1-methylcyclopropene stable emulsifier and preparation method thereof

Abstract

The invention relates to the technical field of fruit and vegetable preservatives, and discloses a 1-methylcyclopropene stable emulsifier and a preparation method thereof, the 1-methylcyclopropene stable emulsifier comprises the following raw materials by mass: 0.01-15% of an active component; 0.2 to 6% of a surfactant; 0.1 to 1.5 percent of a stabilizing agent; 35 to 60 percent of eutectic solution; 37.9 to 49 percent of an oil phase; and the active component is 1-methylcyclopropene. The stable 1-methylcyclopropene emulsion product obtained by the invention has the advantages of high 1-methylcyclopropene effective component content, good stability, low toxicity, low cost and easiness in preparation.

Description

Technical Field

[0001] The invention relates to the technical field of fruit and vegetable preservatives, in particular to a 1-methylcyclopropene stabilized emulsifier and a preparation method thereof. Background Art

[0002] 1-Methylcyclopropene (1-MCP) is a highly effective preservative for fruits and vegetables. It can delay the post-harvest aging of fruits and flowers, prolong the storage time of fruits and flowers, and has a certain impact on fruit flavor and post-harvest diseases. However, 1-MCP is gaseous at room temperature and pressure, and is not easy to store and transport, which greatly limits its application and promotion. At present, the existing methods for solving the storage and use of 1-MCP include solid reagent inclusion, low temperature stability, coating film solidification, and the solidified 1-MCP inclusion compound is made into emulsion, etc. For example, the disclosed solidification method of 1-MCP is to use cyclodextrin to encapsulate and solidify it, but due to the limited volume of the cavity that can be used for the inclusion of cyclodextrin molecules, the effective content of 1-MCP in the obtained solid inclusion compound generally does not exceed 4%; low-temperature stability generally requires the use of low-boiling point liquids, which is not conducive to the storage, transportation and use of 1-MCP; the solidified 1-methylcyclopropene inclusion compound is made into an emulsion again, which is to use water, salt and organic solvents to treat the 1-methylcyclopropene inclusion compound to prepare a water-in-oil-in-water emulsion 1-MCP preservative, but its preparation process is complicated, the effective content of 1-MCP is low, and it is not conducive to the use of 1-MCP and the precise control of the concentration. Summary of the invention

[0003] The invention provides a 1-methylcyclopropene stabilized emulsifier and a preparation method thereof, which solves the problems of complicated preparation process and inconvenient storage and transportation in the prior art.

[0004] The scheme of the present invention is:

[0005] A 1-methylcyclopropene stabilized emulsifier comprises the following raw materials in percentage by weight:

[0006]

[0007] The active component is 1-methylcyclopropene.

[0008] As a preferred technical solution, the eutectic solution is a eutectic solution formed by a binary solvent of a hydrogen bond donor and a hydrogen bond acceptor, wherein the hydrogen bond donor is one or more of ethylene glycol, propylene glycol, urea, acetic acid, and oxalic acid; and the hydrogen bond acceptor is one or more of choline chloride, dodecyltrimethylammonium chloride, trimethylethylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, and benzyltrimethylammonium hydroxide.

[0009] As a preferred technical solution, the surfactant is a nonionic surfactant, and the surfactant is one or more of alkyl alcohol polyoxyethylene ether, polyoxyethylene fatty alcohol ether, Span 80, and Tween 80.

[0010] As a preferred technical solution, the stabilizer is one of sodium carboxymethyl cellulose or hydroxyethyl cellulose.

[0011] As a preferred technical solution, the oil phase substance is one or more of rapeseed oil, peanut oil, olive oil, and liquid paraffin oil.

[0012] The present invention also discloses a method for preparing a 1-methylcyclopropene stabilized emulsifier, which is characterized by comprising the following steps:

[0013] 1) mixing a hydrogen bond donor and a hydrogen bond acceptor at a temperature of 45 to 50° C. to obtain a clear and transparent eutectic solution, dissolving 0.2 to 6% of a surfactant and 0.1 to 1.5% of a stabilizer in 35 to 60% of the eutectic solution to prepare a eutectic solution containing a surfactant and a stabilizer;

[0014] 2) introducing 0.01-15% of an active ingredient into the eutectic solution containing a surfactant and a stabilizer obtained in step 1) under stirring, wherein the active ingredient is 1-methylcyclopropene gas, and stirring after the 1-methylcyclopropene gas is completely dissolved and absorbed to form a liquid phase 1-methylcyclopropene eutectic solution;

[0015] 3) Slowly add the liquid 1-methylcyclopropene eutectic solution to 37.9-49% of the oil phase at a temperature of -5-5°C and under rapid stirring, and stir to obtain a 1-methylcyclopropene stable emulsifier, which is sealed and stored for later use.

[0016] As a preferred technical solution, in the step 3), the stirring time after the 1-methylcyclopropene eutectic solution in the liquid phase is added to the oil phase is 3 to 8 hours.

[0017] As a preferred technical solution, the storage temperature in 3) is ≤25°C.

[0018] As a preferred technical solution, the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor in 1) is 1:1-2.

[0019] Advantages of the present invention:

[0020] The 1-methylcyclopropene stabilized emulsifier of the present invention mainly dissolves and stabilizes 1-methylcyclopropene gas through a eutectic solvent containing a surfactant and a stabilizer, and then the oil phase stabilizes the obtained eutectic solution containing 1-methylcyclopropene, so that the eutectic solution containing 1-methylcyclopropene forms very small stable vesicles in the oil and fat, and further stabilizes the eutectic solution. Finally, the 1-methylcyclopropene stabilized emulsifier is formed, and the stable emulsion is very stable below 25° C., but can slowly release 1-methylcyclopropene gas at a higher temperature or in an aqueous solution.

[0021] The 1-methylcyclopropene stabilized emulsifier provided by the present invention and the preparation method thereof can adjust the content of the active component 1-methylcyclopropene component in the 1-methylcyclopropene stabilized emulsifier according to demand, with a wide adjustment range, and is relatively stable under normal temperature and low temperature conditions, and can continuously release 1-methylcyclopropene in a high temperature environment or water, thereby effectively preserving fruits and vegetables. At the same time, the preparation method is simple, the raw materials used are environmentally friendly and non-toxic, and the 1-methylcyclopropene stabilized emulsifier is suitable for large-scale production and promotion. DETAILED DESCRIPTION

[0022] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments.

[0023] Example 1

[0024] A 1-methylcyclopropene stabilized emulsifier, comprising 1-methylcyclopropene as an active ingredient, a eutectic solution containing a surfactant and a stabilizer as a solvent, and dispersed in an oil phase. The weight ratio of 1-methylcyclopropene, eutectic solution, surfactant, stabilizer and oil phase material is 15:35:6:2:42 respectively, and the specific preparation method is as follows:

[0025] 1) Urea as a hydrogen bond donor and choline chloride as a hydrogen bond acceptor were added into a reactor in a molar ratio of 1:1 and stirred at 50° C. for 2 h to form a completely transparent eutectic solution, which was then cooled to room temperature.

[0026] 2) adding the eutectic solution obtained in step 1), Span 80 and sodium carboxymethyl cellulose in a weight ratio of 35:6:2 at room temperature, and stirring at room temperature to form a uniform eutectic solution.

[0027] 3) Slowly introduce 1-methylcyclopropene gas into the eutectic solution of step 2) at a weight ratio of 15:43 at room temperature and under stirring conditions. After the 1-methylcyclopropene gas is completely dissolved and absorbed, stir for another 3 hours to form a eutectic solution of 1-methylcyclopropene;

[0028] 4) Slowly add the obtained 1-methylcyclopropene eutectic solution into olive oil at a weight ratio of 58:42 at 5° C. and stir rapidly for 5 hours to obtain a stable 1-methylcyclopropene emulsion. After sealing, store at below 10° C. for later use.

[0029] Example 2

[0030] A stable 1-methylcyclopropene emulsifier, comprising 1-methylcyclopropene as an active ingredient, a eutectic solution containing a surfactant and a stabilizer as a solvent, and dispersed in an oil phase. The weight ratios of 1-methylcyclopropene, eutectic solution, surfactant, stabilizer and oil phase material are 5:50:3:1:41, respectively. The specific preparation method is as follows:

[0031] 1) Add glycerol as a hydrogen bond donor and benzyltrimethylammonium hydroxide as a hydrogen bond acceptor into a reactor in a molar ratio of 1:2 and stir at 50° C. for 2 h to form a completely transparent eutectic, and then cool to room temperature.

[0032] 2) At room temperature, the eutectic solution obtained in step 1), betaine and hydroxyethyl cellulose were added in a weight ratio of 50:3:1, and stirred at room temperature to form a uniform eutectic solution.

[0033] 3) Slowly introduce 1-methylcyclopropene gas into the eutectic solution of step 2) at a weight ratio of 5:54 at room temperature and under stirring conditions. After the 1-methylcyclopropene gas is completely dissolved and absorbed, stir for another 3.5 hours to form a eutectic solution of 1-methylcyclopropene;

[0034] 4) Slowly add the obtained 1-methylcyclopropene eutectic solution into liquid paraffin oil at a weight ratio of 59:41 at 0°C and rapid stirring, and stir for 5 hours to obtain a stable 1-methylcyclopropene emulsion. After sealing, store at below 10°C for later use.

[0035] Example 3

[0036] A stable 1-methylcyclopropene emulsifier, comprising 1-methylcyclopropene as an active ingredient, a eutectic solution containing a surfactant and a stabilizer as a solvent, and dispersed in an oil phase. The weight ratios of 1-methylcyclopropene, eutectic solution, surfactant, stabilizer and oil phase material are 1:60:1:0.5:37.5 respectively, and the specific preparation method is as follows:

[0037] 1) Oxalic acid as a hydrogen bond donor and trimethylethylammonium hydroxide as a hydrogen bond acceptor were added into a reactor in a molar ratio of 1:1 and stirred at 50° C. for 2 h to form a completely transparent eutectic, and then cooled to room temperature.

[0038] 2) adding the eutectic solution obtained in step 1), alkyl alcohol polyoxyethylene ether and carboxyhydroxyethyl cellulose at a weight ratio of 60:1:0.5 at room temperature, and stirring at room temperature to form a uniform eutectic solution.

[0039] 3) Slowly introduce 1-methylcyclopropene gas into the eutectic solution of step 2) at a weight ratio of 1:61.5 at room temperature and under stirring conditions. After the 1-methylcyclopropene gas is completely dissolved and absorbed, stir for another 5 hours to form a eutectic solution of 1-methylcyclopropene;

[0040] 4) Slowly add the obtained 1-methylcyclopropene eutectic solution to the oil phase material peanut oil at a weight ratio of 62.5:37.5 at -5°C and rapid stirring, and stir for 8 hours to obtain a stable 1-methylcyclopropene emulsion. After sealing, store at below 10°C for use.

[0041] Example 4

[0042] A stable 1-methylcyclopropene emulsifier, comprising 1-methylcyclopropene as an active ingredient, a eutectic solution containing a surfactant and a stabilizer as a solvent, and dispersed in an oil phase. The weight ratio of 1-methylcyclopropene, eutectic solution, surfactant, stabilizer and oil phase material is 0.1:50:0.7:0.2:49 respectively, and the specific preparation method is as follows:

[0043] 1) Add hydrogen bond donor acetic acid and hydrogen bond acceptor tetraethylammonium hydroxide in a molar ratio of 1:2 into a reactor and stir at 50° C. for 2 h to form a completely transparent eutectic, and then cool to room temperature.

[0044] 2) adding the eutectic solution obtained in step 1), polyoxyethylene fatty alcohol ether and sodium carboxymethyl cellulose in a weight ratio of 50:0.7:0.2 at room temperature, and stirring at room temperature to form a uniform eutectic solution.

[0045] 3) Slowly introduce 1-methylcyclopropene gas into the eutectic solution of step 2) at a weight ratio of 0.1:50.9 at room temperature and under stirring conditions. After the 1-methylcyclopropene gas is completely dissolved and absorbed, stir for another 8 hours to form a eutectic solution of 1-methylcyclopropene;

[0046] 4) Slowly add the obtained 1-methylcyclopropene eutectic solution into rapeseed oil at a weight ratio of 51:49 at -5°C and rapid stirring, and stir for 6 hours to obtain a stable 1-methylcyclopropene emulsion. After sealing, store at below 10°C for later use.

[0047] Example 5

[0048] A stable 1-methylcyclopropene emulsifier, comprising 1-methylcyclopropene as an active ingredient, a eutectic solution containing a surfactant and a stabilizer as a solvent, and dispersed in an oil phase. The weight ratio of 1-methylcyclopropene, eutectic solution, surfactant, stabilizer and oil phase material is 0.01:59:0.2:0.79:40 respectively, and the specific preparation method is as follows:

[0049] 1) Add hydrogen bond donor ethylene glycol and hydrogen bond acceptor tetramethylammonium hydroxide in a molar ratio of 2:1 into a reactor and stir at 50° C. for 2 h to form a completely transparent eutectic, and then cool to room temperature.

[0050] 2) At room temperature, the eutectic solvent obtained in step 1), Span 80 and sodium carboxymethyl cellulose were added in a weight ratio of 59:0.2:0.79, and stirred at room temperature to form a uniform eutectic solution.

[0051] 3) At room temperature and under stirring conditions, 1-methylcyclopropene gas is slowly introduced into the eutectic solution of step 2) at a weight ratio of 0.01:59.99. After the 1-methylcyclopropene gas is completely dissolved and absorbed, stirring is continued for 3 hours to form a eutectic solution of 1-methylcyclopropene;

[0052] 4) Slowly add the obtained 1-methylcyclopropene eutectic solution into rapeseed oil at a weight ratio of 60:40 at 5° C. and with rapid stirring, and stir for 4 hours to obtain a stable 1-methylcyclopropene emulsion. After sealing, store at below 10° C. for later use.

[0053] 10.0 g of the 1-methylcyclopropene stable emulsions obtained in Examples 1, 2, 3, 4 and 5 were respectively placed in glass bottles sealed with 100 mL silica gel caps, and placed in a constant temperature oven at 35° C. The gas above the glass bottles was extracted every 5 days, and the release rates of the active component 1-methylcyclopropene of the five products were tested by gas chromatography. The specific data are shown in Table 1:

[0054] Table 1

[0055]

[0056] It can be seen from the data in Table 1 that the stable 1-methylcyclopropene emulsion obtained by the present invention exhibits good stability at 35° C. Even after being stored for 30 days, the active component 1-methylcyclopropene therein is only released and lost by less than 2%. This indicates that the liquid 1-methylcyclopropene emulsifier obtained by the present invention is very stable even at a relatively high temperature, and the 1-methylcyclopropene therein has good stability, which is beneficial to its long-term preservation of fruits and vegetables.

[0057] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A 1-methylcyclopropene stabilized emulsifier, characterized in that The following raw materials are included in mass percentage: The active component is 1-methylcyclopropene.

2. A 1-methylcyclopropene stabilized emulsifier as claimed in claim 1, characterized in that: The eutectic solution is a eutectic solution formed by a binary solvent of a hydrogen bond donor and a hydrogen bond acceptor, wherein the hydrogen bond donor is one or more of ethylene glycol, propylene glycol, urea, acetic acid, and oxalic acid; and the hydrogen bond acceptor is one or more of choline chloride, dodecyltrimethylammonium chloride, trimethylethylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, and benzyltrimethylammonium hydroxide.

3. A 1-methylcyclopropene stabilized emulsifier as claimed in claim 1, characterized in that: The surfactant is one or more of alkyl alcohol polyoxyethylene ether, polyoxyethylene fatty alcohol ether, Span 80, and Tween 80.

4. A 1-methylcyclopropene stabilized emulsifier as claimed in claim 1, characterized in that: The stabilizer is one of sodium carboxymethyl cellulose or hydroxyethyl cellulose.

5. A 1-methylcyclopropene stabilized emulsifier as claimed in claim 1, characterized in that: The oil phase material is one or more of rapeseed oil, peanut oil, olive oil and liquid paraffin oil.

6. A method for preparing the 1-methylcyclopropene stabilized emulsifier according to any one of claims 1 to 5, characterized in that: The following steps are involved: 1) mixing a hydrogen bond donor and a hydrogen bond acceptor at a temperature of 45 to 50° C. to obtain a clear and transparent eutectic solution, dissolving 0.2 to 6% of a surfactant and 0.1 to 1.5% of a stabilizer in 35 to 60% of the eutectic solvent to prepare a eutectic solution containing the surfactant and the stabilizer; 2) introducing 0.01-15% of an active ingredient into the eutectic solution containing a surfactant and a stabilizer obtained in step 1) under stirring, wherein the active ingredient is 1-methylcyclopropene gas, and stirring after the 1-methylcyclopropene gas is completely dissolved and absorbed to form a liquid phase 1-methylcyclopropene eutectic solution; 3) Slowly add the liquid 1-methylcyclopropene eutectic solution to 37.9-49% of the oil phase at a temperature of -5-5°C and under rapid stirring, and stir to obtain a 1-methylcyclopropene stable emulsifier, which is sealed and stored for later use.

7. A method for preparing a 1-methylcyclopropene stabilized emulsifier as claimed in claim 6, characterized in that: The stirring time after the 1-methylcyclopropene eutectic solution in the liquid phase in step 3) is added to the oil phase is 3 to 8 hours.

8. A method for preparing a 1-methylcyclopropene stabilized emulsifier as claimed in claim 6, characterized in that: The storage temperature in 3) is ≤25°C.

9. A method for preparing a 1-methylcyclopropene stabilized emulsifier as claimed in claim 6, characterized in that: The molar ratio of the hydrogen bond donor to the hydrogen bond acceptor in 1) is 1:1-2.

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