Method for homogeneous preservation of plant material

Abstract

A method for treating a biological object, which can be a full plant or part of a plant such as foliage, ferns, or flowers, is described. The method comprises arranging the biological object in a preservative impregnation solution, wherein the entire biological object is immersed in the impregnation solution, and applying vacuum impregnation to the entire object immersed in the preservative solution, to initiate the vacuum impregnation preservation process.

Description

[0001] METHOD FOR HOMOGENEOUS PRESERVATION OF PLANT MATERIAL

[0002] FIELD OF INVENTION

[0003] The present invention pertains to a method for preserving plants or parts thereof, including flowers, through vacuum impregnation in a preservative solution.

[0004] Background of the Invention:

[0005] Preservation of plants and flowers is essential for various industries, including floral decoration, botanical research, and educational purposes. Traditional preservation methods often involve drying or chemical preservation, which can result in color loss, diminished structural integrity, or the need for lengthy processing times. Thus, there is a need for an efficient, scalable method that maintains the natural color and structure of the plant material.

[0006] SUMMARY OF INVENTION

[0007] The present invention relates to a method for preserving plants or parts thereof, including flowers, using vacuum impregnation in a preservative solution. The method comprises: arranging the biological object in a preservative impregnation solution, wherein the entire biological object is immersed in the impregnation solution, and applying vacuum impregnation to the entire object (plant or part of the plant) immersed in the preservative solution, to initiate the vacuum impregnation preservation process. The present invention provides a method that fully preserves a plant or part of a plant or flower by immersing it entirely in a preserving solution, so as to ensure homogeneous penetration of the solution into all tissues. The vacuum impregnation treatment with a preservative solution for the plant or part of the plant or flower is a robust method, resulting in complete tissue death to preserve and halt the biological living processes. Following the process, the plant or part of the plant or flower is no longer alive.In the present invention, vacuum impregnation exhibits a homogeneous pattern within the plant or part of the plant that has been treated with a preservative solution. Any differences observed stem solely from the natural variation in the plant's color prior to treatment. Description of a Specific Embodiment of the invention ;

[0008] According to one specific embodiment of the present invention, the method involves fully immersing the plant or part of the plant or flower in a preservative solution and subjecting it to vacuum impregnation to ensure thorough impregnation of the preservative solution into the tissue. The specific conditions of this method are detailed below.The preservation solution utilized during the vacuum impregnation process may comprise at least one humectant. For achieving natural coloration, food or reactive dyes are added along with antioxidants, and sometimes surfactants. The vacuum impregnation process operates within a temperature range of 25-60 degrees Celsius to minimize the viscosity of the liquid without causing damage to the plant tissue. The concentration of the humectant, which can be a polyol such as Glycerol or PEG, comprised in the preservation solution, varies depending on the specific plant or flower being preserved but typically ranges between 20% and 60% of the total solution.

[0009] The addition of food or reactive dye is essential to impart a natural color to the plant or part of the plant, as the natural color is typically lost during the preservation process. Food dye or reactive dyes that are suitable for the preservation process include tartrazine (3-100 g / L) combined with Blue patent (0.3-10 g / L), which form a good combination for imparting a green color to the plant. Antioxidants such as Ascorbic acid, Sodium Ascorbate, or Sodium metabisulfite can be utilized in concentrations range 1-5 g / L. Surfactants, like Tween 20, may or may not be included, typically in concentrations ranging from 0.1% to 1% of the preserving solution.

[0010] The operational parameters are one of the main innovations of the present invention, the method involves a Vacuum impregnation process with a minimum pressure range of 10-400 mbar. At the same time the process for fully impregnating the plant with a preserving solution needs to be at least 25 min, but depending on the volume of the preserving pot, can last 120 minutes. The process is considered finalized, when most of the air has been evacuated from the impregnation solution and small or just a minimum amount of bubbles emerge from the solution.

[0011] According to yet another embodiment, the vacuum impregnation process of preserving solution into the plant is a continuous process that can last from 25 min to 120 min in standard scenario, but will always depend on the size of the solution and plants that need to be impregnated.

[0012] Furthermore, the vacuum impregnation process for preserving a plant or part of the plant typically involves just one cycle of vacuum treatment, from atmospheric pressure to 10-400 mbar. The specific pressure range depends on the characteristics of the plant or part of the plant being treated.

[0013] According to one embodiment, the method may further involve, in some cases, a step of applying high pressure. This is a possible alternative and may be suitable for certain materials. However, it is preferrable to conduct the vacuum impregnation process without the involvement of high pressure costs to ensure commercial viability and scalability. Other additional steps may be involved according to the present invention. As a first example, according to one embodiment, the method involves a subsequent washing step comprising immersing said biological object into water tTo remove excess preservative solution from the tissue surface. This process needs to be performed swiftly to prevent the removal of the preservative from the plant or part of the plant. The procedure is conducted at room temperature. Moreover, according to yet another embodiment, the method does not include applying any special method of drying. Instead, the plants or parts of the plants or flowers are allowed to dry naturally under environmental conditions to adapt to average room conditions (40-60% relative humidity, 15-25 degrees Celsius). This is an important step, because overdrying the preserved plant will adversely affect its structure and require additional time to recover before packaging. The method involves sterilizing the water in order to decrease and / or avoid bacterial contamination. The preservant solution is normally used one time, but could be reused if the bacteria is removed with temperature treatment and the chemical will be adjusted to original concentration.

[0014] The method that has been developed focuses on a maximum impregnation possible of the tissue of a plant, or part of a plant, that can increase its weight by 20-100% depending on the nature of the plant after preservation with vacuum impregnation, but after natural drying it will be 5- 60% less that the original weight of the plant.

[0015] The protocol involves an acclimatation time, as was mentioned, after the plant or part of the plant has been vacuum impregnated with preservant solution. The plant is gently washed with water to remove the excess of solution on the tissue in a short time and let it naturally dry in room conditions (15-25 Celsius, 40-60% humidity). This will result in drying all excess solution that is on the surface of the plant. The plant or part of the plant can be allowed to dry by hanging or laying them over net surfaces, depending on the nature of the plants. The method defines a correct preservation process when the plant maintains its original weight in room conditions without drying and retains the commercial appearance of a living plant. After the drying process in room conditions, the plant or part of the plant is ready for commercialization.. The method defines proper packaging for the preserved plant or part of the plant. The plant needs to be packed to prevent moisture loss during transport, while also avoiding prolonged compression, as this can affect its natural shape. According to a second aspect of the present invention, a method for preserving a plant or part of a plant or flower is provided. This method involves subjecting the plant to vacuum impregnation, and in some instances, preferrably employing vacuum impregnation, in a preservative impregnation solution.

[0016] Embodiments relating to this aspect are provided below in the section “Embodiments - a second aspect of the present invention”.

[0017] TESTS

[0018] A Comparative test was done using different plant species in order to understand the effect of the vacuum preservation process. This method involves vacuum impregnation with preservant solution, with standard preserving formula and comparing treated and untreated (control) species.

[0019] Chamaecyparis lawsoniana

[0020] Entire plants of Chamaecyparis lawsoniana ellwoodii local nursery in Tbilisi, Georgia, were used as a plant to be tested.

[0021] Testings of entire Chamaecyparis plant.

[0022] The new method involved a full plant preservation with vacuum impregnation. The protocol used was as follows: a pressure falling time of 25 minutes, followed by a holding time of 15 minutes (until most of the bubbling stopped), and then a 5 -minute rising time to atmospheric pressure. The minimum vacuum holding was at 10 mbar 40% glycerol solution was used as a preservative solution.

[0023] The preservative solution comprises 40% food-grade glycerine, 3.5 g / L tartrazine, 0.55 g / L Blue patent, 1 mL / L Tween 20, and 3 g / L of antioxidant Ascorbic acid. The solution was maintained at 50 degrees Celsius.To run the test, 9 full plants were preserved with vacuum impregnation and a control group with the same number of plants was left untreated.

[0024] All plants were alive and all solid or substrate was removed, roots cleaned in order to prepare the plant for the Vacuum preservation process, the weight of each fresh plant was recorded before treatment. The results of the testings are provided in table 1 below. There are 2 groups, treated and utreated plants. Weights were recorded on a daily basis, and the condition was a room temperature and

[0025] 30-50% HR.

[0026] Plants were received fresh, and all of them were processed at the same time in the same room conditions.

[0027] After the test, plants were suspended on a rack, and their weights were recorded daily. For the control plants, the same process of soil removal and root cleaning was done, plants were suspended for a similar time as the treated ones.

[0028] Control and treated plants were weighed everyday in order to evaluate the weight lost due dehydration in room conditions (40-60% HR), 20-30 degrees of Celsius.

[0029] The test finalizes when there is no weight lost from the plants treated, normally 7-12 days after the test.

[0030] As a result, the following should be stated.

[0031] A preserved plant must keep a natural looking color and homogenic structure after

[0032] Vacuum preservation.

[0033] The control plants will lose their weight faster than treated plants, as with the color.

[0034] Preserved plants will lose their weight even below original weight, and must maintain a shape of a natural looking plant.

[0035] Table 1. Chamaecyparis lawsoniana test (Vacuum Impregnation test)

[0036] Data were collected on a daily basis.

[0037] The results of this new method, involving vacuum impregnation with a preservative solution of a full plant, demonstrate the noticeable effects of the preservative solution on the plants. It maintains them with a similar shape and color to that of a real plant for an extended period, compared to a control group. This is a big advantage as compared to conventional methods that involve deeping by normal diffusion and take 1-25 days to be preserved, with all disadvantages of diffusion vs Vacuum impregnation.

[0038] This is the first protocol that involves full plants, including roots, that avoid many limitations of the conventional preservation methods. Table 2 shows Comparison of plant preserving methods.

[0039] Test 2

[0040] Stems of Asparagus virgatum

[0041] In the new method that involves a part of the plant preservation with vacuum impregnation, the protocol used was as follows: a pressure falling time of 25 min; holding time of 15min; (most of the bubbling stops); and then 5 min of rising time to atmospheric pressure. The minimum vacuum holding was at 10 mbar. 40% solution of glycerol was used as a preservative solution. The preservative solution contains 40% food-grade glycerine, 3.5 g / L tartrazine, 0.55 g / L Blue patent, 1 mL / L Tween 20, and 3 g / L of antioxidant Ascorbic acid. The solution was maintained at 50 degrees Celsius.To run the test, 9 repetitions were used with a weight range of 40-70g Each was preserved with vacuum impregnation and control group with the same number of bunches was left untreated All plants were alive and stems were cutted from fresh plants at the same time, to prepare the plant for the Vacuum preservation process. The weight of each fresh bunch was recorded before treatment.

[0042] '[he results of the tests are presented in the table 2 below.

[0043] Table 2. Asparagus virgatum test (Vacuum Impregnation test) There are 2 groups, treated and non-treated bunches, weights were recorded on a daily basis, and the condition was a room temperature and 30-50% HR.

[0044] Bunches of asparagus stems were received fresh, and all of them were processed at the same time in the same room conditions. the stems were suspended on a rack, and their weights were recorded daily. For the control stems, the same process was applied, plants were suspended for the same time as the treated ones.

[0045] Control and treated plants were weighed daily in order to evaluate the weight lost due to dehydration in room conditions (40-60% HR), 20-30 degrees Celsius.

[0046] The test finalizes when there is no weight lost from the plants treated, normally 7-12 days after the test.

[0047] In result, the following should be stated.

[0048] A preserved stem must keep a natural looking color and homogenic after Vacuum preservation.

[0049] The control stems will lose their weight faster than treated plants, as with color.

[0050] Preserved stems will lose their weight even below to the original weight, and must maintain a shape as a natural looking plant.

[0051] Embodiments - a Second Aspect of the Present Invention

[0052] The method for preserving biological material involves immersing all the plant in a preservant solution. After the plant, foliage or flower is subjectrd to a Vacuum impregnation process as main treatment.

[0053] The method is suitable to treat a full plant including roots, part of the plant such as foliage and flowers.

[0054] The method used either for a full plant with roots a part of the plant like foliage or a flower, is arranging the material in a preservant solution, this involve always a fully immerse the plant, part of the plant or flower into the preservant solution and applying vacuum impregnation to the preservant solution, when the fully plant, part of plant or foliage is immerse in the preservant solution.

[0055] The method according to embodiments 1-3 involves vacuum impregnation and the impregnation solution comprises at least one Glycol, this can be PEG or Glycerine or combination of them. The method according to any of embodiments 1-4, wherein the preservant impregnation solution comprises at least one additive being an antioxidant and surfactant.

[0056] The method according to any of embodiments 1-4, wherein the preservant impregnation solution comprises at least one antioxidant e.g. Ascorbic acid, Sodium ascorbate, Sodium metabisulfite a surfactant e.g. tween 20 or combination of them.

[0057] 7. The method according to any of the preceding embodiments, wherein the method involves vacuum impregnation in a minimum pressure range of 10-400 mbar.

[0058] 8. The method according to any of the preceding embodiments, wherein the method is performed during a total treatment time for applying vacuum impregnation of more than 25 minutes, process will finish when impregnation solution will mostly stops bubbling, and will be hold for 15 min, before stop vacuum and release the pressure.

[0059] 9. The method according to embodiment 8, wherein the method involves applying vacuum impregnation and wherein the total treatment time for applying vacuum impregnation is maximum 60 minutes, preferably maximum 25 minutes plus 15 min holding pressure (based on a 51t impregnation liquid).

[0060] 10. The method according to embodiment 8 or 9, wherein the method involves vacuum impregnation in at least twx> phases, said two phases being a falling step when the pressure is decreased to a certain low pressure (10-400 mbar) and then a pressure rising step where the pressure is increased to atmospheric level and wherein the total treatment time for applying vacuum impregnation for said at least two phases will depend on the size of the solution and plants treated.

[0061] 1 1 . The method according to embodiment 10, wherein the method also includes a minimum pressure holding step in which the low pressure is kept or substantially kept at the low' pressure before the pressure rising step, and wherein the holding step preferably is performed during maximum 15 min, more preferably maximum 10 min.

[0062] 12. The method according to any of the preceding embodiments, wherein the method involves just one vacuum impregnation cycle, preferably from atmospheric pressure to the minimum pressure and back to atmospheric pressure again in one vacuum impregnation cycle.

[0063] 13. The method according to any of the preceding embodiments, wherein the method involves a subsequent washing step comprising immersing said biological object into w'ater to wash sugars and / or other substances from the surface of the biological object. 14. The method according to any of the preceding embodiments, wherein the biological object is subjected to a drying step after vacuum impregnation, preferably subsequent to a washing step, said drying step being an acclirnatation step.

[0064] 15. The method according to embodiments 14, wherein the drying step is performed at a temperature of 20-30° C. with HR 30-50%

[0065] 16. The method according to embodiments 14 or 15, wherein the drying step is performed during at least 5-6 days, preferably at least 10 days.

[0066] 17. lire method according to any of embodiments 15-16, wherein the drying period involves putting the biological object on a net material or hanging to remove water from surfaces of the biological object.

Claims

CLAIMS1. A method for treating a biological object such as an entire plant, part of the plant or flower, the method comprising: arranging the biological object in an preserving impregnation solution so that the entire biological object is immersed in the preserving impregnation solution, and applying vacuum impregnation, to all parts of the biological object immersed into the preserving mpregnation solution.

2. 'The method according to claim 1, wherein the preserving impregnation solution comprises at least one additive being an antioxidant or surfactant.

3. The method according to claim 1, wherein the preserving impregnation solution comprises at least one of Glycol such as Glycerine or PEG and additive of antioxidant such as Ascorbic acid, Sodium ascorbate or Sodium metabisulfite or combination thereof, an surfactant agent such as tween 20.

4. The method according to claim 1, wherein the method involves vacuum impregnation in a minimum pressure range of 10-400 mbar.

5. 'The method according to claim 1, wherein the method is performed during a total treatment time for applying vacuum impregnation until most of the preserving vacuum impregnation solution is degassed.

6. The method according to claim 5, wherein the total treatment time for applying vacuum impregnation is at least 40 min.

7. The method according to claim 5, wherein the method involves vacuum impregnation in at least two phases, said two phases being a falling step when the pressure is decreased and then a pressure rising step where the pressure is increased to atmospheric level, and wherein the total treatment time for applying vacuum impregnation for said at least two phases proceeds until most of the preserving vacuum impregnation solution is degassed.

8. The method according to claim 7, wherein the method further comprises a minimum pressure holding step in which the low' pressure is maintained or substantially maintained before the pressure rising step, and wherein the holding step preferably is performed for a maximum of 15 minutes, preferably a maximum of 10 minutes.

9. The method according to claim 1 , wherein the method involves one vacuum impregnation cycle, preferably from atmospheric pressure to the miniminn pressure and back to atmospheric pressure again in the vacuum impregnation cycle.

10. The method according to claim 1 , wherein the method involves a subsequent washing step comprising immersing said biological object into water to wash away any excess preservative solution from the plant tissue.

11. The method according to claim 1 , wherein the biological object is subjected to a drying step after vacuum impregnation, preferably subsequent to the washing step, said drying step being an acclimatation step.

12. The method according to claim 12, wherein the drying step is performed at a temperature of 20-30° C; and HR of 30-50%.

13. The method according to claim 11, wherein the method further comprises a drying step performed for at least 6 days, preferably at least 12 days or until the biological object reaches a Humidity equilibrium with the environment.

14. The method according to claim 12, wherein the drying step involves removing water from surfaces of the biological object and reaching an equilibrium with environmental conditions.

15. The method according to claim 12, wherein the method further comprises a resting step that involves placing the biological object on a net or hanging material to reme water from the surfaces and to allow it to reach equilibrium with its surrounding environment.

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