JP2000116319A - Preservation of freshness of plant body and freshness preserving agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for preserving freshness of a green plant body especially containing chlorophyll and to obtain a freshness preserving agent and a plant body excellent in a freshness preserving effect. SOLUTION: A plant body is treated with a >=10 wt.% sugar solution and a sugar content of the treated plant body is increased by >=0.4 wt.% based on that of the plant body before treatment and a rhizome of the plant body is contacted with a 10-30 wt.% sugar solution for 10 minutes to 24 hours to preserve the freshness of the plant body. The freshness preserving agent for the plant contains 10-30 wt.% trehalose and/or sucrose. The plant body provided with a high freshness preserving effect has a sugar content in the plant body increased by >=0.4 wt.% based on that of a natural plant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for maintaining freshness of a plant, a freshness maintaining agent, and a plant provided with a high freshness maintaining effect.
In particular, a method for maintaining the freshness of a plant and a freshness preserving agent effective for maintaining a good green color tone of a green plant containing chlorophyll, and the sugar content in the plant in a predetermined amount or more relative to a natural plant The present invention relates to a plant having an increased freshness preserving effect.

[0002]

2. Description of the Related Art Various methods for maintaining the freshness of a plant and a freshness preserving agent comprising a specific component have been proposed, mainly focusing on a method for maintaining freshness of cut flowers, a method for maintaining freshness of cut vegetables and fruits, and the like. . To give some typical examples, for example, a method of immersing a cut portion of a plant in a trehalose-containing aqueous solution is described in JP-A-9-216806.
These are known from JP-A-9-315907 and JP-A-6-227904. Of these, Japanese Patent Application Laid-Open Nos. 9-216806 and 9-315907 propose gluco-oligosaccharides containing trehalose or crop nutritional supplements containing oligosaccharides as components, and the nutritional supplements are hydroponic. It is used in cultivation by adding it to a liquid fertilizer to act.
The nutritional supplement is a gluco-oligosaccharide or oligosaccharide at a concentration of 10% or less, preferably 0.0001 to 3.0%.
The duration of action is not specifically defined, and the examples seek a method of watering every 10 days. Also, the latter JP-A-6-227904 describes that
The present invention proposes a freshness preserving agent for cut flowers and leafy vegetables containing trehalose as an active ingredient. The content of trehalose is 0.001 to 3%. It only states that the leafy vegetables were immersed for 5 minutes.

In addition, for example, an aqueous solution containing 0.8 to 1.5% by weight of ethyl alcohol, 0.1 to 5% by weight of trehalose, and 0.005 to 0.3% by weight of vitamin Cs In addition, a method for maintaining the freshness of cut vegetables in which vegetables cut into appropriate sizes are brought into contact (JP-A-9-2245)
No. 65) 20 to 62% by weight of ethyl alcohol;
2.5 to 20% by weight of trehalose, 0.1 to 0.5
% Of vitamin Cs and the balance of substantially water, which is diluted with water and used for cutting vegetables, freshness preserving agent for cut fruits (JP-A-9-252719), and spraying on plants such as grass and tea. Trehalose powder or a liquid obtained by diluting trehalose at a specified magnification (400 to 500 times) (Japanese Unexamined Patent Application Publication No.
No. -25209), a freshness preserving agent for cut flowers having a trehalose content of 1 to 10% by weight and an ethanol content of 1 to 10% by weight (Japanese Patent Application Laid-Open No. Hei 10-81601). . However, these are characterized in that trehalose is used in combination with ethyl alcohol, vitamins, or the like, or trehalose is used after being diluted at a considerably low concentration. There is no disclosure of an example in which an excellent effect of maintaining the freshness of a plant was obtained by using a sugar solution such as sugar at a high concentration and basically alone.

[0004]

Under such circumstances, the present inventors have considered in view of the above-mentioned prior art that the green color tone of a green plant containing chlorophyll, which has a more excellent freshness preserving effect, is particularly excellent. As a result of intensive studies with the aim of developing a new plant freshness preserving method and a freshness preserving agent capable of maintaining the plant in good and stable condition, the plant was concentrated to 10% by weight (hereinafter abbreviated as%). Treatment with the above sugar solution to increase the sugar content in the plant body after the treatment by 0.4% or more with respect to that before the treatment, so that the rhizome of the plant body is It has been found that the intended purpose can be achieved by bringing a trehalose and / or sucrose sugar solution having a concentration of 10 to 30% into contact with the sugar solution for a predetermined period of time, and further studies have been made, thereby completing the present invention. The present invention
A method for preserving the freshness of a new plant, which has an excellent effect of preserving the freshness, particularly the preservation effect of the green color of a green plant containing chlorophyll, a freshness preserving agent, and a plant having a high preservation effect. It is intended to provide. Another object of the present invention is to provide a new method for maintaining the freshness of a plant body and a freshness preserving agent capable of maintaining the freshness of the plant body satisfactorily and stably by a simple processing operation.

[0005]

The present invention for solving the above-mentioned problems comprises the following technical means. (1) A plant is treated with a sugar solution having a concentration of 10% by weight or more, and the sugar content in the plant after the treatment is 0.1% of that before the treatment.
A method for maintaining freshness of a plant, comprising increasing the amount by 4% by weight or more. (2) A method for maintaining plant freshness, which comprises contacting a rhizome of a plant with a sugar solution having a concentration of 10 to 30% by weight for 10 minutes to 24 hours. (3) The method according to (1) or (2), wherein the sugar solution is an aqueous solution of trehalose and / or sucrose. (4) The above-mentioned (1), wherein the plant is treated with a sugar solution at 0 to 10 ° C.
The method for maintaining freshness of a plant according to any one of (1) to (3). (5) The method for maintaining freshness of a plant according to any one of (1) to (4), wherein the plant is a green one containing chlorophyll. (6) When hydroponically cultivating a plant, the cultivation water is replaced with a sugar solution before harvesting, the sugar solution is brought into contact with the root of the plant, and then the harvest is performed. ) Or (2). (7) A plant freshness preserving agent comprising 10 to 30% by weight of trehalose and / or sucrose. (8) The sugar content in the plant is 0.4
A plant having a high freshness preserving effect, wherein the plant is increased in weight percent or more. (9) In the method of treating a plant body with a predetermined sugar solution to maintain its freshness, the volume and sugar content of the sugar solution before and after the treatment (Bri)
x) is used as an index, the sugar content in the plant after treatment is calculated based on the index, and the sugar content (absorbed sugar content) in the plant after treatment is measured and managed. Method for measuring and controlling sugar content

[0006]

Next, the present invention will be described in more detail. The present invention relates to a method of maintaining a freshness of a plant by treating the plant with a sugar solution having a concentration of 10% by weight or more, wherein the sugar content in the plant after the treatment is 0.4 wt. % Or more, in particular, maintaining the freshness of the plant by bringing the rhizome of the plant into contact with a sugar solution having a concentration of 10 to 30% by weight for 10 minutes to 24 hours. At the same time, a plant in which the sugar content in the plant is increased by 0.4% by weight or more with respect to a natural plant by using the above-mentioned method or the like is provided with a high freshness retaining effect and an excellent freshness retaining effect. Becomes In general, the sugar content of the plant, for example, even if the same kind of plant, its cultivation method,
According to the present invention, the plant is treated with a specific sugar solution, and the sugar content in the plant is set to 0. By increasing the amount by 4% by weight or more, a high freshness retaining effect can be imparted to the plant after harvesting / collecting. In the present invention, it is important that the plant is treated with a sugar solution having a concentration of 10% by weight or more, and the sugar content in the plant after the treatment is increased by 0.4% by weight or more with respect to that before the treatment. Here, as the saccharide used for the sugar solution, those generally called oligosaccharides, for example, sucrose (sucrose), glucose (glucose), fructose (fructose) and the like can be suitably used. And any other oligosaccharides or those having the same effect can be used. Among the oligosaccharides, disaccharides, particularly trehalose, are preferred, and other than trehalose, sucrose is preferred. In particular, trehalose is extremely effective for cruciferous plants such as broccoli, cauliflower, and cabbage, or head vegetables such as cabbage and lettuce. When used at a predetermined concentration, trehalose exhibits a high freshness retaining effect. Trehalose is a type of non-reducing disaccharide in which two molecules of D-glucose are bonded via a reducing group, is a water-soluble stable substance, has three types of isomers, and has a crystalline form: There are dihydrate crystals and anhydrate crystals, which are approved for use in foods. In the present invention, these trehaloses can be used regardless of their types. In the present invention, a concentration of 10
A 30% sugar solution, particularly an aqueous solution of trehalose and / or sucrose, is preferably used.

[0007] The present invention relates to a plant having a rhizome,
Although it can be applied to any plant, it is desirable that the plant be green containing chlorophyll, especially broccoli, cabbage, Chinese cabbage, bok choy, cayare,
Brassicaceae plants such as cauliflower and komatsuna, Asteraceae plants such as lettuce and chrysanthemum, Aceraceae plants such as parsley, honeybee, celery, and fennel; Azaleaceaceous plants such as spinach; Lamiaceae plants such as basil, mint and blue perilla,
It can be suitably applied to solanaceous plants such as peppers and bell peppers.

Next, in the present invention, preferably, the rhizome of the plant is kept in contact with a sugar solution having a concentration of 10 to 30% for 10 minutes to 24 hours to maintain the freshness of the plant. Will be described. (Preparation of sugar solution) Using the above saccharide, first, a concentration of 10 to 3
0%, preferably 10-20%, more preferably 12-
Prepare a 20% sugar solution. Specifically, the saccharide may be dissolved in ordinary water to have the above concentration. In this case, if the concentration is less than 10%, a sufficient freshness maintaining effect may not be obtained. If the concentration is more than 30%, cells in a portion of the plant that has come into contact with the sugar solution may be damaged. , Which can cause discoloration,
It is not preferable because problems such as difficulty in uniformly absorbing sugars throughout the plant, and dehydration and shrinkage of cells in the cut portion of the plant are likely to occur. In addition, in the sugar solution, as long as the above sugar concentration is achieved, a liquid fertilizer such as a mineral active solution or a bactericide such as chitosan, an antioxidant such as ascorbic acid,
An enzyme inhibitor that promotes browning of the tissue may be added. For example, adding antiformin, chitosan, catechin, ascorbic acid, citric acid, succinic acid, tartaric acid, ethyl alcohol, hinokitiol, minerals, calcium salts, benzalkonium chloride, etc. to a sugar solution can maintain freshness (inhibit bacterial growth) ) Is preferred. Among the above sugar solutions, a sugar solution containing trehalose and / or sucrose in an amount of 10 to 30% or the above-mentioned preferred range can be a very effective freshness preserving agent for plants.

(Method of Contacting with Sugar Solution) Next, the plant is treated with a sugar solution having a concentration of 10% or more, and the sugar content in the plant after the treatment is 0.4% of that before the treatment. As described above, the rhizome of the plant is brought into contact with a sugar solution having a specific concentration for a certain period of time, preferably in order to increase by 0.4 to 1.0%. For broccoli, cauliflower, asparagus, etc., the stem containing the edible portion may be cut from the root, and the cut portion may be immersed in a sugar solution. By treating a plant that has been appropriately harvested and placing it on the market as described above, a long-term freshness retaining effect can be achieved in the market. In the case of cut flowers, similarly, after harvesting, the cut portion of the stem may be brought into contact with the sugar solution and then put on the market. Even if cut vegetables such as cut vegetables are brought into contact with a sugar solution, the desired freshness retaining effect cannot be obtained, and the present invention is essentially different from these freshness retaining methods. . In the present invention, the expression that the sugar content in a plant increases by 0.4% or more means, for example, that the plant 1 before the treatment
It means that the content of sugar is increased by 0.4 g or more per 00 g. When a plant is immersed in a sugar solution, the volume and sugar content (Brix) of the sugar solution before and after the immersion are used as indices, and calculated using the indices. Should be within the range. In this case, specifically, in the method of treating a plant with a predetermined sugar solution to maintain its freshness, the volume and sugar content of the sugar solution before and after the treatment (Bri)
Using x) as an index, a method of calculating the sugar content in the plant after treatment based on the index and managing the sugar content (absorbed sugar content) in the plant after treatment is exemplified as a suitable method. You.

[0010] Apart from the above method, in soil cultivation and hydroponic cultivation, the sugar cultivation soil is impregnated with sugar solution or the cultivation water is replaced with sugar solution before harvesting. The sugar solution may be absorbed from the roots of the plant. The above process
The treatment is preferably performed immediately before the harvest, but may be separately performed after the harvest. Particularly, in hydroponic cultivation, the freshness preserving effect is favorably achieved, which is preferable.

(Contact time / contact temperature)
The sugar solution is contacted for 10 minutes to 24 hours, preferably 1 to 6 hours. In this case, if the contact time is less than 10 minutes, a sufficient freshness retaining effect may not be obtained, and if it exceeds 24 hours, the freshness retaining effect does not change, but the contact treatment damages the plant. Is not preferred.

As a rough guide of the contact time depending on the type of plant, broccoli, asparagus, cauliflower and cabbage are 6 to 12 hours, spinach,
Komatsuna, Chingensai, Sirona, Basil, Kaiware,
For leek, shungiku and honey, it takes 1 to 6 hours. As for the temperature condition, the plant is preferably brought into contact with the sugar solution at 0 to 25 ° C, preferably 0 to 10 ° C. As a result, the absorbability of the sugar solution of the plant is further improved, so that the above-mentioned temperature is a preferable condition. Here, a description will be given of the normal freshness retention days of vegetables. Vegetables have different storage periods depending on varieties and cultivation periods. In particular, the early life tends to have a poor shelf life, and the late life tends to have a long shelf life. Therefore, the usual freshness retention days of vegetables are, for example, as follows in the case of asparagus, broccoli, and spinach. Note that this is mainly based on the standard pattern.

(Asparagus) Storage temperature Freshness retention days 1 ° C. 10-20 days 5 ° C. 10-15 days 10 ° C. 3-5 days 20 ° C. 1-2 days (broccoli) Storage temperature Freshness retention days 0 ° C. 20-30 days 5 ° C 7-10 days 15 ° C 3 days (spinach) 3-5 days in a refrigerator (5 ° C) (Refer to Common Vegetable Horticultural Encyclopedia 15 Advanced Technology / Advanced Technology (Agriculture, Mountain and Fishing Village Cultural Association)) As shown, by the method of the present invention,
It can be seen that the freshness of the plant body is better and stably maintained, and the storage period is significantly longer than the normal freshness retention days described above.

[0014]

EXAMPLES Next, the present invention will be specifically described based on examples, but the following examples show preferred examples of the present invention, and the present invention is not limited by the examples. Not something. Example 1 In this example, stems with a flower of broccoli are cut and harvested, and are not subjected to immersion treatment (no treatment), or the cut portions are shown in Tables 1 to 3 and FIGS. After immersion treatment for 6 hours in the treatment solution under the conditions, the freshness retention effect after storage at 10 ° C. for 16 days was examined.

(1) Method 1) Method for measuring chlorophyll The content of chlorophyll was measured as follows. Measurement site Broccoli bud Extraction Extraction with 80% ethanol Measurement 649 nm, 665 n by spectrophotometer
The absorbance at a wavelength of m was measured and the following formula was used: chlorophyll concentration (μg / ml) = 6.10 × (665)
The chlorophyll content of the extract was calculated by (absorbance at nm) + 20.04 × (absorbance at 649 nm) (Mckinn).
eye method). The chlorophyll content per gram is a value obtained by multiplying the above concentration by the amount of the liquid and dividing by the measured plant weight as follows. Chlorophyll (μg / g) = ｛6.10 × (665 nm
Absorbance) + 20.04 × (absorbance at 649 nm)｝ ×
Liquid volume / weight

2) Evaluation method of the result The chlorophyll content (μg / g) immediately after harvesting is 47
6.4. If the value is lower than 6.4, the next evaluation is performed. Residual rate of 80% or more: good green retention, no significant difference with the one immediately after harvesting, with no visual difference / freshness without flower drop Residual rate is less than 80% (particularly lower than about 70%)
Poor green retention, yellowish to the naked eye / Flowers fall tattered and not fresh

(2) Results The results of measuring the chlorophyll content of broccoli by the above method are shown in Table 1 and FIGS. 1 and 2, the weight change immediately after immersion is shown in Table 2, and the absorbed sugar content (increase) is shown in Table 3. Are shown below. Trehalose 10% or more and sucrose 10% or more 1
A chlorophyll retention of 80% or more was obtained over 0 days or more. Weight change is greatest at 6 hours of immersion.
The absorbed sugar content is calculated from the volume of the sugar solution before and after immersion and Brix, and increases in proportion to the increase in weight, and reaches a maximum after 6 hours of immersion. In particular, both trehalose and sucrose were immersed in a sugar solution having a concentration of 10 to 30% for 6 hours.
An increase in sugar of 0.4% or more was obtained, which showed a high residual ratio of chlorophyll.

[0018]

[Table 1]

[0019]

[Table 2]

[0020]

[Table 3]

Example 2 In this example, asparagus seedlings were cut from the root and harvested, and were not subjected to immersion treatment (no treatment), or the cut portions were treated with a treatment solution under the conditions shown in Table 4. After immersion treatment for 6 hours, the freshness retention effect after storage at 10 ° C. for 11 days was examined.

(1) Method 1) Measuring method of chlorophyll The chlorophyll content was measured by the same method as in Example 1 and the tip, center, and lower part (root part) of asparagus were 1 cm thick. Was measured for each of the slices.

2) Method of evaluating the results When the value of the content (μg / g) of chlorophyll decreases in each part, the following evaluation is performed. Residual rate is 80% or more: good green retention, no significant difference between freshly harvested and the naked eye / fresh state Residual rate is less than 80% (particularly lower than about 70%) ...
Poor green retention, yellowish to the naked eye / no freshness

(2) Results The results measured by the above method are shown in Table 4. In each case, a residual ratio of about 80% or more was obtained with 10% or more of trehalose and 10% or more of sucrose.

[0025]

[Table 4]

Example 3 In this example, spinach leaf stems were cut from the roots and harvested, and were not immersed (no treatment), or the cut portions were treated under the conditions shown in Table 5 and FIG. The solution was immersed in the solution for 6 hours, and the freshness retention effect after storage at 10 ° C. for 16 days was examined.

(1) Method 1) Measuring method of color difference Measurement site The central part of a specific leaf of spinach was measured at 10 points and brought into contact with a photometric part of a color difference meter. The difference from the pre-treatment was determined by the average of the leaves of the five strains. The color difference was determined by Equation 1.

[0028]

(Equation 1)

2) Evaluation method of the result The ΔE value represents the difference in the overall color tone between the one just after the harvest and the one after the harvest. The smaller the value, the closer the color tone to that immediately after harvest. 6 or less: good green retention, no significant difference between the freshly harvested one and the naked eye / fresh state 6 or more: poor green retention, yellowish to the naked eye / no freshness

(2) Results The results measured by the above method are shown in Table 5 and FIG. Good results were obtained with 10% trehalose.

[0031]

[Table 5]

[0032]

As described above in detail, the present invention relates to a method for maintaining a freshness of a plant by treating the plant with a sugar solution having a concentration of 10% or more, wherein the sugar content in the plant after the treatment is reduced. 0.4%
The present invention relates to a method for maintaining freshness of a plant, a freshness maintaining agent, and a plant provided with a high freshness maintaining effect, characterized in that the present invention provides: 1) good freshness of a plant. 2) In particular, in a green plant containing chlorophyll, an excellent holding effect of the green color tone of chlorophyll can be obtained. 3) The sugar content in the plant is adjusted to a predetermined level. Thus, an excellent freshness preserving effect not obtained by the conventional method can be obtained. 4) A high freshness preserving effect can be obtained by a simple operation of contacting a rhizome of a plant with a sugar solution. 5) Particularly effective in preserving the freshness of green vegetables. A freshness maintaining method and a freshness maintaining agent can be provided. 6)
Particularly advantageous effects are obtained such that the sugar content (absorbed sugar content) in the plant body after the treatment can be efficiently measured and managed.

[Brief description of the drawings]

FIG. 1 shows the chlorophyll content of broccoli on day 16 of refrigeration.

FIG. 2 shows a change in chlorophyll content due to a sugar immersion treatment of broccoli.

FIG. 3 shows a change in the color tone of spinach (immersion treatment for 6 hours).

Claims (9)

[Claims] The present invention is characterized in that a plant is treated with a sugar solution having a concentration of 10% by weight or more, and the sugar content in the plant after the treatment is increased by 0.4% by weight or more with respect to that before the treatment. A method for maintaining freshness of a plant. 2. The rhizome of a plant body having a concentration of 10 to 30% by weight.
Contacting the sugar solution for 10 minutes to 24 hours. 3. The method according to claim 1, wherein the sugar solution is an aqueous solution of trehalose and / or sucrose. 4. The method for maintaining the freshness of a plant according to claim 1, wherein the plant is treated with a sugar solution at 0 to 10 ° C. 5. The method for maintaining freshness of a plant according to claim 1, wherein the plant is a green plant containing chlorophyll. 6. The method according to claim 1, wherein when the plant is cultivated in hydroponics, water for cultivation is replaced with a sugar solution before harvesting, and the sugar solution is brought into contact with the root of the plant, and then harvested. Item 1 or 2
The method for maintaining freshness of a plant according to the above. 7. 10 to 30% by weight of trehalose and / or
Or a freshness preserving agent for a plant, characterized by containing sucrose. 8. A plant having a high freshness preserving effect, wherein the content of sugar in the plant is increased by 0.4% by weight or more with respect to a natural plant. 9. A method for treating a plant body with a predetermined sugar solution to maintain its freshness, wherein the volume and sugar content (Brix) of the sugar solution before and after the treatment are used as indices, and the plant body after the treatment is treated based on the indices. And measuring and managing the sugar content (absorbed sugar content) in the plant after treatment.