects (calcium hydroxide, shell calcium, etc.), salts such as table salt, Saccharides (monosaccharides, disaccharides, maltotriose, oligosaccharides, dextrins, sugar alcohols, etc.), protein hydrolysates, peptides, emulsifiers (glycerin fatty acid esters, organic acid monoglycerides, polyglycerin fatty acid esters, propylene glycol fatty acid esters, sorbitan) Fatty acid ester, sucrose fatty acid ester, lecithin, enzyme-treated lecithin, calcium stearoyl lactate, sodium stearoyl lactate, starch sodium octenyl succinate, etc.), polysaccharide thickener (gum arabic, xanthan gum, welan gum, tamarind seed gum, carrageenan, curdlan) , succinoglycan, locust bean gum, tara gum, pectin, alginate, alginate ester, etc.), antioxidants (ascorbic acid, tocopherols, rosemary extract, catechin, tea extract), etc. The other components may be used alone or in combination of two or more.
The quality preservation agent preferably contains a pH adjuster, since it can further enhance the quality preservation effect. Note that the pH adjusting agent also includes a component having a pH adjusting effect.
The other components mentioned above are commercially available, and commercially available products can be used as appropriate.
The content of the other components in the quality preservation agent is not particularly limited and can be appropriately selected depending on the amount used.

<Aspects>
The quality preservation agent is preferably a mixed preparation of the α-lipoic acid and the L-cystine. When formulating the above-mentioned mixed preparation, the preparation may be made with only the above-mentioned α-lipoic acid and the above-mentioned L-cystine, or the above-mentioned other components may be blended as necessary, or an auxiliary agent may be used as a raw material for formulation. It may also be used as a preparation. The auxiliary agent is not particularly limited and can be selected as appropriate, and preferably includes, for example, common salt, polysaccharides (dextrin, etc.), emulsifiers, and the like.
In addition, the said quality preservation agent may use a predetermined amount of each component at the stage of solution preparation instead of making it into the above-mentioned mixed preparation.
The form of the quality preservation agent is not particularly limited and can be selected as appropriate, and examples include solids such as powder and granules, and liquids dissolved in a solvent such as water.

<Use>
The mode of use of the quality preservation agent is not particularly limited and can be selected as appropriate, but a mode of solution containing the above-mentioned components is preferred.

The method of treating the peeled and/or cut vegetables and fruits using the solution is not particularly limited and can be selected as appropriate. For example, the method of treating the peeled and/or cut vegetables and fruits with the solution is Examples include a method of dipping, and a method of spraying or applying the solution to the peeled and/or cut vegetables and fruits. These may be used alone or in combination of two or more.
The quality preserving agent may be added or mixed in solid form such as powder or granules to peeled and/or cut vegetables and fruits.

-amount to use-
The amount of the quality preserving agent to be used is not particularly limited as long as it contains effective amounts of the α-lipoic acid and L-cystine, and can be selected as appropriate.

[α-lipoic acid]
The amount of α-lipoic acid used is not particularly limited and can be appropriately selected depending on the purpose. For example, when treating the peeled and/or cut vegetables and fruits using the solution, there is no particular restriction on the amount of α-lipoic acid used, that is, the content of α-lipoic acid in the solution, Although it can be selected as appropriate, it is preferably 0.025 to 5.0% (w/v), more preferably 0.04 to 2.0% (w/v). If it is within the above-mentioned preferred range, not only will it be possible to maintain quality, but there will be little impact on the taste and flavor of peeled and/or cut vegetables and fruits, and the cost will be kept within a level that meets consumer demand. It is advantageous in that it can be

[L-cystine]
The amount of L-cystine used is not particularly limited and can be appropriately selected depending on the purpose. For example, when treating the peeled and/or cut vegetables and fruits using the solution, the amount of L-cystine used, that is, the content of L-cystine in the solution, is not particularly limited and can be selected as appropriate. However, it is preferably 0.2 to 5.0% (w/v). When it is within the above-mentioned preferred range, it is advantageous in that not only can the action of α-lipoic acid be further enhanced and quality can be maintained, but also the cost can be kept within a range that meets consumer demand.

The mass ratio of the α-lipoic acid and the L-cystine (α-lipoic acid:L-cystine, hereinafter sometimes referred to as “compounding ratio”) is not particularly limited and may be selected as appropriate. However, the ratio is preferably 1 to 25:1 to 200, more preferably 1 to 10:1 to 65. If it is within the above-mentioned preferred range, it is advantageous in that the quality of peeled and/or cut vegetables and fruits is better maintained.

When the peeled and/or cut vegetables and fruits are treated using the solution, the pH of the solution is not particularly limited and can be selected as appropriate, but it may be adjusted to a pH range of 9 to 12. Preferably, the pH is adjusted to a range of 10 to 12. Adjusting the pH to a preferable range is advantageous in that it is more effective in maintaining the quality of peeled and/or cut vegetables and fruits. The pH of the solution can be adjusted using the pH adjuster.
In addition, in this invention, pH refers to pH at 20 degreeC.

-Usage period-
There is no particular restriction on the timing at which the quality preserving agent acts on peeled and/or cut vegetables and fruits, and can be selected as appropriate.
The number of times the quality preserving agent is applied to peeled and/or cut vegetables and fruits is not particularly limited and can be selected as appropriate, and may be once or multiple times. Moreover, the time for acting (processing time) can also be selected as appropriate.

The quality preserving agent may be used alone or together with other formulations such as shelf life improving agents.

The quality preservation agent can be suitably used to prevent discoloration during storage at -20°C to 30°C.

<Peeled and/or cut vegetables and fruits>
The peeled and/or cut vegetables and fruits in the present invention refer to vegetables that have been subjected to at least one of peeling and cutting, or fruits that have been subjected to at least one of peeling and cutting.
The vegetables and fruits whose quality is to be maintained in the present invention are those which are peeled and/or cut and used in various foods. That is, vegetables and fruits that are eaten as they are without being peeled and/or cut are excluded.

The peeled and/or cut vegetables and fruits are not particularly limited and can be appropriately selected depending on the purpose.
For example, examples of foods that have a problem with red discoloration during storage include cut lettuce (cut lettuce, leaf lettuce, cos lettuce, etc.), peeled and/or cut burdock root, peeled and/or cut taro, etc. can be mentioned.
Examples of products for which browning during storage is a problem include peeled and/or cut apples, peeled and/or cut lotus roots, peeled and/or cut sweet potatoes, peeled and/or cut Japanese yam, and peeled and/or cut yam. Examples include cut peaches, peeled and/or cut loquats, peeled and/or cut radish, and the like.
Examples of products where black discoloration during storage is a problem include cut cabbage, cut garland chrysanthemums, cut mushrooms, peeled and/or cut avocados, peeled and/or cut bananas, peeled and/or cut potatoes, and peeled and/or cut potatoes. Examples include peeled and/or cut eggplant, peeled and/or cut pear, and cut Chinese cabbage.
Other examples include peeled and/or cut tomatoes that tend to discolor to red-black or brownish, and peeled and/or cut tomatoes that are prone to blackening or discoloration during storage.
Note that the peeled and/or cut vegetables and fruits are not limited to those exemplified above. Furthermore, the shape and size of the peeled and/or cut vegetables and fruits are not particularly limited and can be appropriately selected.

The quality preserving agent is preferably applied to fresh products or frozen fresh products, but processed products (boiled, baked, flavored, etc.) are also applicable.

(Method for preserving the quality of peeled and/or cut vegetables and fruits)
The method for preserving the quality of peeled and/or cut vegetables and fruits of the present invention (hereinafter sometimes referred to as "quality preservation method") includes at least a processing step, and further includes other steps as necessary.

<Processing process>
The treatment step contains α-lipoic acid at 0.025 to 5.0% (w/v) and L-cystine at 0.2 to 5.0% (w/v) as active ingredients, and a pH adjuster. This is a process of treating peeled and/or cut vegetables and fruits using a solution whose pH has been adjusted to 9 to 12.

The method of the treatment step is not particularly limited and can be selected as appropriate, for example, the method described in the <Use> section of the above-mentioned (quality preservation agent for peeled and/or cut vegetables and fruits) of the present invention. It can be done in the same way as above.

The peeled and/or cut vegetables and fruits are those described in the item <Peeled and/or cut vegetables and fruits> of the above-mentioned (quality preservation agent for peeled and/or cut vegetables and fruits) of the present invention. It is similar to

According to the quality preservation agent and quality preservation method of the present invention, the quality of peeled and/or cut vegetables and fruits during storage can be easily and effectively maintained. In addition, in the present invention, two ingredients, α-lipoic acid and L-cystine, which have a proven track record of use as food additives and have extensive dietary experience, are used as active ingredients for quality preservation agents for peeled and/or cut vegetables and fruits. It is also highly safe because it is used as a

The present invention will be described below with reference to test examples, but the present invention is not limited to these test examples. In the following test examples, sodium salt of α-lipoic acid was used as an example of α-lipoic acid.

(Test example 1)
The following test was conducted using peeled and cut avocados as an example of peeled and/or cut vegetables and fruits.

-Preparation of solution-
A solution was prepared containing each component listed in Table 1 below in the amount listed in Table 1 below. Note that 3N sodium hydroxide was used as a pH adjuster.

- Processing of peeled and/or cut vegetables and fruits -
The peeled and cut avocado was sliced into arbitrary sizes, and the avocado was soaked in the above solution for 10 minutes.
After that, drain the avocado in a colander.
Next, the drained avocado was placed in a storage container and stored at 10°C or 20°C.

-evaluation-
The condition of the avocados 48 hours after the start of storage was visually confirmed, and the quality maintenance effect (discoloration/browning suppression effect) was evaluated. In the evaluation, the higher the quality maintenance effect (lower degree of discoloration/browning), the higher the number of "+" marks, and the more effective the quality maintenance effect (complete discoloration/browning), the more "-" did. The evaluation results are shown in Table 1. Furthermore, FIG. 1 shows the state of the avocados at the start of storage, 24 hours after the start of storage, and 48 hours after the start of storage.

(Test example 2)
The following test was conducted using peeled and cut avocados as an example of peeled and/or cut vegetables and fruits.

-Preparation of solution-
Solutions were prepared containing each component listed in Tables 2-1 to 2-2 below in the amounts listed in Tables 2-1 to 2-2 below. Note that 3N sodium hydroxide was used as a pH adjuster.

- Processing of peeled and/or cut vegetables and fruits -
The peeled and cut avocado was sliced into arbitrary sizes, and the avocado was soaked in the above solution for 10 minutes.
After that, drain the avocado in a colander.
Next, the drained avocado was placed in a storage container and stored at 10°C.

-evaluation-
The condition of the avocados 48 hours after the start of storage was visually confirmed, and the effect of suppressing discoloration and browning was evaluated in the same manner as in Test Example 1. The evaluation results are shown in Tables 2-1 and 2-2. Further, FIG. 2 shows the state of the avocados at the start of storage, 24 hours after the start of storage, and 48 hours after the start of storage.

(Test example 3)
The following test was conducted using peeled and cut avocados as an example of peeled and/or cut vegetables and fruits.

-Preparation of solution-
Solutions were prepared containing each component listed in Tables 3-1 to 3-2 below in the amounts listed in Tables 3-1 to 3-2 below. Note that 3N sodium hydroxide was used as a pH adjuster.

- Processing of peeled and/or cut vegetables and fruits -
The peeled and cut avocado was sliced into arbitrary sizes, and the avocado was soaked in the above solution for 10 minutes.
After that, drain the avocado in a colander.
Next, the drained avocado was placed in a storage container and stored at 10°C.

-evaluation-
The condition of the avocados 48 hours after the start of storage was visually confirmed, and the effect of suppressing discoloration and browning was evaluated in the same manner as in Test Example 1. The evaluation results are shown in Tables 3-1 and 3-2. Further, FIG. 3 shows the state of the avocados at the start of storage and 48 hours after the start of storage.

(Test example 4)
The following test was conducted using peeled and cut avocados as an example of peeled and/or cut vegetables and fruits.

-Preparation of solution-
Solutions were prepared containing each component listed in Tables 4-1 to 4-2 below in the amounts listed in Tables 4-1 to 4-2 below. Note that 3N sodium hydroxide was used as a pH adjuster.

- Processing of peeled and/or cut vegetables and fruits -
The peeled and cut avocado was sliced into arbitrary sizes, and the avocado was soaked in the above solution for 10 minutes.
After that, drain the avocado in a colander.
Next, the drained avocado was placed in a storage container and stored at 10°C.

-evaluation-
The condition of the avocados 72 hours after the start of storage was visually confirmed, and the effect of suppressing discoloration and browning was evaluated in the same manner as in Test Example 1. The evaluation results are shown in Tables 4-1 and 4-2. Further, FIG. 4 shows the state of the avocados at the start of storage, 24 hours after the start of storage, and 72 hours after the start of storage.

(Test example 5)
The following test was conducted using peeled and cut avocados as an example of peeled and/or cut vegetables and fruits.

-Preparation of solution-
A solution was prepared containing each component listed in Table 5 below in the amount listed in Table 5 below. Note that sodium carbonate and calcium oxide were used as pH adjusters.

- Processing of peeled and/or cut vegetables and fruits -
A peeled avocado was cut into dice and the avocado was soaked in the above solution for 10 minutes.
After that, drain the avocado in a colander.
Next, the drained avocado was placed in a storage container and stored at 10°C.

-evaluation-
The condition of the avocados 72 hours after the start of storage was visually confirmed, and the effect of suppressing discoloration and browning was evaluated in the same manner as in Test Example 1. The evaluation results are shown in Table 5. Further, FIG. 5 shows the state of the avocados at the start of storage and 72 hours after the start of storage.

(Test Example 6)
The following test was conducted using peeled and cut avocados as an example of peeled and/or cut vegetables and fruits.

-Preparation of solution-
A solution was prepared containing each component listed in Table 6 below in the amount listed in Table 6 below. Note that sodium carbonate and calcium oxide were used as pH adjusters.

- Processing of peeled and/or cut vegetables and fruits -
A peeled avocado was cut into dice and the avocado was soaked in the above solution for 10 minutes.
After that, drain the avocado in a colander.
Next, the drained avocado was placed in a storage container and stored frozen at -20°C for 10 days.
Thereafter, the frozen sample was transferred to 10°C and stored.

-evaluation-
The frozen avocado was transferred to 10° C., and the condition of the avocado 24 hours later was visually confirmed, and the effect of suppressing discoloration and browning was evaluated in the same manner as in Test Example 1. The evaluation results are shown in Table 6. Further, FIG. 6 shows the state of the avocados at the start of storage (immediately after the frozen avocados were transferred to 10° C.) and 24 hours after the frozen avocados were transferred to 10° C.

(Test Example 7)
The following test was conducted using peeled and cut avocados as an example of peeled and/or cut vegetables and fruits.

-Preparation of solution-
Solutions were prepared containing each component listed in Tables 7-1 to 7-2 below in the amounts listed in Tables 7-1 to 7-2 below. Note that 3N sodium hydroxide was used as a pH adjuster.

- Processing of peeled and/or cut vegetables and fruits -
The peeled and cut avocado was sliced into arbitrary sizes, and the avocado was soaked in the above solution for 10 minutes.
After that, drain the avocado in a colander.
Next, the drained avocado was placed in a storage container and stored at 10°C.

-evaluation-
The condition of the avocados 96 hours after the start of storage was visually confirmed, and the effect of suppressing discoloration and browning was evaluated in the same manner as in Test Example 1. The evaluation results are shown in Tables 7-1 and 7-2. Further, FIG. 7 shows the state of the avocados at the start of storage and 96 hours after the start of storage.

(Test Example 8)
The following test was conducted using cut lettuce as an example of peeled and/or cut vegetables and fruits.

-Preparation of solution-
A solution was prepared containing each component listed in Table 8 below in the amount listed in Table 8 below. Note that 3N sodium hydroxide was used as a pH adjuster.

- Processing of peeled and/or cut vegetables and fruits -
Lettuce leaves were peeled off one by one, washed with running water for 5 minutes, and then immersed in a 200 ppm sodium hypochlorite solution for 10 minutes. Next, the lettuce was drained in a strainer, and then washed with running water for 5 minutes.
The lettuce leaves described above were torn by hand into appropriate sizes, and the lettuce was immersed in the solution described above for 10 minutes.
Then, it was dehydrated using a salad spinner.
Next, the dehydrated lettuce was placed in a storage container and stored at 10°C.

-evaluation-
The condition of the lettuce 72 hours after the start of storage was visually confirmed, and the effect of inhibiting discoloration and browning was evaluated in the same manner as in Test Example 1. The evaluation results are shown in Table 8. Further, FIG. 8 shows the state of the lettuce at the start of storage, 24 hours after the start of storage, 48 hours after the start of storage, and 72 hours after the start of storage.
As shown in FIG. 8, in Test Example 8-1, no browning was observed until 72 hours after the start of storage. On the other hand, in Test Example 8-2, browning was observed at the cut end of the leaves 48 hours after the start of storage, and the browning further progressed 72 hours after the start of storage.

(Test Example 9)
As an example of peeled and/or cut vegetables and fruits, the following test was conducted using peeled and cut burdock root.

-Preparation of solution-
A solution was prepared containing each component listed in Table 9 below in the amount listed in Table 9 below. Note that 3N sodium hydroxide was used as a pH adjuster.

- Processing of peeled and/or cut vegetables and fruits -
After washing the burdock well with water, I chopped it. This burdock was immersed in the above solution for 10 minutes.
After that, drain the burdock in a colander.
Next, the drained burdock was placed in a storage container and stored at 10°C.

-evaluation-
The state of the burdock 72 hours after the start of storage was visually confirmed, and the effect of suppressing discoloration and browning was evaluated in the same manner as in Test Example 1. The evaluation results are shown in Table 9. Further, FIG. 9 shows the state of the burdock at the start of storage, 24 hours after the start of storage, 48 hours after the start of storage, and 72 hours after the start of storage.
As shown in FIG. 9, in Test Example 9-1, browning was suppressed until 48 hours after the start of storage (evaluation: +++), but some browning was observed 72 hours after the start of storage. On the other hand, in Test Example 9-2, browning was observed 24 hours after the start of storage, and 48 hours after the start of storage, the browning progressed to such an extent that the entire product became reddish.

(Test Example 10)
The following test was conducted using peeled and cut apples as an example of peeled and/or cut vegetables and fruits.

-Preparation of solution-
A solution was prepared containing each component listed in Table 10 below in the amount listed in Table 10 below. Note that 3N sodium hydroxide was used as a pH adjuster.

- Processing of peeled and/or cut vegetables and fruits -
Peel the apple and slice it into 5cm-thick wedges. The apples were immersed in the above solution for 10 minutes.
After that, I put the apples in a colander and drained them.
Next, the drained apples were placed in a storage container and stored at 10°C.

-evaluation-
The condition of the apples 72 hours after the start of storage was visually confirmed, and the effect of suppressing discoloration and browning was evaluated in the same manner as in Test Example 1. The evaluation results are shown in Table 10. Furthermore, FIG. 10 shows the state of the apples at the start of storage, 24 hours after the start of storage, 48 hours after the start of storage, and 72 hours after the start of storage.
As shown in FIG. 10, in Test Example 10-2, browning was observed 24 hours after the start of storage.

As described above, according to the present invention, discoloration and browning during storage of peeled and/or cut vegetables and fruits can be suppressed, and color, freshness, flavor, etc. can be maintained, It was confirmed that the quality could be easily and effectively maintained.

Claims (8)

A quality preservation agent for peeled and/or cut vegetables and fruits, characterized by containing α-lipoic acid and L-cystine. The quality according to claim 1, which is used as a solution containing 0.025 to 5.0% (w/v) of α-lipoic acid and 0.2 to 5.0% (w/v) of L-cystine. Retention agent. The quality preservation agent according to claim 1 or 2, which further contains a pH adjuster and is used as a solution with a pH of 9 to 12. The quality preservation agent according to claim 1 or 2, wherein the mass ratio of α-lipoic acid to L-cystine (α-lipoic acid:L-cystine) is 1 to 25:1 to 200. The quality preservation agent according to claim 3, wherein the mass ratio of α-lipoic acid and L-cystine (α-lipoic acid:L-cystine) is 1 to 25:1 to 200. Contains 0.025-5.0% (w/v) α-lipoic acid and 0.2-5.0% (w/v) L-cystine, and is adjusted to pH 9-12 with a pH adjuster. 1. A method for maintaining the quality of peeled and/or cut vegetables and fruits, the method comprising treating the peeled and/or cut vegetables and fruits with a solution obtained by using a liquid containing the peeled and/or cut vegetables and fruits. 7. The method according to claim 6, wherein a solution containing α-lipoic acid and L-cystine at a mass ratio of 1 to 25:1 to 200 (α-lipoic acid:L-cystine) is used. The method according to claim 6 or 7, which prevents discoloration during storage at -20°C to 30°C.