A kind of mango preservative and preparation method thereof

Abstract

The present invention proposes a mango preservative and a preparation method thereof, and belongs to the technical field of food preservation. The mango preservative raw materials of the present invention include 20-30 parts of lac, 1-6 parts of p-coumaric acid, 12-16 parts of plant essential oils, 3-6 parts of sodium polyoxyethylene fatty alcohol ether sulfate and 0.1-1 parts of α-aminoisobutyric acid by weight, and the preparation method includes the following steps: weigh each raw material by weight, and modify the lac after activating the lac and mixing it with p-coumaric acid to obtain modified lac; after mixing the modified lac with plant essential oils and α-aminoisobutyric acid, add sodium polyoxyethylene fatty alcohol ether sulfate dropwise while oscillating to obtain a mixture, and then add water to shear to obtain a mango preservative. The mango preservative of the present invention can effectively reduce the water loss of mango, while enhancing the inhibition rate of pathogens, especially the inhibition of mango anthracnose pathogens, thereby effectively reducing the incidence of mango during storage, improving the good fruit rate, and extending the shelf life of mango.

Description

Technical Field

[0001] The invention belongs to the technical field of food preservation, and in particular relates to a mango preservative and a preparation method thereof. Background Art

[0002] Mango is a tropical fruit with extremely high nutritional value. It is rich in vitamins, dietary fiber and other nutrients. It has the effects of lowering cholesterol and triglycerides, promoting intestinal motility, aiding digestion, and relieving phlegm and cough. It is deeply loved by consumers.

[0003] Mango is a fruit with respiratory climacteric. If the correct storage method is not used during storage, it will deteriorate or rot. For example, if mango is exposed to direct sunlight after harvest, the high temperature will increase the respiration rate, accelerate the ripening process, and accelerate its deterioration process. In order to delay the occurrence of mango respiration peak, low-temperature storage and controlled atmosphere storage are usually used. However, if the appropriate temperature (the most suitable temperature is 13-15°C) is not maintained during transportation and storage, it will also cause mango deterioration. For example, mango can reduce its own consumption caused by fruit respiration under low-temperature storage conditions and delay the arrival of the climacteric period. However, mango is sensitive to low temperature and is a cold-sensitive fruit. Chilling damage may occur when the storage temperature is lower than 8-10°C. Chilling damage will affect the ability of mango peel to produce ethylene, thereby affecting the normal ripening of mango. In addition, common mango diseases such as anthracnose, powdery mildew, scab, and stem rot will also affect the storage and preservation of mangoes, causing mangoes to rot and deteriorate after harvest. In order to deal with the occurrence of the above-mentioned mango diseases during the post-harvest preservation period, chemical agents are mainly used for fruit soaking. Commonly used chemical fungicides such as myclobutanil, carbendazim and pyraclostrobin, in order to unilaterally pursue preservation effects, will be used indiscriminately and abused, resulting in a high fungicide detection rate in mangoes and even excessive residues.

[0004] Therefore, the present invention provides a mango preservative and a preparation method thereof. Summary of the invention

[0005] In order to solve the above technical problems, the present invention proposes a mango preservative and a preparation method thereof. The mango preservative of the present invention can achieve green and safe preservation treatment of mangoes after picking, effectively inhibit the occurrence of diseases during the preservation process and maintain the quality of mango fruits after harvest.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] One of the technical solutions of the present invention:

[0008] A mango preservative comprises raw materials, measured by weight, including 20-30 parts of shellac, 1-6 parts of p-coumaric acid, 12-16 parts of plant essential oil, 3-6 parts of sodium fatty alcohol polyoxyethylene ether sulfate and 0.1-1 part of alpha-aminoisobutyric acid.

[0009] Preferably, the raw materials of the mango preservative include, by weight, 26 parts of shellac, 4 parts of p-coumaric acid, 13 parts of plant essential oil, 5 parts of sodium fatty alcohol polyoxyethylene ether sulfate and 0.8 parts of α-aminoisobutyric acid.

[0010] Furthermore, the plant essential oil includes one or more of clove essential oil, cinnamon essential oil, carvacrol and citronella essential oil.

[0011] The mango preservative of the present invention has green and environmentally friendly raw materials. It reduces water loss by forming a protective film, slows down nutrient loss by using antioxidant components, and inhibits microbial growth by using antibacterial components, thereby effectively extending the shelf life of mangoes, reducing decay, and maintaining the freshness and nutritional value of the fruit. Specifically:

[0012] Shellac can form a protective film on the surface of mangoes, reducing the evaporation of water on the surface of mangoes, thereby reducing the water loss rate. At the same time, as a natural substance, shellac has antibacterial properties, which can inhibit the growth of microorganisms on the surface of mangoes and reduce rot;

[0013] p-Coumaric acid has antioxidant properties, which can slow down the oxidative loss of nutrients such as vitamin C in mangoes and extend the shelf life. In addition, p-coumaric acid also has a certain antibacterial effect, which helps to inhibit the growth of bacteria and fungi on the surface of mangoes;

[0014] Plant essential oils contain a variety of active ingredients with antibacterial and antioxidant properties, which can inhibit the growth of microorganisms on the surface and inside of mangoes, reduce decay, and delay the enzymatic reaction during the ripening process of the fruit to maintain the freshness of the fruit.

[0015] As a surfactant, sodium polyoxyethylene fatty alcohol ether sulfate can enhance the dispersibility and permeability of other ingredients, help the preservative to better adhere to the surface of mangoes, and improve the preservation effect;

[0016] α-Aminoisobutyric acid can slow down the ripening and aging process of mango by regulating the metabolic pathways inside the mango, thereby extending the shelf life.

[0017] The second technical solution of the present invention:

[0018] A method for preparing the mango preservative comprises the following steps:

[0019] Weighing various raw materials according to weight, activating shellac and mixing with p-coumaric acid to modify the shellac, thereby obtaining modified shellac;

[0020] The modified shellac is mixed with plant essential oil and α-aminoisobutyric acid, and then sodium fatty alcohol polyoxyethylene ether sulfate is added dropwise while shaking to obtain a mixture, and then water is added to shear the mixture to obtain the mango preservative.

[0021] Furthermore, the step of activating the lac comprises: dissolving the lac in water to obtain a lac solution, then adding glutamine aminotransferase and heating and stirring to obtain activated lac; preferably, the concentration of the lac solution is 1-4wt.%; and / or

[0022] The mass ratio of the transglutaminase to the shellac is (0.1-0.5):100; and / or

[0023] The heating and stirring is performed at a temperature of 36-37° C. and for a time of 20-30 minutes.

[0024] p-Coumaric acid contains phenolic hydroxyl groups. Under the action of heat, shear and transglutaminase, it can react with active groups (such as hydroxyl or carboxyl) in shellac through covalent bonds to form new chemical bonds, thereby achieving the grafting modification of shellac with p-coumaric acid and generating grafted products. p-Coumaric acid itself has strong antioxidant properties, and its phenolic hydroxyl groups can provide hydrogen atoms or electrons to neutralize free radicals, thereby enhancing the antioxidant properties of shellac. In addition, p-coumaric acid itself has antibacterial activity. Through grafting modification, shellac can inherit the antibacterial properties of p-coumaric acid, thereby improving the antibacterial properties of shellac.

[0025] Furthermore, after the shellac is activated, it is mixed with p-coumaric acid at 36-37° C. for modification for 4-8 hours. After the mixing and modification, the temperature is raised to 80-90° C., kept warm for 10-20 minutes, and then cooled to room temperature to obtain the modified shellac.

[0026] Further, the dropping speed is 10-15 mL / min; and / or

[0027] The amount of water added is 50-80 times the volume of the mixture; and / or

[0028] The shearing speed is 2000-2800 rpm and the time is 30-40 minutes.

[0029] The third technical solution of the present invention:

[0030] A method for preserving mangoes comprises washing picked fresh mangoes with water and then drying them, using the mango preservative or the mango preservative prepared according to the preparation method to soak the mangoes, and then drying them naturally.

[0031] Furthermore, the fruit soaking treatment lasts for 1-2 minutes.

[0032] Compared with the prior art, the present invention has the following advantages and technical effects:

[0033] (1) The mango preservative of the present invention can form a film on the surface of mangoes, effectively reduce the water loss of mangoes by reducing the transpiration and respiration intensity of mangoes, and enhance the inhibition rate of pathogens, especially the inhibition of mango anthracnose pathogens, thereby effectively reducing the incidence of mangoes during storage, improving the rate of good fruits, and extending the shelf life of mangoes.

[0034] (2) The mango preservative of the present invention is environmentally friendly, has no chemical residue, is simple and quick to use, and has a simple process. It is an environmentally friendly mango preservative. DETAILED DESCRIPTION

[0035] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0036] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0037] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0038] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0039] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0040] In the embodiments of the present invention, "parts" means "parts by weight" unless otherwise specified.

[0041] The embodiment of the present invention provides a mango preservative. The raw materials, measured by weight, include 20-30 parts of shellac, 1-6 parts of p-coumaric acid, 12-16 parts of plant essential oil, 3-6 parts of sodium fatty alcohol polyoxyethylene ether sulfate and 0.1-1 part of alpha-aminoisobutyric acid.

[0042] Preferably, the raw materials of the mango preservative include, by weight, 26 parts of shellac, 4 parts of p-coumaric acid, 13 parts of plant essential oil, 5 parts of sodium fatty alcohol polyoxyethylene ether sulfate and 0.8 parts of α-aminoisobutyric acid.

[0043] In a preferred embodiment of the present invention, the plant essential oil includes one or more of clove essential oil, cinnamon essential oil, carvacrol and citronella essential oil; illustratively, the plant essential oils used in the embodiments of the present invention are clove essential oil, cinnamon essential oil, carvacrol and citronella essential oil, respectively, preferably clove essential oil.

[0044] The embodiment of the present invention also provides a method for preparing the mango preservative, comprising the following steps:

[0045] Weighing various raw materials according to weight, activating shellac and mixing with p-coumaric acid to modify the shellac, thereby obtaining modified shellac;

[0046] The modified shellac is mixed with plant essential oil and α-aminoisobutyric acid, and then sodium fatty alcohol polyoxyethylene ether sulfate is added dropwise while shaking to obtain a mixture, and then water is added to shear the mixture to obtain the mango preservative.

[0047] In a preferred embodiment of the present invention, the step of activating shellac comprises: dissolving shellac in water to obtain a shellac solution, then adding glutamine aminotransferase and heating and stirring to obtain activated shellac; preferably, the concentration of the shellac solution is 1-4wt.%; the mass ratio of the glutamine aminotransferase to the shellac is (0.1-0.5):100; the temperature of the heating and stirring is 36-37°C, and the time is 20-30 minutes.

[0048] In a preferred embodiment of the present invention, after activation, the shellac is mixed with p-coumaric acid at 36-37° C. for modification for 4-8 hours. After the mixing and modification, the temperature is raised to 80-90° C., kept warm for 10-20 minutes, and then cooled to room temperature (25±2° C.) to obtain the modified shellac.

[0049] In a preferred embodiment of the present invention, the dropping speed is 10-15 mL / min.

[0050] In a preferred embodiment of the present invention, the amount of water added is 50-80 times the volume of the mixture.

[0051] In a preferred embodiment of the present invention, the shearing speed is 2000-2800 rpm and the time is 30-40 minutes.

[0052] The embodiment of the present invention further provides a method for preserving mangoes, comprising washing picked fresh mangoes and then drying them, using the mango preservative or the mango preservative prepared according to the preparation method to soak the mangoes, and then drying them naturally, wherein the soaking time is 1-2 minutes.

[0053] Unless otherwise specified, the experimental methods used in the embodiments of the present invention are all conventional methods.

[0054] Unless otherwise specified, the materials, reagents, etc. used in the embodiments of the present invention can be obtained from commercial sources.

[0055] The technical solution of the present invention is further illustrated by the following embodiments.

[0056] Example 1

[0057] A method for preparing a mango preservative in this embodiment comprises the following steps:

[0058] (1) Weigh the following raw materials in parts by weight: 26 parts of shellac, 4 parts of p-coumaric acid, 13 parts of clove essential oil, 5 parts of sodium fatty alcohol polyoxyethylene ether sulfate, and 0.8 parts of α-aminoisobutyric acid;

[0059] (2) dissolving shellac in water to obtain a shellac solution with a concentration of 3 wt.%, then adding transglutaminase and heating and stirring at 36° C. for 28 minutes to obtain activated shellac, wherein the mass ratio of transglutaminase to shellac is 0.3:100, mixing and modifying the activated shellac with p-coumaric acid at 36° C. for 5 hours, heating to 86° C. after the mixing and modification, keeping the temperature for 15 minutes, and then cooling to room temperature to obtain modified shellac;

[0060] (3) The prepared modified shellac was mixed with clove essential oil and α-aminoisobutyric acid, and sodium fatty alcohol polyoxyethylene ether sulfate was added dropwise at a rate of 12 mL / min while shaking to obtain a mixture, and then 75 times the volume of water was added to the mixture, and shearing was carried out at 2500 rpm for 36 minutes to obtain a mango preservative.

[0061] Example 2

[0062] A method for preparing a mango preservative in this embodiment comprises the following steps:

[0063] (1) Weigh the following raw materials in parts by weight: 30 parts of shellac, 1 part of p-coumaric acid, 16 parts of cinnamon essential oil, 6 parts of sodium fatty alcohol polyoxyethylene ether sulfate, and 0.1 part of α-aminoisobutyric acid;

[0064] (2) dissolving shellac in water to obtain a shellac solution with a concentration of 4 wt.%, then adding transglutaminase and heating and stirring at 37° C. for 30 minutes to obtain activated shellac, wherein the mass ratio of transglutaminase to shellac is 0.5:100, and mixing and modifying the activated shellac with p-coumaric acid at 37° C. for 4 hours. After the mixing and modification is completed, the temperature is raised to 90° C., kept warm for 10 minutes, and then cooled to room temperature to obtain modified shellac;

[0065] (3) After mixing the prepared modified shellac with cinnamon essential oil and α-aminoisobutyric acid, sodium fatty alcohol polyoxyethylene ether sulfate was added dropwise at a rate of 15 mL / min while shaking to obtain a mixture, and then 80 times the volume of water was added to the mixture, and shearing was carried out at 2800 rpm for 40 minutes to obtain a mango preservative.

[0066] Example 3

[0067] A method for preparing a mango preservative in this embodiment comprises the following steps:

[0068] (1) Weigh the following raw materials in parts by weight: 20 parts of shellac, 6 parts of p-coumaric acid, 12 parts of carvacrol, 3 parts of sodium fatty alcohol polyoxyethylene ether sulfate, and 1 part of α-aminoisobutyric acid;

[0069] (2) dissolving shellac in water to obtain a shellac solution with a concentration of 1 wt.%, then adding transglutaminase and heating and stirring at 36° C. for 20 minutes to obtain activated shellac, wherein the mass ratio of transglutaminase to the shellac is 0.1:100, mixing and modifying the activated shellac with p-coumaric acid at 36° C. for 8 hours, heating to 80° C. after the mixing and modification is completed, keeping the temperature for 20 minutes, and then cooling to room temperature to obtain modified shellac;

[0070] (3) After mixing the prepared modified shellac with carvacrol and α-aminoisobutyric acid, sodium fatty alcohol polyoxyethylene ether sulfate was added dropwise at a rate of 10 mL / min while shaking to obtain a mixture, and then 50 times the volume of water was added to the mixture, and shearing was carried out at 2000 rpm for 30 minutes to obtain a mango preservative.

[0071] Example 4

[0072] A method for preparing a mango preservative in this embodiment comprises the following steps:

[0073] (1) Weigh the following raw materials in parts by weight: 26 parts of shellac, 4 parts of p-coumaric acid, 13 parts of citronella essential oil, 4 parts of sodium fatty alcohol polyoxyethylene ether sulfate, and 0.8 parts of α-aminoisobutyric acid;

[0074] (2) dissolving shellac in water to obtain a shellac solution with a concentration of 2 wt.%, adding transglutaminase, and heating and stirring at 36.5° C. for 22 minutes to obtain activated shellac, wherein the mass ratio of transglutaminase to the shellac is 0.4:100, mixing and modifying the activated shellac with p-coumaric acid at 36.5° C. for 6 hours, heating to 88° C. after the mixing and modification, keeping the temperature for 14 minutes, and then cooling to room temperature to obtain modified shellac;

[0075] (3) The prepared modified shellac was mixed with citronella essential oil and α-aminoisobutyric acid, and sodium polyoxyethylene fatty alcohol ether sulfate was added dropwise at a rate of 13 mL / min while shaking to obtain a mixture, and then 60 times the volume of water was added to the mixture, and shearing was carried out at 2200 rpm for 36 minutes to obtain a mango preservative.

[0076] Comparative Example 1

[0077] The preparation method of a mango preservative in this comparative example is the same as that in Example 1, except that p-coumaric acid is not added, and comprises the following steps:

[0078] (1) Weigh the following raw materials in parts by weight: 26 parts of shellac, 13 parts of clove essential oil, 5 parts of sodium fatty alcohol polyoxyethylene ether sulfate, and 0.8 parts of α-aminoisobutyric acid;

[0079] (2) After mixing shellac with clove essential oil and α-aminoisobutyric acid, add sodium sulfate of fatty alcohol polyoxyethylene ether dropwise at a rate of 12 mL / min while shaking to obtain a mixture, then add 75 times the volume of water of the mixture, and shear at 2500 rpm for 36 minutes to obtain a mango preservative.

[0080] Comparative Example 2

[0081] The preparation method of a mango preservative in this comparative example is the same as that in Example 1, except that clove essential oil is not added, and comprises the following steps:

[0082] (1) Weigh the following raw materials in parts by weight: 26 parts of shellac, 4 parts of p-coumaric acid, 5 parts of sodium fatty alcohol polyoxyethylene ether sulfate, and 0.8 parts of α-aminoisobutyric acid;

[0083] (2) dissolving shellac in water to obtain a shellac solution with a concentration of 3 wt.%, then adding transglutaminase and heating and stirring at 36° C. for 28 minutes to obtain activated shellac, wherein the mass ratio of transglutaminase to the shellac is 0.3:100, mixing and modifying the activated shellac with p-coumaric acid at 36° C. for 5 hours, heating to 86° C. after the mixing and modification, keeping the temperature for 15 minutes, and then cooling to room temperature to obtain modified shellac;

[0084] (3) After mixing the prepared modified shellac with α-aminoisobutyric acid, sodium fatty alcohol polyoxyethylene ether sulfate was added dropwise at a rate of 12 mL / min while shaking to obtain a mixture, and then 75 times the volume of water was added to the mixture, and shearing was carried out at 2500 rpm for 36 minutes to obtain a mango preservative.

[0085] Comparative Example 3

[0086] The preparation method of a mango preservative in this comparative example is the same as that in Example 1, except that, in step (1), the following raw materials are weighed in parts by weight: 60 parts of shellac, 4 parts of p-coumaric acid, 10 parts of clove essential oil, 2 parts of sodium fatty alcohol polyoxyethylene ether sulfate and 1.5 parts of α-aminoisobutyric acid; the remaining steps are the same.

[0087] Comparative Example 4

[0088] The preparation method of a mango preservative in this comparative example is the same as that in Example 1, except that α-aminoisobutyric acid is not added, and comprises the following steps:

[0089] (1) Weigh the following raw materials in parts by weight: 26 parts of shellac, 4 parts of p-coumaric acid, 13 parts of clove essential oil, and 5 parts of sodium fatty alcohol polyoxyethylene ether sulfate;

[0090] (2) dissolving shellac in water to obtain a shellac solution with a concentration of 3 wt.%, then adding transglutaminase and heating and stirring at 36° C. for 28 minutes to obtain activated shellac, wherein the mass ratio of transglutaminase to the shellac is 0.3:100, mixing and modifying the activated shellac with p-coumaric acid at 36° C. for 5 hours, heating to 86° C. after the mixing and modification, keeping the temperature for 15 minutes, and then cooling to room temperature to obtain modified shellac;

[0091] (3) After mixing the prepared modified shellac with clove essential oil, sodium fatty alcohol polyoxyethylene ether sulfate was added dropwise at a rate of 12 mL / min while shaking to obtain a mixture, and then 75 times the volume of water was added to the mixture, and shearing was carried out at 2500 rpm for 36 minutes to obtain a mango preservative.

[0092] Comparative Example 5

[0093] The preparation method of a mango preservative in this comparative example is the same as that in Example 1, except that sodium fatty alcohol polyoxyethylene ether sulfate is not added, and comprises the following steps:

[0094] (1) Weigh the following raw materials in parts by weight: 26 parts of shellac, 4 parts of p-coumaric acid, 13 parts of clove essential oil, and 0.8 parts of α-aminoisobutyric acid;

[0095] (2) dissolving shellac in water to obtain a shellac solution with a concentration of 3 wt.%, then adding transglutaminase and heating and stirring at 36° C. for 28 minutes to obtain activated shellac, wherein the mass ratio of transglutaminase to the shellac is 0.3:100, mixing and modifying the activated shellac with p-coumaric acid at 36° C. for 5 hours, heating to 86° C. after the mixing and modification, keeping the temperature for 15 minutes, and then cooling to room temperature to obtain modified shellac;

[0096] (3) The prepared modified shellac was mixed with clove essential oil and α-aminoisobutyric acid to obtain a mixture, and then 75 times the volume of water was added to the mixture, and sheared at 2500 rpm for 36 minutes to obtain a mango preservative.

[0097] Comparative Example 6

[0098] The preparation method of a mango preservative in this comparative example comprises the following steps:

[0099] (1) Weigh the following raw materials in parts by weight: 26 parts of shellac, 4 parts of p-coumaric acid, 13 parts of clove essential oil, 5 parts of sodium fatty alcohol polyoxyethylene ether sulfate, and 0.8 parts of α-aminoisobutyric acid;

[0100] (2) After mixing shellac, p-coumaric acid, clove essential oil, and α-aminoisobutyric acid, fatty alcohol polyoxyethylene ether sodium sulfate was added dropwise at a rate of 12 mL / min while shaking to obtain a mixture, and then 75 times the volume of water was added to the mixture, and shearing was carried out at 2500 rpm for 36 minutes to obtain a mango preservative.

[0101] Comparative Example 7

[0102] 25wt.% prochloraz aqueous solution was purchased from Hainan Zhengye Zhongnong Hi-Tech Co., Ltd.

[0103] Performance Testing

[0104] 1. Determination of the control effect on mango anthracnose

[0105] Preparation of mango anthracnose spore suspension: Take a mango anthracnose culture dish cultured at 28°C for 7 days, cut 10 bacterial cakes with a diameter of 1 cm from the outside of the colony, put them into 100 mL of PDB liquid culture medium, and culture them at 28°C and 120 rpm for 3 days. Then take 25 mL of the culture solution and filter it into a 50 mL centrifuge tube with double-layer gauze, then centrifuge it at 4000 rpm for 10 min at room temperature, carefully remove the supernatant, add 5 mL of freshly sterilized PDB culture medium, resuspend to obtain a spore suspension, count the spore concentration with a hemocytometer, and adjust the concentration of the spore suspension to 10 with PDB culture medium. 7 spores / mL.

[0106] The mangoes were washed with clean water and dried naturally. The protective and therapeutic effects of the prochloraz aqueous solution of Examples 1-4 and Comparative Example 7 were tested according to the in vitro inoculation test, and a clean water group was set as a control (CK group).

[0107] (1) Protective effect: Three circular holes with the same depth and spacing and a diameter of 3 mm were drilled on the same surface of mango fruit, and the fruit was immersed in the preservative of Examples 1-4 or clean water for 2 minutes, taken out and naturally dried. After 12 hours, 20 μL of spore suspension was dripped into each hole, and then placed in a polyethylene sealed bag and placed in a storage room without tying the bag (storage temperature is 25±2°C, relative humidity is 70%-80%). After 10 days of storage, the diameter of the lesion was measured and recorded by the cross method. Six mangoes were used for each treatment and the average value was taken.

[0108] (2) Therapeutic effect: Drill three circular holes with the same depth and spacing and a diameter of 3 mm on the same surface of the mango fruit, then drip 20 μL of spore suspension into each hole, wait for the bacterial solution to be absorbed, and soak them in the preservatives of Examples 1-4 or clean water for 2 minutes after 12 hours. Take them out and dry them naturally, then put them in a polyethylene sealed bag, and place them in a storage room without tying the mouth (storage temperature is 25±2°C, relative humidity is 70%-80%). After 10 days of storage, measure and record the diameter of the pathogen growth using the cross method. Take the average value of 6 mangoes for each treatment. And calculate the average prevention effect according to the following formula: Average prevention effect = (D ck -D t ) / D ck ×100%, where D ck is the average diameter of the lesions in the water control group (excluding the pore diameter), D t The average diameter of the lesions in the treatment group (excluding the pore diameter) is shown in Table 1.

[0109] Table 1 Determination of the control effect of each treatment group on mango anthracnose

[0110]

[0111] It can be seen from the data in Table 1 that 10 days after artificial inoculation of mango anthracnose, the clear water control treatment showed obvious symptoms of disease, and the diameter of the lesion reached 18.6-19.4 mm. After the treatment of the embodiment, whether it was a protective treatment or a therapeutic treatment, the incidence of mango anthracnose was significantly lower than that of the clear water control, and the diameter of the lesion was significantly smaller than that of the clear water control, indicating that the mango preservative prepared by the embodiment of the present invention has obvious therapeutic and protective effects on mango anthracnose.

[0112] 2. Effects of various components on the incidence, good fruit rate and weight loss rate of mango storage

[0113] 110 freshly picked "Golden Mango" mangoes were washed and dried, and the weight of each fruit was 1.2 kg. The mango preservatives of Examples 1-4 of the present invention and the mango preservatives of Comparative Examples 1-7 were used for fruit soaking treatment, respectively. There were 10 mangoes in each treatment group. The mangoes were soaked for 2 minutes and naturally dried. After storage for 30 days under the same conditions, the incidence rate, good fruit rate and weight loss rate of mangoes in each group were counted. The judging criteria for good fruit were: the area of ​​lesions accounted for less than 5% of the total area of ​​the fruit, and the weight loss rate (%) = (mass before storage - mass after storage) / mass before storage. The results are shown in Table 2.

[0114] Table 2 Effects of various components on the incidence of disease, good fruit rate and weight loss rate of mango storage

[0115]

[0116]

[0117] It can be seen from the data in Table 2 that the morbidity and weight loss rate of mango storage by the preservative prepared in the embodiment of the present invention are significantly lower than those in the comparative example, while the good fruit rate is significantly higher than that in the comparative example treatment group, indicating that the preservative prepared in the embodiment of the present invention reduces the transpiration and respiration intensity of mango, reduces the water loss of mango, and can effectively inhibit mango pathogens, and has a good preservation effect. Since p-coumaric acid itself has antibacterial activity, compared with Example 1, the addition of p-coumaric acid is omitted in Comparative Example 1, which reduces the antibacterial performance of the preservative. In addition, the lack of grafting modification of shellac with p-coumaric acid reduces the antioxidant and antibacterial performance of shellac, resulting in a large weight loss of mango during storage and a high morbidity. Comparative Examples 2, 4 and 5 omit clove essential oil, α-aminoisobutyric acid and sodium polyoxyethylene fatty alcohol ether sulfate respectively on the basis of Example 1, while Comparative Example 3 changes the dosage of each raw material on the basis of Example 1. The incidence and weight loss rate of mangoes in the above comparative examples are significantly reduced, and the good fruit rate is significantly increased, indicating that the mango preservative of the present invention maintains the quality of mango fruits after harvest under the joint action of various mechanisms of various raw materials, and none of them can be missing. In addition, compared with the prochloraz of Comparative Example 7, the raw material source of the preservative of the embodiment of the present invention is green and environmentally friendly, and effectively avoids the situation where the detection rate of fungicides is high or even the residue exceeds the standard.

[0118] The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A mango preservative, characterized in that: The raw materials include 20-30 parts of shellac, 1-6 parts of p-coumaric acid, 12-16 parts of plant essential oil, 3-6 parts of sodium fatty alcohol polyoxyethylene ether sulfate and 0.1-1 part of alpha-aminoisobutyric acid by weight.

2. The mango preservative according to claim 1, characterized in that: The raw materials include 26 parts of shellac, 4 parts of p-coumaric acid, 13 parts of plant essential oil, 5 parts of sodium fatty alcohol polyoxyethylene ether sulfate and 0.8 parts of alpha-aminoisobutyric acid by weight.

3. The mango preservative according to claim 1, characterized in that: The plant essential oil includes one or more of clove essential oil, cinnamon essential oil, carvacrol and citronella essential oil.

4. A method for preparing the mango preservative according to any one of claims 1 to 3, characterized in that: The following steps are involved: Weighing various raw materials according to weight, activating shellac and mixing with p-coumaric acid to modify the shellac, thereby obtaining modified shellac; The modified shellac is mixed with plant essential oil and α-aminoisobutyric acid, and then sodium fatty alcohol polyoxyethylene ether sulfate is added dropwise while shaking to obtain a mixture, and then water is added to shear the mixture to obtain the mango preservative.

5. The method for preparing the mango preservative according to claim 4, characterized in that: The step of activating lac comprises: dissolving lac in water to obtain lac solution, then adding glutamine aminotransferase and heating and stirring to obtain activated lac.

6. The method for preparing the mango preservative according to claim 5, characterized in that: The concentration of the shellac solution is 1-4 wt.%; and / or The mass ratio of the transglutaminase to the shellac is (0.1-0.5):100; and / or The heating and stirring is performed at a temperature of 36-37° C. and for a time of 20-30 minutes.

7. The method for preparing the mango preservative according to claim 4, characterized in that: After the shellac is activated, it is mixed with p-coumaric acid at 36-37° C. for modification for 4-8 hours. After the mixing and modification, the temperature is raised to 80-90° C., kept warm for 10-20 minutes, and then cooled to room temperature to obtain the modified shellac.

8. The method for preparing the mango preservative according to claim 4, characterized in that: The dropping speed is 10-15 mL / min; and / or The amount of water added is 50-80 times the volume of the mixture; and / or The shearing speed is 2000-2800 rpm and the time is 30-40 minutes.

9. A method for preserving mangoes, characterized in that: The picked fresh mangoes are washed and then air-dried, and the mango preservative according to any one of claims 1 to 3 or the mango preservative prepared by the preparation method according to any one of claims 4 to 8 is used to soak the mangoes, and the mangoes are naturally dried.

10. The method for preserving mangoes according to claim 9, characterized in that: The time for the fruit soaking treatment is 1-2 minutes.

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