Adsorption type fruit preservative and preparation method thereof
By preparing an adsorbent fruit preservative containing fresh acacia tree leaves, organic acids, organic bases, and inorganic bases, the problems of harmful chemical preservatives and complex physical preservation equipment have been solved, achieving extended fruit preservation time and improved adsorption, making it suitable for industrial production.
Patent Information
- Application Number
- CN202511139740.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-14
- Publication Date
- 2026-03-03
AI Technical Summary
Among existing fruit preservation methods, chemical preservatives are harmful to human health, while physical preservation methods are costly and require complex equipment, making them difficult to widely apply in industrial production. This leads to difficulties in fruit storage and long-distance transportation, as well as high post-harvest loss rates.
An adsorbent fruit preservative is prepared by using fresh acacia tree leaves, organic acids, organic bases, ethanol and inorganic bases. The preservative is made into a viscous or moist granular form by soaking, concentrating and neutralizing to form a buffer system, and is used for fruit preservation under normal temperature or refrigeration conditions.
It significantly extends the shelf life of fruits, improves adsorption, simplifies the preparation process, reduces equipment requirements, is easy to industrialize, is environmentally friendly, and has a remarkable preservation effect.
Smart Images
Figure CN121587316A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to preservatives, specifically to an adsorbent fruit preservative and its preparation method. Background Technology
[0002] Fresh fruit is a typical perishable agricultural product. Due to its vigorous physiological activity after harvest, fruit produces carbon dioxide through respiration and releases ethylene, a ripening agent, during ripening and senescence, which is detrimental to storage and preservation. Furthermore, fresh fruit has a high water content and is rich in nutrients needed by various microorganisms, making it extremely prone to spoilage. Therefore, it is generally difficult to store and transport over long distances, resulting in high post-harvest losses and often leading to bumper harvests but low profits. With the continuous improvement of people's living standards, higher demands are being placed on fruit preservation. Meanwhile, with the development of agricultural production, fruit yields are constantly increasing. Due to its characteristics, the harvest period is often concentrated, making the issues of preservation, storage, and transportation even more prominent.
[0003] Currently, fruit preservation methods are mainly divided into physical and chemical methods. Physical methods include low-temperature storage, controlled atmosphere storage, depressurization storage, and electromagnetic radiation storage. Among these, more advanced preservation technologies include critical low-temperature high-humidity preservation, intercellular water-structured controlled atmosphere storage, and ozone controlled atmosphere storage. While these methods are widely used, they require specialized equipment, are complex to operate, are costly, and face challenges in large-scale application. Chemical methods primarily use preservatives. Common chemical preservatives include coatings, ethylene treatment agents (absorbents), and bactericides and preservatives. However, these preservatives contain many chemical components, which are detrimental to human health. In industrial production, fruit preservation methods are limited by large production volumes, making it difficult to achieve satisfactory results using only physical preservation methods. There is an urgent need for a harmless, highly efficient fruit preservative that can be applied to industrial production. Summary of the Invention
[0004] To address the health risks associated with chemical preservation methods and the limited product yield of purely physical preservation methods, this invention provides an adsorbent fruit preservative and its preparation method. After using this preservative, the preservation time of fruits under normal temperature or refrigeration conditions is significantly increased compared to those under normal temperature or refrigeration conditions without this preservative, and the permeability and adsorption properties are also greatly improved.
[0005] To achieve the above objectives, the present invention provides an adsorbent fruit preservative, which, by weight, comprises the following components: 10-15 parts of fresh acacia tree leaves, 15-30 parts of organic acid, 5-15 parts of organic alkali, 10-20 parts of ethanol, and 10-30 parts of inorganic alkali.
[0006] The functions of each component in this invention are as follows: Acacia tree leaves are rich in natural plant compounds such as polyphenols, flavonoids, and tannins. These components partially dissolve during ethanol extraction, which is the source of the preservative's antioxidant and antibacterial properties. On the other hand, after crushing and concentration, the incompletely dissolved plant residue retains its plant fiber structure and microporous morphology, forming a natural adsorption network. This network has a large specific surface area and abundant functional groups, enabling it to adsorb volatile organic compounds such as ethylene gas released by the fruit during ripening and respiration.
[0007] Organic acids: can chelate metal ions and inhibit enzymatic browning. They form buffer systems with basic compounds, regulating the acidity of the system, inhibiting microbial growth, reducing the biological activity of ethylene, and delaying ripening.
[0008] Organic bases: They are weakly basic and can form a buffer system with citric acid. The amino, guanidinium, and quaternary ammonium groups in their structure can participate in the chemisorption or electrostatic adsorption of ethylene, etc.
[0009] Ethanol: It is used as an extraction solvent to dissolve the active ingredients in acacia leaves and also has antibacterial properties.
[0010] Inorganic bases: They are alkaline and can form a buffer system with citric acid, thus enhancing pH stability.
[0011] Acacia tree leaves provide antioxidant active substances (polyphenols, flavonoids) and a plant fiber adsorption framework, possessing both slow-release and adsorption functions. They slowly release antioxidant active ingredients and adsorb gases such as ethylene released from fruits. Furthermore, the pH of the system is stably regulated through the neutralization of organic bases, inorganic bases, and organic acids. Inorganic bases can rapidly neutralize organic acids, forming a buffer structure, while organic base components, while maintaining buffering capacity, provide ethylene adsorption sites and synergistically enhance the fruit preservation effect. The buffer system serves two purposes: firstly, it stabilizes the entire microenvironment; without a buffer system, the adsorbent material of the preservative would experience decreased activity or structural changes due to drastic pH changes; secondly, the weakly acidic buffer system also inhibits oxidation, inhibits enzymatic browning, and maintains the color of the fruit peel, thereby extending the storage period.
[0012] Preferably, the adsorbent fruit preservative comprises the following components by weight: 12-15 parts of fresh acacia leaves, 20-25 parts of organic acid, 8-10 parts of organic alkali, 15-20 parts of ethanol and 15-20 parts of inorganic alkali.
[0013] Preferably, the organic acid is one or more of citric acid, tartaric acid, and malic acid.
[0014] Preferably, the organic base is one or more of chitosan, betaine, L-arginine, and L-lysine.
[0015] Preferably, the inorganic base is one or more of sodium hydroxide, potassium hydroxide, sodium bicarbonate, disodium hydrogen phosphate, and aluminum hydroxide.
[0016] A second aspect of the present invention provides a method for preparing the above-mentioned adsorbent fruit preservative, which includes the following steps: S1. After crushing fresh acacia leaves, soak them in a mixed solution of citric acid and ethanol, then filter out the residue to obtain slurry. S2. Remove 60%-80% of the ethanol from the slurry prepared in S1 to obtain a concentrated slurry; S3. Add organic and inorganic bases to the concentrated slurry prepared in S2 to obtain an adsorbent fruit preservative.
[0017] Specifically, in step S1, the pH value of the mixed solution is 3.5-6.5, and the ethanol concentration is 50-80 wt%.
[0018] A pH of 3.5-6.5 is beneficial for the extraction of active ingredients and the creation of an antibacterial environment.
[0019] Specifically, in step S1, the crushed acacia leaves are less than or equal to 100 mesh.
[0020] Specifically, in step S1, the soaking time is 30-60 minutes.
[0021] Specifically, the adsorbent fruit preservative is refrigerated at 2-5℃.
[0022] First, extract the active ingredients from fresh acacia leaves. After extraction, the slurry is coarsely filtered to remove large plant debris, retaining a suspension containing active ingredients and microparticles. Concentrating the system enriches the active ingredients and plant particles, providing a more stable foundation for subsequent adsorption enhancement and pH adjustment. Adding organic and inorganic alkalis to the concentrated slurry forms a weakly acidic buffer system with citric acid. This maintains the acid-base stability of the preservative system, preventing pH fluctuations from affecting the stability of polyphenolic components and ethylene adsorption capacity. After adjustment, the preservative is sealed and packaged, then refrigerated at 2–5°C to prevent microbial growth, oxidation of active ingredients, and component volatilization or stratification. The final adsorbent fruit preservative is a viscous slurry or moist granules, packaged in breathable filter bags, and placed inside fruit packaging containers to achieve a non-contact preservation effect.
[0023] Through the above technical solution, the present invention achieves the following beneficial effects: This invention discloses a novel adsorbent fruit preservative prepared from fresh acacia tree leaves, organic acids, organic bases, ethanol, and inorganic bases. Compared with traditional fruit preservatives, this novel adsorbent fruit preservative exhibits a significantly more pronounced preservation effect. After using this preservative, the preservation time of fruit under normal temperature or refrigeration conditions is significantly increased compared to the same conditions without this preservative, and the adsorption capacity is also greatly improved. Furthermore, the preparation method is simple, easy to control, and requires minimal equipment, making it suitable for industrial production. The preparation process also produces no volatile harmful substances, which is beneficial to environmental protection and the health of production personnel. Attached Figure Description
[0024] Figure 1 This is a schematic diagram illustrating the preparation of the adsorbent fruit preservative of the present invention; Figure 2 The image shows a comparison of cherries treated with the adsorption fruit preservative of Example 1 (bottom) for 15 days, including a blank control group (top), other similar products on the market (middle), and cherries (bottom). Detailed Implementation
[0025] The specific embodiments of the present invention will be described in detail below with reference to examples. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.
[0026] Example 1 The raw material formula of the adsorbent fruit preservative consists of the following components in parts by weight: 15 parts fresh acacia leaves, 25 parts citric acid, 10 parts chitosan, 5 parts L-arginine, 20 parts ethanol, and 15 parts sodium bicarbonate.
[0027] Reference Figure 1 As shown, its preparation method is as follows: S1. Prepare an ethanol solution with citric acid aqueous solution at room temperature and pressure, with an ethanol concentration of 50 wt%. S2. Crush fresh acacia leaves to below 100 mesh, add the prepared ethanol solution, soak for 30 minutes, and then filter to remove residue. S3. Remove 50% of the ethanol from the slurry prepared in S2 under vacuum at near room temperature. S4. The concentrated slurry prepared in S3 is neutralized to a slightly acidic state with chitosan, L-arginine and sodium bicarbonate and then placed in a refrigerated environment for later use. The refrigeration temperature is 2℃-5℃, and an adsorbent fruit preservative can be obtained.
[0028] Example 2 The raw material formula of the adsorbent fruit preservative consists of the following components in parts by weight: 12 parts fresh acacia leaves, 10 parts malic acid, 10 parts citric acid, 10 parts betaine, 18 parts ethanol and 10 parts potassium hydroxide.
[0029] Its preparation method is as follows: S1. Prepare an ethanol solution with citric acid aqueous solution at room temperature and pressure, with an ethanol concentration of 80 wt%. S2. Crush fresh acacia leaves to below 100 mesh, add the prepared ethanol solution, soak for 60 minutes, and then filter to remove residue. S3. Remove 50% of the ethanol from the slurry prepared in S2 under vacuum at near room temperature. S4. After neutralizing the concentrated slurry prepared in S3 to a slightly acidic state with betaine and potassium hydroxide, place it in a refrigerated environment for later use. The refrigeration temperature is 2℃-5℃, and an adsorbent fruit preservative can be obtained.
[0030] Example 3 The raw material formula of the adsorbent fruit preservative consists of the following components in parts by weight: 13 parts fresh acacia leaves, 30 parts tartaric acid, 4 parts chitosan, 4 parts L-lysine, 15 parts ethanol, 10 parts potassium hydroxide, and 10 parts disodium hydrogen phosphate.
[0031] Its preparation method is as follows: S1. Prepare an ethanol solution with citric acid aqueous solution at room temperature and pressure, with an ethanol concentration of 60 wt%. S2. Crush fresh acacia leaves to below 100 mesh, add the prepared ethanol solution, soak for 40 minutes, and then filter to remove residue. S3. Remove 50% of the ethanol from the slurry prepared in S2 under vacuum at near room temperature. S4. The concentrated slurry prepared in S3 is neutralized to a slightly acidic state with chitosan, L-lysine, potassium hydroxide and disodium hydrogen phosphate and then placed in a refrigerated environment for later use. The refrigeration temperature is 2℃-5℃, and an adsorbent fruit preservative can be obtained.
[0032] Example 4 The raw material formula of the adsorbent fruit preservative consists of the following components in parts by weight: 10 parts fresh acacia leaves, 15 parts citric acid, 5 parts chitosan, 25 parts ethanol, 15 parts sodium hydroxide, and 15 parts aluminum hydroxide.
[0033] Its preparation method is as follows: S1. Prepare an ethanol solution with citric acid aqueous solution at room temperature and pressure, with an ethanol concentration of 70 wt%. S2. Crush fresh acacia leaves to below 100 mesh, add the prepared ethanol solution, soak for 50 minutes, and then filter to remove residue. S3. Remove 50% of the ethanol from the slurry prepared in S2 under vacuum at near room temperature. S4. Neutralize the concentrated slurry prepared in S3 with chitosan, sodium hydroxide, and aluminum hydroxide to a slightly acidic state, and then place it in a refrigerated environment for later use. The refrigeration temperature is 2℃-5℃, and an adsorbent fruit preservative can be obtained.
[0034] Comparative Example 1 Other conditions are the same as in Example 1, except that the acacia tree leaves and ethanol are omitted.
[0035] Comparative Example 2 Other conditions are the same as in Example 1, except that only acacia tree leaves and ethanol are retained.
[0036] Test case Select cherries of the same variety, free from mechanical damage, mold, and rot, and divide them into several groups, each group containing 250 g: Group 1: After rinsing with clean water, place in a 5L sealed food storage container and let it drain in a ventilated place.
[0037] Group 2: After rinsing with clean water, place in a 5L sealed food storage container, drain in a ventilated place, and treat with 1-MCP (manufacturer: Xi'an Beinonghua Crop Protection Co., Ltd.), a commonly used preservative.
[0038] Group 3: After rinsing with clean water, place in a 5L sealed food storage container, drain the water in a ventilated place, and treat with the adsorbent fruit preservative prepared in Example 1 (5g, placed in a breathable filter bag, the same below).
[0039] Group 4: After rinsing with clean water, place in a 5L sealed food storage container, drain in a ventilated place, and treat with the adsorbent fruit preservative (5g) prepared in Example 2.
[0040] Group 5: After rinsing with clean water, place in a 5L sealed food storage container, drain in a ventilated place, and treat with the adsorbent fruit preservative (5g) prepared in Example 3.
[0041] Group 6: After rinsing with clean water, place in a 5L sealed food storage container, drain in a ventilated place, and treat with the adsorbent fruit preservative (5g) prepared in Example 4.
[0042] Group 7: After rinsing with clean water, place in a 5L sealed food storage container, drain in a ventilated place, and treat with the adsorbent fruit preservative (5g) prepared in Comparative Example 1.
[0043] Group 8: After rinsing with clean water, place in a 5L sealed food storage container, drain in a ventilated place, and treat with the adsorbent fruit preservative (5g) prepared in Comparative Example 2.
[0044] Each group of cherries was stored at 4℃. The mold rate, weight loss rate, firmness, and vitamin C content of the cherries were monitored regularly, and the results are shown in Tables 1-4.
[0045] Table 1. Mold Rate Results (%)
[0046] Table 2 Weight loss rate results (%)
[0047] Table 3 Hardness results (kg / cm) 2 )
[0048] Table 4. Vitamin C content results (mg / 100g)
[0049] like Figure 2 As shown in Tables 1-4, compared with the control group, cherries treated with the adsorbent fruit preservative prepared in the example for 15 days had fuller fruit shape, glossy skin, no mold or wrinkling, and still maintained good edibility; cherries treated with other preservatives showed dents, mold, wrinkling, and stem loss; cherries in the control group showed obvious dents, dull skin, mold, wrinkling, and stem loss.
[0050] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.
[0051] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.
[0052] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.
Claims
1. An adsorbent fruit preservative, characterized in that, By weight, it includes the following components: 10-15 parts fresh acacia tree leaves, 15-30 parts organic acid, 5-15 parts organic base, 10-20 parts ethanol and 10-30 parts inorganic base.
2. The adsorbent fruit preservative according to claim 1, characterized in that, By weight, it includes the following components: 12-15 parts fresh acacia tree leaves, 20-25 parts organic acid, 8-10 parts organic base, 15-20 parts ethanol and 15-20 parts inorganic base.
3. The adsorbent fruit preservative according to claim 1 or 2, characterized in that, The organic acid is one or more of citric acid, tartaric acid, and malic acid.
4. The adsorbent fruit preservative according to claim 1 or 2, characterized in that, The organic base is one or more of chitosan, betaine, L-arginine, and L-lysine.
5. The adsorbent fruit preservative according to claim 1 or 2, characterized in that, The inorganic base is one or more of sodium hydroxide, potassium hydroxide, sodium bicarbonate, disodium hydrogen phosphate, and aluminum hydroxide.
6. The method for preparing the adsorbent fruit preservative according to any one of claims 1 to 5, characterized in that, Includes the following steps: S1. After crushing fresh acacia leaves, soak them in a mixed solution of citric acid and ethanol, then filter out the residue to obtain slurry. S2. Remove 60%-80% of the ethanol from the slurry prepared in S1 to obtain a concentrated slurry; S3. Add organic and inorganic bases to the concentrated slurry prepared in S2 to obtain an adsorbent fruit preservative.
7. The preparation method according to claim 6, characterized in that, In step S1, the pH value of the mixed solution is 3.5-6.5, and the ethanol concentration is 50-80 wt%.
8. The preparation method according to claim 6, characterized in that, In step S1, the crushed acacia leaves are less than or equal to 100 mesh.
9. The preparation method according to claim 6, characterized in that, In step S1, the soaking time is 30-60 minutes.
10. The preparation method according to claim 6, characterized in that, The adsorbent fruit preservative is refrigerated at 2-5℃.