JP5560193B2 - Method for producing dried plant - Google Patents

Description

  The present invention relates to a method for producing a dried plant body that retains the color, fragrance and feel of the plant body and can maintain these states for a long period of time.

  Dried flowers or dried plants obtained by drying fresh flowers or plants are well known in the art. These dried flowers and the like are mainly produced by any one of a drying method by natural drying, a drying method by a desiccant, and a drying method by freeze drying (Patent Documents 1 and 2). However, neither method has preserved the color, scent, and feel of the original fresh flowers or plants.

In order to eliminate the disadvantages of dried flowers, a preserved flower that does not change its color for a long period of time is also known. Preserved flowers are close to living flowers and plants that are touched, and have been rapidly spreading in recent years. Furthermore, a preserved flower to which a scent is added is also known (Patent Documents 3 and 4).
Japanese Unexamined Patent Publication No. 3-141345 Japanese Patent Laid-Open No. 11-199401 JP 2006-52194 A JP 2007-176941

  A preserved flower is a natural flower or plant, but its color and fragrance are artificial. Preserved flowers have the advantage of imparting colors and fragrances that do not exist in nature, but on the other hand, they do not retain the colors and scents of real flowers and plants, but are merely artificial. The desire to enjoy fresh flowers and plants that are closer to nature is not satisfactory, and it is desired to provide a technology that can maintain fresh flowers and plants that are closer to nature.

  Accordingly, an object of the present invention is to provide a method for producing a dried plant body that retains the color, fragrance, and feel of plants such as fresh flowers and plants in a state close to nature and can maintain these states for a long period of time. is there.

  Based on knowledge accumulated over many years regarding plant tissue observation technology, the present inventor has found conditions under which a plant tissue can retain its color, scent and feel for a long period of time after drying. Completed.

The present invention is as follows.
[1]
A step of absorbing an aqueous solution of a saccharide and a denaturation inhibitor in a plant at a temperature of 0 to 10 ° C. (1),
A step (2) of maintaining the plant body that has absorbed the aqueous solution at a temperature in the range of −10 to −20 ° C., and a step (3) of obtaining a dried plant body by vacuum drying the obtained plant body
A method for producing a dried plant comprising:
[2]
The production method according to [1], wherein the saccharide is sucrose, fructose, or glucose.
[3]
The production method according to [1] or [2], wherein the denaturation inhibitor is a plant browning inhibitor, a chlorophyll degradation inhibitor, or a carotenoid degradation inhibitor.
[Four]
Process (1) is a manufacturing method in any one of [1]-[3] performed in the range of 6 hours-120 hours.
[Five]
Step (2) is the production method according to any one of [1] to [4], which is performed in a range of 1 hour to 24 hours.
[6]
The manufacturing method according to any one of [1] to [5], wherein the vacuum drying in the step (3) is performed at a temperature in the range of −10 to −20 ° C.
[7]
The production method according to any one of [1] to [6], further comprising a step (4) of heat-treating the dried plant obtained in the step (3).
[8]
The production method according to any one of [1] to [7], wherein the plant body is a picked flower, a cut flower, a cut foliage, or a cut branch.

  ADVANTAGE OF THE INVENTION According to this invention, the dry plant body which hold | maintained the color, fragrance, and touch which a natural fresh flower and a plant have can be provided, and this dry plant body can continue holding this color, fragrance, and touch for a long period of time. it can.

The present invention relates to a method for producing a dried plant,
A step of absorbing an aqueous solution of a saccharide and a denaturation inhibitor in a plant at a temperature of 0 to 10 ° C. (1),
A step (2) of maintaining the plant body that has absorbed the aqueous solution at a temperature in the range of −10 to −20 ° C., and a step (3) of obtaining a dried plant body by vacuum drying the obtained plant body
Is included.

Process (1)
In the step (1), an aqueous solution of saccharides and a denaturation inhibitor is absorbed in a plant at a temperature of 0 to 10 ° C. The plant used here is not particularly limited, and can be, for example, a picked flower, a cut flower, a cut foliage, or a cut branch. Moreover, there is no restriction | limiting in particular also in the kind of plant. Plants that have been regarded as dried flowers or preserved flowers so far can be used as appropriate.

  The saccharide absorbed in the plant body can be, for example, sucrose. By allowing the plant body to absorb the saccharide, the dried plant body obtained through the steps (2) and (3) can be dried while maintaining the form of the original plant tissue. Maintain ingredients and maintain feel. In general, plants transport sugar in the form of sucrose, so sucrose is the most natural sugar. However, disaccharides other than sucrose, monosaccharides, oligosaccharides, and the like can be used similarly, and examples thereof include fructose and glucose.

  Plants absorb degeneration inhibitors in addition to sugars. The denaturation inhibitor as used herein can be, for example, a cryoprotectant, a flexibility maintenance agent, a plant browning inhibitor, a chlorophyll degradation inhibitor, or a carotenoid degradation inhibitor. Examples of the cryoprotectant and the flexibility maintaining agent include glycerin. Examples of plant browning inhibitors include EDTA (ethylenediaminetetraacetic acid) used to prevent browning of plant tissue extracts. Examples of the chlorophyll degradation inhibitor include synthetic cytokinin, ascorbic acid, sodium chloride, sodium bicarbonate, and the like. Examples of carotenoid degradation inhibitors include substances that inhibit enzymes that degrade pigments such as carotenoids, and examples include sulfites. Plant browning inhibitors, chlorophyll degradation inhibitors, carotenoid degradation inhibitors, etc. can be used in combination, and a dry plant body that retains plant cell pigments and green color (chlorophyll) is obtained, and its state is long-term Kept. In the present invention, a plurality of denaturation inhibitors can be used in combination.

  The plant is partially or totally immersed in an aqueous solution containing sugar and a denaturation inhibitor to be absorbed. The concentration of the sugar and the denaturation inhibitor in the aqueous solution can be appropriately determined in consideration of the kind of the sugar and the denaturation inhibitor, the absorption conditions, and the like, both of which can be in the range of 0.1 mM to 500 mM. However, the sugar is preferably used at a relatively high concentration, and the preferred concentration is in the range of 50 mM to 300 mM. On the other hand, EDTA or the like is preferably used at a relatively low concentration, and a preferable concentration is in the range of 0.2 mM to 10 mM. In addition, for example, a cryoprotectant and a softness-maintaining agent such as glycerin can be used at a higher concentration, for example, in the range of 10 to 30%. The temperature at the time of absorption can be in the range of 0 to 0 ° C, preferably in the range of 0 to 5 ° C. The absorption time is selected in the range of, for example, 6 hours to 120 hours in consideration of the type and state of the plant body, the type of aqueous solution, and the like, and considering that the desired dry plant body is obtained. be able to. However, it is not intended to be limited to this range of time. Absorption of an aqueous solution containing a sugar and a denaturation inhibitor can be carried out either in the dark or under illumination (including sunlight), but from the viewpoint of high absorption rate, it is under illumination (including sunlight). Preferably it is done. Alternatively, it is possible to alternately repeat under darkness and under illumination (including under sunlight).

Process (2)
In the step (2), the plant body that has absorbed the aqueous solution in the step (1) is maintained at a temperature in the range of −10 to −20 ° C. In general, in winter vegetables (eg, leeks), plant cells accumulate sugar to avoid intracellular freezing when cold conditions persist. Therefore, vegetables become sweet when severe cold continues. In the present invention, paying attention to this point, in the step (2), processing in a low temperature state just before freezing is performed. The low temperature state just before freezing is in the range of -10 to -20 ° C. By performing the low temperature treatment in this range, the sugar content absorbed by the plant body is accumulated in the plant cell and forms a special intracellular structure. By performing such treatment, in the vacuum drying in the step (3), the plant being dried becomes low temperature, or even when this vacuum drying is actively carried out at a low temperature, Cells can be maintained without freezing.

  From the above viewpoint, the temperature in step (2) is preferably in the range of -12 to -18 ° C, more preferably in the range of -14 to -16 ° C. The treatment temperature in step (2) is preferably a low temperature just before freezing. The low temperature just before freezing varies depending on the plant species and pretreatment, but whether the plant has frozen can be identified by observing the cells, and after testing the presence or absence of freezing of the plant in advance, It can also be determined. In addition, the treatment time is in the range of 1 to 24 hours in consideration of the type and state of the plant, the type of the absorbed aqueous solution, etc., and considering that the desired dry plant is obtained. It can be carried out. However, it is not intended to be limited to this range. The low-temperature treatment can be performed in the dark or under illumination (including sunshine). Alternatively, it is possible to alternately repeat under darkness and under illumination (including under sunlight).

Process (3)
In step (3), the plant obtained in step (2) is vacuum-dried to obtain a dried plant. The vacuum drying in the step (3) is preferably performed at a temperature in the range of −10 to −20 ° C. from the viewpoint of obtaining a plant body having a desired color, fragrance, and feel. Due to the low temperature treatment in the step (2), the cells are in a state that is less likely to freeze than before the treatment. By drying the plant body in such a state under vacuum, it can be dried while avoiding freezing. By drying while avoiding freezing, it is possible to obtain a dried plant body that occupies most of the plant cells and avoids damage to the vacuolar membrane accumulating various degrading enzymes, thereby achieving the desired color. A dried plant body that retains fragrance and feel can be obtained. When lyophilized by a normal method, the intracellular membrane structure is destroyed, and as a result, it becomes difficult to obtain a dried plant body that retains its color, fragrance and feel.

  The vacuum drying time in step (3) takes into account the type of plant body, the state, the type of aqueous solution absorbed, the low-temperature treatment conditions, etc., and the conditions for obtaining the desired dry plant body. For example, it can be performed in the range of 1 hour to 24 hours. However, it is not intended to be limited to this range.

  The dried plant body obtained in step (3) is a dried plant body that retains the color, fragrance and feel of natural fresh flowers and plants, and for a long period (for example, 1 to 12 months), this color and fragrance. And it can continue to hold the touch.

Process (4)
Furthermore, the production method of the present invention can further include a step (4) of heat-treating the dried plant obtained in the above step (3). By heat treatment, an enzyme (for example, an enzyme that decomposes pigments or chlorophyll) contained in the dried plant can be inactivated, and the storage stability can be further improved. From the viewpoint of inactivating the enzyme, the heat treatment can be performed at a temperature of 50 to 80 ° C. for 1 minute to 60 minutes, for example.

  Hereinafter, the present invention will be described in detail with reference to examples.

Example 1
1) Rose leaf pieces were immersed in the solutions (a) to (d) and placed at 4 ° C. for 12 hours.
(a) Water
(b) Water + 1 mM EDTA
(c) Water + 0.2 M sucrose
(d) Water + 0.2 M sucrose + 1 mM EDTA

2) The leaf piece taken out from the solution was placed on a filter paper and subjected to low-temperature treatment for 3 hours with a household freezer (-15 to -20 ° C).

3) Removed from the freezer after low-temperature treatment, dried in vacuum at room temperature, and compared in shape, color and feel. The results are shown in Table 1. The criteria for evaluation are as follows.
×× Significant change × Changed ○ Close to the natural state ◎ Very close to the natural state

Example 2
Instead of vacuum drying at room temperature in Example 1, vacuum drying at −15 ° C. was performed. The shape, color, and feel were compared, and the results are shown in Table 2. Evaluation criteria are the same as in Table 2.

  In the case of Example 2, in addition to the gloss, good results were obtained for the shape and color as compared with Example 1.

Example 3
1) A cut flower of light pink rose was dipped in the solution of (a) to (c) together with the stem and leaves, and absorbed at 10 ° C. for 24 hours.
(a) Water
(b) Water + 0.2 M sucrose + 20% glycerin
(c) Water + 0.2 M sucrose + 20% glycerin + 1 mM EDTA

2) The plant body taken out of the solution was vacuum dried for 2 weeks at the sample temperature of -15 ° C together with the foliage. The shape, color, feel and fragrance of flowers, stems and leaves were compared, and the results are shown in Table 3. The evaluation criteria are the same as in Table 1.

  INDUSTRIAL APPLICABILITY The present invention is useful in the field of producing dried plants that can replace conventional dried flowers and preserved flowers.

Claims (7)

A step (1) of causing the plant body to absorb an aqueous solution of a saccharide and a denaturation inhibitor at a temperature of 0 to 10 ° C. for 6 hours to 120 hours ;
A step (2) for maintaining the plant body that has absorbed the aqueous solution at a temperature in the range of −10 to −20 ° C., and a step (3) for obtaining a dried plant body by vacuum drying the obtained plant body.
A method for producing a dried plant comprising: The production method according to claim 1, wherein the saccharide is sucrose, fructose, or glucose. The method according to claim 1 or 2, wherein the denaturation inhibitor is a cryoprotectant, a flexibility maintaining agent, a plant browning inhibitor, a chlorophyll degradation inhibitor, or a carotenoid degradation inhibitor. The process according to any one of claims 1 to 3 , wherein the step (2) is performed in a range of 1 hour to 24 hours. The manufacturing method according to any one of claims 1 to 3, wherein the vacuum drying in the step (3) is performed at a temperature in the range of -10 to -20 ° C. The manufacturing method in any one of Claims 1-3, 5, and 6 which further includes the process (4) which heat-processes the dried plant body obtained at the process (3). The production method according to any one of claims 1 to 3, 5, 6, and 7, wherein the plant body is a picked flower, a cut flower, a cut foliage, or a cut branch.