阅读说明：本技术 一种具有保鲜作用的姜黄素纳米乳液及制备方法 (Curcumin nano-emulsion with fresh-keeping effect and preparation method thereof ) 是由 张铁华 张叶 王恩发 林万君 于 2021-03-15 设计创作，主要内容包括：本发明提供的提供一种具有保鲜作用的姜黄素纳米乳液及制备方法,采用碱溶酸沉法提取林蛙卵蛋白,在溶解过程中加入活性炭吸附的步骤,使溶解液上清的颜色得到改善,在酸沉后用乙醇洗涤所得沉淀,有效去除了原料的腥味,并提高了蛋白提取率。然后将林蛙卵蛋白通过糖基化改性,大大提高了溶解性和乳化性,然后作为乳化剂制备均匀稳定具有抑菌保鲜作用的姜黄素纳米乳液。制备得到的产品呈均匀乳白色,包埋率在90%以上,气味良好无腥味,液滴粒径在300nm-400nm之间,常温环境下储藏稳定性良好,本发明产品无污染可降解,成本低廉,有良好的市场前景。(The invention provides a curcumin nano-emulsion with fresh-keeping function and a preparation method thereof, which adopts an alkali-dissolving acid-precipitation method to extract woodfrog egg protein, adds a step of activated carbon adsorption in the dissolving process to improve the color of the supernatant of the dissolving solution, washes the obtained precipitate with ethanol after acid precipitation, effectively removes the fishy smell of the raw materials and improves the protein extraction rate. Then the woodfrog egg protein is modified by glycosylation, so that the solubility and the emulsibility are greatly improved, and then the modified woodfrog egg protein is used as an emulsifier to prepare the uniform and stable curcumin nano emulsion with the antibacterial and fresh-keeping effects. The prepared product is uniform and milky white, the embedding rate is more than 90%, the smell is good, no fishy smell exists, the particle size of liquid drops is between 300nm and 400nm, the storage stability is good under the normal temperature environment, the product is pollution-free and degradable, the cost is low, and the market prospect is good.)

1. A preparation method of curcumin nanoemulsion with a fresh-keeping effect is characterized by comprising the following steps:

(1) taking a proper amount of rana chensinensis eggs, drying for 2-4 h at 40-50 ℃, crushing and sieving with a 60-mesh sieve;

(2) taking egg powder, using n-hexane to shake at constant temperature for 4 h for degreasing at the temperature of 40 ℃ according to the liquid-material ratio of 1:8 (g/mL), centrifuging, repeatedly leaching for three times, and removing the leaching liquor;

(3) mixing the defatted rana japonica egg powder prepared in the step (2) with water according to a ratio of 1: 8-20 (g/mL), adjusting the pH value to 11.0, adding activated carbon powder, stirring in a constant-temperature water bath at 50 ℃ for 60-120 min, and centrifuging to collect supernatant; extracting twice repeatedly, and mixing the supernatants;

(4) adjusting the pH value of the supernatant obtained in the step (3) to 4.5, standing at 4 ℃ for 6-12 h, and centrifuging;

(5) collecting the precipitate; washing with 70% ethanol for 3 times, washing the precipitate with distilled water for 3 times, adjusting pH to 7.0 each time, and stirring to redissolve the precipitate; freeze-drying for 24-72 h to obtain deodorized rana chensinensis egg protein powder;

(6) preparing the rana chensinensis egg protein solution and the xylose solution with the same mass concentration, which are prepared in the step (6), and stirring for dissolving to fully hydrate the sample; mixing a protein solution and a sugar solution according to a volume ratio of 1: 0.5-2;

(7) adjusting the pH value of the solution prepared in the step (6) to 7, pouring the solution into a closed container, placing the container in a constant-temperature heating magnetic stirrer to react for 1-6 h at the temperature of 60-80 ℃, cooling to room temperature after the reaction is finished, centrifuging for 15min at 4000 g, and freeze-drying the supernatant to obtain glycosylated rana chensinensis egg protein powder;

(8) dissolving glycosylated rana chensinensis egg protein powder in distilled water to obtain a protein solution with the concentration of 1-5% (w/v); stirring the protein solution at room temperature for 2-6 h, and adjusting the pH of the fully hydrated protein solution to be =7 for later use;

(9) dissolving curcumin in MCT oil, stirring and dissolving for 1-4 h by using a magnetic stirrer, and fully dissolving by ultrasonic for 20min under the ultrasonic conditions of 20 kHz and 40% amplitude for 10 s, and stopping 5 s;

(10) and (3) mixing the solutions prepared in the steps (8) and (9) according to the weight ratio of 9: 1, and dispersing at 12000 rpm for 2 min to obtain a coarse emulsion;

(11) homogenizing the crude emulsion to obtain curcumin nanoemulsion with the final concentration of 0.2 mM; homogenizing under 20-30Mpa for 1-3 times;

(12) carrying out ultrahigh-temperature instantaneous sterilization treatment on the obtained curcumin nano emulsion under the sterilization conditions of 130-;

wherein the centrifugation conditions in the step (2), the step (3) and the step (4) are 5000-8000 g/min and 10-30 min.

2. The use of curcumin nanoemulsion prepared by the method of claim 1 in the preparation of fruit and vegetable preservatives.

3. Use of curcumin nanoemulsion prepared according to the method of claim 1 in the preparation of food bacteriostatic agents.

Technical Field

The invention belongs to the technical field of food processing, relates to curcumin nano-emulsion with a fresh-keeping effect, and also provides a preparation method of the curcumin nano-emulsion.

Background

The forest frog in northeast China is one of rare medicinal animals in China, is mainly produced in Changbai mountain areas in northeast China, and a large amount of forest frog eggs remained after the female frog takes oil are one of main byproducts in the production of the oviductus ranae. The research finds that the wood frog eggs contain a large amount of protein, and the protein is a good source of high-quality animal protein, and has a wide variety. Research proves that the woodfrog egg protein has physiological functions of fatigue resistance, aging resistance, oxidation resistance, anticancer activity and the like, and the low cost and large-scale yield make the woodfrog egg protein have important practical significance for development and utilization. Studies have reported that many proteins or protein hydrolysates are modified by glycosylation by maillard reactions to improve functional properties such as solubility.

Curcumin is a natural phenolic food additive extracted from the rhizome of the plant turmeric (turmeric), which is used in many countries as a flavor and food colorant. In recent years, curcumin has been proved to have anti-inflammatory and anticancer activities, and simultaneously has antibacterial activity on thalli such as staphylococcus aureus, escherichia coli, bacillus cereus, pseudomonas aeruginosa and the like after functionalization. The principle is that curcumin can induce a series of changes of bacteria under a certain concentration, including membrane depolarization and Ca²⁺The curcumin has antibacterial effect by inducing the generation of bacterial cell membrane, influencing the structure of the bacterial cell membrane and destroying the cell membrane, and is a natural and nontoxic food additive. However, the pure curcumin is limited in application due to poor solubility, low bioavailability and the like. Therefore, the colloidal preparation can be used for containing curcumin, so that the solubility and the stability of the curcumin are effectively increased, and the curcumin has slow release. The average particle size of the nano emulsion is usually less than 500 nm, the nano emulsion has the characteristics of good dynamic stability, low viscosity and the like, and the natural active product can be dissolved and protected by embedding curcumin in a nano emulsion system, so that the performance of the nano emulsion is not influenced by external factors, and the antibacterial action is better exertedThe purpose of food preservation is achieved.

Disclosed in the chinese patent gazette: 1. CN110973239A discloses a rot-proof preservative solution for grape fruits, a preparation method thereof and preservative paper, which comprise the following components in percentage by mass: 1.5 percent of chitosan, 1 percent of biological gelatin, 0.05 percent to 0.1 percent of citric acid, 1.5 percent to 3 percent of curcumin, 1.5 percent to 3 percent of chitosan oligosaccharide and the balance of water. The application takes biological gelatin and chitosan as film forming material carriers, fresh-keeping liquid components from biological sources are added and coated on paper, and the effective components are a mixture of chitosan, chitosan oligosaccharide, citric acid and curcumin. However, the invention does not consider the characteristic that curcumin is easy to decompose when exposed to light, and the system has no controlled release property. 2. CN110863354A discloses a multifunctional preservative film for meat products, which is prepared by taking a nano-fiber film as a substrate and loading an acidic polysaccharide-based ovalbumin film on the surface, wherein the preparation method comprises the steps of taking sodium alginate, carboxymethyl chitosan, polyethylene glycol, nano-bamboo fiber, bamboo leaf flavone, curcumin, polylysine and calcium gluconate as raw materials, obtaining the nano-fiber film by adopting an electrostatic spinning technology, and then loading the acidic polysaccharide-based ovalbumin on the nano-fiber film by adopting a layer-by-layer self-assembly technology, wherein the preservative film is yellow. The technology of the invention is complex, the cost is high, and the prepared preservative film has color and has adverse effect on the color of food.

Disclosure of Invention

The invention aims to provide a preparation method of curcumin nanoemulsion with a fresh-keeping effect, the embedding rate is more than 90%, the prepared product is uniform milk white, the smell is good, no fishy smell exists, the droplet size is between 300nm and 400nm, and the storage stability is good under a normal temperature environment.

The preparation method of the curcumin nano-emulsion with the fresh-keeping effect is realized by the following technical means:

(1) taking a proper amount of rana chensinensis eggs, drying for 2-4 h at 40-50 ℃, crushing and sieving with a 60-mesh sieve.

(2) Taking egg powder, using n-hexane to shake at constant temperature for 4 h for degreasing at the liquid-material ratio of 1:8 (g/mL) and the temperature of 40 ℃, centrifuging, repeatedly leaching for three times, and removing the leaching liquor.

(3) Mixing a certain amount of defatted rana japonica egg powder with water according to a ratio of 1: 8-20 (g/mL), adjusting pH to 11.0, adding activated carbon powder, stirring in a constant-temperature water bath at 50 ℃ for 60-120 min, and centrifuging to collect supernatant. The extraction was repeated twice and the supernatants were combined.

(4) Adjusting the pH value of the supernatant to 4.5, standing at 4 ℃ for 6-12 h, and centrifuging.

(5) And collecting the precipitate. Washing with 70% ethanol for 3 times, washing the precipitate with distilled water for 3 times, adjusting pH to 7.0 each time, and stirring to redissolve the precipitate. And (5) freeze-drying for 24-72 h to obtain the deodorized rana chensinensis egg protein powder.

(6) Preparing the wood frog egg protein solution and the xylose solution with the same mass concentration respectively, stirring and dissolving to ensure that the sample is fully hydrated. And mixing the protein solution and the sugar solution according to the volume ratio of 1: 0.5-2.

(7) And (3) adjusting the pH value of the solution prepared in the step (6) to 7, pouring the solution into a closed container, placing the container in a constant-temperature heating magnetic stirrer to react for 1-6 h at the temperature of 60-80 ℃, cooling to room temperature after the reaction is finished, centrifuging for 15min at 4000 g, and freeze-drying the supernatant to obtain glycosylated rana chensinensis egg protein powder.

(8) Dissolving the glycosylated rana chensinensis egg protein powder in distilled water to obtain a protein solution with the concentration of 1-5% (w/v). Stirring the protein solution at room temperature for 2-6 h, fully hydrating the protein solution, and adjusting the pH to =7 for later use.

(9) Dissolving curcumin in MCT oil, stirring and dissolving for 1-4 h by using a magnetic stirrer, and fully dissolving by ultrasonic for 20min under the ultrasonic conditions of 20 kHz and 40% amplitude for 10 s and stopping 5 s.

(10) And (3) mixing the solutions prepared in the steps (8) and (9) according to the weight ratio of 9: 1, and dispersing at 12000 rpm for 2 min to obtain a coarse emulsion.

(11) Homogenizing the crude emulsion to obtain curcumin nanoemulsion with final concentration of 0.2 mM. Homogenizing under 20-30Mpa for 1-3 times.

(12) And carrying out ultrahigh-temperature instantaneous sterilization treatment on the obtained curcumin nano emulsion under the sterilization conditions of 130-.

The centrifugation conditions in the step (2), the step (3) and the step (4) are 5000-8000 g/min and 10-30 min.

The curcumin nano-emulsion prepared by the method disclosed by the invention is applied to preparation of a fruit and vegetable preservative.

The curcumin nanoemulsion prepared by the method disclosed by the invention is applied to preparation of food bacteriostat.

The invention has the positive effects that:

the invention adopts the alkali-dissolving and acid-precipitating method to extract the woodfrog egg protein, the step of activated carbon adsorption is added in the dissolving process, so that the color of the supernatant of the dissolving solution is improved, and the precipitate obtained by washing the acid-precipitated product with ethanol effectively removes the fishy smell of the raw materials and improves the protein extraction rate. Then the woodfrog egg protein is modified by glycosylation, so that the solubility and the emulsibility are greatly improved, and then the modified woodfrog egg protein is used as an emulsifier to prepare the uniform and stable curcumin nano emulsion with the antibacterial and fresh-keeping effects. The invention considers the characteristics of difficult dissolution, unstable chemical property and easy decomposition by light of curcumin, and the curcumin is wrapped in an emulsion system by protein, thereby not only improving the solubility of the curcumin, but also ensuring the controlled release property of the system, so that the curcumin emulsion can play a long-term stable fresh-keeping and bacteriostatic action.

Detailed Description

The present invention is further illustrated by the following examples, which do not limit the present invention in any way, and any modifications or changes that can be easily made by a person skilled in the art to the present invention will fall within the scope of the claims of the present invention without departing from the technical solution of the present invention.

Example 1

(1) Taking a proper amount of wood frog eggs, drying for 2 hours at 40 ℃, crushing and sieving with a 60-mesh sieve;

(2) taking egg powder, using n-hexane to shake at constant temperature for 4 h and degreasing at the temperature of 40 ℃ according to the liquid-material ratio of 1:8 (g/mL), centrifuging for 15min at 5000r/min, repeatedly leaching for three times, and removing the leaching liquor;

(3) mixing a certain amount of defatted rana japonica egg powder with water at a ratio of 1:10 (g/mL), adjusting pH to 11.0, adding activated carbon powder, stirring in a 50 deg.C constant temperature water bath for 90min, centrifuging at 8000r/min for 20min, and collecting supernatant; extracting twice repeatedly, and mixing the supernatants;

(4) adjusting the pH value of the supernatant to 4.5, standing at 4 ℃ for 6h, and centrifuging;

(5) and collecting the precipitate. Washing with 70% ethanol for 3 times, washing the precipitate with distilled water for 3 times, adjusting pH to 7.0 each time, and stirring to redissolve the precipitate. Freeze-drying for 48 h to obtain deodorized ovum oviductus Ranae protein powder;

(6) preparing the wood frog egg protein solution and the xylose solution with the same mass concentration respectively, stirring and dissolving to ensure that the sample is fully hydrated. Mixing the protein solution and the sugar solution according to the volume ratio of 1: 0.5;

(7) adjusting the pH value of the solution prepared in the step (6) to 7, pouring the solution into a closed container, placing the container in a constant-temperature heating magnetic stirrer for reaction at 70 ℃ for 4 hours, cooling the solution to room temperature by using ice water bath treatment after the reaction is finished, centrifuging the solution for 15 minutes at 4000 g, and cooling and freeze-drying the supernatant to obtain glycosylated rana chensinensis egg protein powder;

(8) dissolving glycosylated oviductus ranae albumen powder in distilled water to obtain a protein solution with the concentration of 3% (w/v). Stirring the protein solution at room temperature for 4 h, fully hydrating the protein solution, and adjusting the pH to =7 for later use;

(9) dissolving curcumin in MCT oil, stirring and dissolving for 2 h by a magnetic stirrer, and performing ultrasonic treatment for 20min for sufficient dissolution, wherein the ultrasonic treatment condition is 20 kHz and 40% amplitude, the ultrasonic treatment is performed for 10 s, and the ultrasonic treatment is stopped for 5 s;

(10) and (3) mixing the solutions prepared in the steps (8) and (9) according to the weight ratio of 9: 1, and dispersing at 12000 rpm for 2 min to obtain a coarse emulsion;

(11) homogenizing the crude emulsion under 20 Mpa for 3 times;

(12) the obtained curcumin nano emulsion is subjected to ultrahigh temperature instantaneous sterilization treatment, wherein the sterilization conditions are 130 ℃ and 5 s. The obtained nano emulsion has final curcumin concentration of 0.2 mM, protein concentration of 3%, uniform milky white product, light coconut flavor and curcumin flavor, and no fishy smell.

Example 2

(1) Taking a proper amount of rana chensinensis eggs, drying for 3 hours at 40 ℃, crushing and sieving with a 60-mesh sieve;

(2) taking egg powder, using n-hexane to shake at constant temperature for 4 h and degreasing at the temperature of 40 ℃ according to the liquid-material ratio of 1:8 (g/mL), centrifuging for 15min at 5000r/min, repeatedly leaching for three times, and removing the leaching liquor;

(3) mixing a certain amount of defatted rana japonica egg powder with water at a ratio of 1:20 (g/mL), adjusting pH to 11.0, adding activated carbon powder, stirring in a constant temperature water bath at 50 deg.C for 90min, centrifuging at 8000r/min for 20min, and collecting supernatant. Extracting twice repeatedly, and mixing the supernatants;

(4) adjusting the pH value of the supernatant to 4.5, standing at 4 ℃ for 12 h, and centrifuging;

(5) and collecting the precipitate. Washing with 70% ethanol for 3 times, washing the precipitate with distilled water for 3 times, adjusting pH to 7.0 each time, and stirring to redissolve the precipitate. Freeze-drying for 72 h to obtain deodorized ovum oviductus Ranae protein powder;

(6) preparing the wood frog egg protein solution and the xylose solution with the same mass concentration respectively, stirring and dissolving to ensure that the sample is fully hydrated. Mixing the protein solution and the sugar solution according to the volume ratio of 1: 1;

(7) adjusting the pH value of the solution prepared in the step (6) to 7, pouring the solution into a closed container, placing the container in a constant-temperature heating magnetic stirrer for reaction at 60 ℃ for 6 hours, cooling the solution to room temperature by using ice water bath treatment after the reaction is finished, centrifuging the solution for 15 minutes at 4000 g, and cooling and freeze-drying the supernatant to obtain glycosylated rana chensinensis egg protein powder;

(8) dissolving glycosylated oviductus ranae albumen powder in distilled water to obtain a protein solution with the concentration of 3% (w/v). Stirring the protein solution at room temperature for 4 h, fully hydrating the protein solution, and adjusting the pH to =7 for later use;

(9) dissolving curcumin in MCT oil, stirring and dissolving for 2 h by a magnetic stirrer, and performing ultrasonic treatment for 20min for sufficient dissolution, wherein the ultrasonic treatment condition is 20 kHz and 40% amplitude, the ultrasonic treatment is performed for 10 s, and the ultrasonic treatment is stopped for 5 s;

(10) and (3) mixing the solutions prepared in the steps (8) and (9) according to the weight ratio of 9: 1, and dispersing at 12000 rpm for 2 min to obtain a coarse emulsion;

(11) homogenizing the crude emulsion under 30Mpa for 2 times;

(12) the obtained curcumin nano emulsion is subjected to ultrahigh temperature instantaneous sterilization treatment, wherein the sterilization conditions are 130 ℃ and 5 s. The obtained nano emulsion with curcumin final concentration of 0.2 mM has protein concentration of 3%, and the product is uniform milky white, has light coconut fragrance and curcumin fragrance, and has no fishy smell and slightly sweet taste.

Example 3

(1) Taking a proper amount of rana chensinensis eggs, drying for 4 hours at 40 ℃, crushing and sieving with a 60-mesh sieve;

(2) taking egg powder, using n-hexane to shake at constant temperature for 4 h and degreasing at the temperature of 40 ℃ according to the liquid-material ratio of 1:8 (g/mL), centrifuging for 15min at 5000r/min, repeatedly leaching for three times, and removing the leaching liquor;

(3) mixing a certain amount of defatted rana japonica egg powder with water at a ratio of 1:20 (g/mL), adjusting pH to 11.0, adding activated carbon powder, stirring in a constant temperature water bath at 50 deg.C for 120min, centrifuging at 8000r/min for 20min, and collecting supernatant. Extracting twice repeatedly, and mixing the supernatants;

(4) adjusting the pH value of the supernatant to 4.5, standing at 4 ℃ for 12 h, and centrifuging;

(5) and collecting the precipitate. Washing with 70% ethanol for 3 times, washing the precipitate with distilled water for 3 times, adjusting pH to 7.0 each time, and stirring to redissolve the precipitate. Freeze-drying for 72 h to obtain deodorized ovum oviductus Ranae protein powder;

(6) preparing a wood frog egg protein solution and a xylose solution with the same mass concentration respectively, stirring and dissolving to ensure that a sample is fully hydrated; mixing the protein solution and the sugar solution according to the volume ratio of 1: 2;

(7) adjusting the pH value of the solution prepared in the step (6) to 7, pouring the solution into a closed container, placing the container in a constant-temperature heating magnetic stirrer for reaction at the temperature of 80 ℃ for 3 hours, cooling the solution to room temperature by using ice water bath treatment after the reaction is finished, centrifuging the solution for 15 minutes at the speed of 4000 g, and performing freeze drying on the supernatant to obtain glycosylated rana chensinensis egg protein powder;

(8) dissolving glycosylated wood frog egg protein powder in distilled water to obtain protein solution with concentration of 5% (w/v). Stirring the protein solution at room temperature for 4 h, fully hydrating the protein solution, and adjusting the pH to =7 for later use;

(9) dissolving curcumin in MCT oil, stirring with a magnetic stirrer for 2 hr, and ultrasonic treating at 20 kHz and 40% amplitude for 10 s for 5s for 20 min.

(10) And (3) mixing the solutions prepared in the steps (8) and (9) according to the weight ratio of 9: 1, and dispersing at 12000 rpm for 2 min to obtain a coarse emulsion;

(11) homogenizing the crude emulsion under 20 Mpa for 3 times;

(12) the obtained curcumin nano emulsion is subjected to ultrahigh temperature instantaneous sterilization treatment under the sterilization conditions of 140 ℃ for 3 s. The obtained nano emulsion has curcumin final concentration of 0.2 mM, protein concentration of 5%, uniform milky white product, light coconut fragrance and curcumin fragrance, no fishy smell, and slightly sweet taste.

The effects of the invention on the fresh-keeping and bacteriostasis of fruits and vegetables are proved by the following test examples:

test example 1

The curcumin nano-emulsion prepared in the embodiment 1-embodiment 3 is taken, and the fresh-keeping effect of the curcumin nano-emulsion is verified by taking the satay orange as an example. Selecting high-quality fresh Shatang orange fruits, dividing one group into two groups, uniformly spraying curcumin emulsion on the surface of the other group, and after the surface moisture is dried, putting the two groups of fruits into a fresh-keeping chamber for storage for 60 days. And (3) measuring indexes such as rotten fruit rate, weight loss rate, soluble solid content and the like after storage, and finding that the indexes of a sample group sprayed with the curcumin emulsion are superior to those of an untreated group in all aspects. Wherein the rotten fruit rate is about 10 percent lower than that of the untreated group, the weight loss rate is about 2 percent lower than that of the untreated group, and the fresh-keeping effect is obvious.

And (4) conclusion:

the invention adopts an alkali dissolution method to extract the rana chensinensis egg protein, the method is simple and easy to operate, the color of the product is improved by adding the active carbon, the original fishy smell of the raw material is effectively removed by washing with the ethanol, the obtained rana chensinensis egg protein is yellow brown powder and has light salty and fishy smell, and the extraction rate reaches 50 percent. The functional characteristics of the woodfrog egg protein are improved by a glycosylation means, and experiments prove that the solubility of the woodfrog egg protein is improved by about 2 times of the original solubility at the same temperature, which is close to 100%; the emulsibility is improved by 4 times. Then the protein after sugar is used as an emulsifier to prepare the uniform and stable curcumin nano-emulsion preservative. The final product obtained by the invention is milk white, has light coconut smell and curcumin smell, and has no peculiar smell or fishy smell. The covalent binding reaction with xylose improves the solubility and emulsification property of the wood frog egg protein, so that the wood frog egg protein plays a better stabilizing role in an emulsion system, the embedding rate of curcumin reaches more than 90 percent, and the wood frog egg protein is stable when stored for more than one month in a normal temperature environment. Due to the coating of protein, curcumin is dissolved in an emulsion system, the stability of curcumin is improved, the antioxidant and antibacterial properties of curcumin are kept, the curcumin is slowly released in the storage process, the effects of preservation and sterilization are exerted, the curcumin embedding amount in the emulsion is about 50-60% after one month, and the controlled release effect is good. The curcumin emulsion preservative can be sprayed on the surfaces of fruits and vegetables picked in a large scale, or the picked fruits and vegetables are immersed in the curcumin emulsion for a few minutes, so that the preservation time of the fresh fruits and vegetables is prolonged, and the rotten rate and the weight loss rate of the fruits treated by the curcumin emulsion preservative are lower than those of the fruits treated by the non-treatment group under the same storage condition. The method is simple, convenient and low in cost, safe, nontoxic and pollution-free, and has good market prospect.