CN1231277A - Fat-soluble tea polyphenol and esterfication method productive process thereof - Google Patents

Abstract

A production process of powdery fat-soluble tea polyphenols and its esterification method. Water-soluble tea polyphenols are used as raw materials, inert organic solvents are used as dissolving and diluents, and under the action of a special esterification catalyst, the temperature of the reaction system is controlled at Between 0°C and the reflux temperature of the organic solvent, add a solubilizer in a weight ratio of 1:0.5 to 10 based on tea polyphenols, undergo esterification, filter, wash with water, concentrate under reduced pressure, and recrystallize to remove catalysts, organic solvents, and The by-products are then dehydrated and dried to obtain powdered fat-soluble tea polyphenols. This product has obvious anti-oxidative and quality-preserving effects on heavy oil foods and edible oils, without any toxic and side effects, can maintain the original quality of oil products, and can increase the transparency and brightness of oil products. Adding 100-200ppm can significantly improve the quality of oil products. The shelf life of oil products is more than one and a half years.

Description

Fat-soluble tea polyphenol and its production method by esterification

The invention relates to the technical field of a fat-soluble tea polyphenol and its esterification production method.

At present, the commonly used oil antioxidants at home and abroad include BHA, BHT, TBHQ, etc. It is well known that synthetic antioxidants will bring some toxic and side effects to a greater or lesser extent. Therefore, the development and research of fat-soluble tea polyphenols instead of synthetic antioxidants has attracted more and more attention and attention. Over the years, some tertiary institutions, scientific research institutes, and industrial and mining enterprises dedicated to the deep processing of tea have successively carried out research and development on the fat solubility of water-soluble tea polyphenols. Food Science", 17(5), 1996, the fat-soluble tea polyphenols produced by this method are actually a compound of water-soluble tea polyphenols and emulsifiers, and the appearance is liquid or paste, and the emulsifiers are generally Polyethylene glycol polyether compounds are used. Although the presence of emulsifiers can improve the fat-solubility of tea polyphenols to a certain extent, the stability of dissolution has not always achieved the desired effect, and even precipitated due to demulsification. The only domestic patent CN1197786A reports that although it is fat-soluble, it is a viscous oil, which is not only basically the same as the appearance prepared by the emulsification method, but also cannot control the condensation of "red powder" during the reaction process due to the strong acidic environment of the reaction system. This will greatly affect the antioxidant effect of the product.

The first object of the present invention is to provide a powdery fat-soluble tea polyphenol which can be dissolved in oil and has relatively pure quality.

The second object of the present invention is to provide a method for producing the above-mentioned fat-soluble tea polyphenols by esterification.

The technical solution for realizing the first purpose of the present invention is as follows. The fat-soluble tea polyphenol is made of water-soluble tea polyphenol as a raw material, and an inert organic solvent is used as a dissolving and diluent. Under the action of an esterification catalyst, the temperature of the reaction system is controlled between 0°C and the reflux temperature of the organic solvent, and A solubilizer in a weight ratio of 1:0.5 to 10 in terms of tea polyphenols is subjected to esterification, filtration, water washing, concentration under reduced pressure, recrystallization, and then dehydration and drying into a slightly yellow to khaki powder that is insoluble in water. Solid soluble in acetone, ethanol and water-insoluble solvents.

Above-mentioned inert organic solvent is ethyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl butyrate, ether, tetrahydrofuran, ethylene glycol dimethyl ether, acetone, cyclohexanone, methyl isobutyl ketone, N , any one of N-dimethylformamide (DMF), N-N-dimethylacetamide (DMAC), hexamethylphosphoric triamide (HMPA), and petroleum ether or mixed in any proportion. The best one can be any one of ethyl acetate, tetrahydrofuran, and N,N-dimethylformamide (DMF).

Above-mentioned esterification catalyst can be any one in potassium carbonate, potassium bicarbonate, sodium carbonate, sodium bicarbonate, triethylamine, pyridine, butyl titanate, magnesium, copper, aluminum, zinc, iron, nickel, tin. Optimally, it can be any one of sodium carbonate, pyridine, triethylamine, and metallic magnesium.

The above-mentioned solubilizing agent refers to any one of organic saturated or unsaturated fatty acid chlorides or corresponding acid anhydride derivatives containing 12 to 32 carbon atoms or any mixture in any proportion. The best choice may be organic saturated fatty acid chlorides containing 16-22 carbon atoms.

The temperature of the above reaction system is optimally selected at 25-45°C.

The technical solution for realizing the second object of the present invention is as follows. Use natural water-soluble tea polyphenols as raw materials, inert organic solvents as dissolving and diluents, in the presence of an esterification catalyst, control the temperature of the reaction body between 0°C and the reflux temperature of the organic solvent, and add tea polyphenol juice 1: A solubilizer with a weight ratio of 0.5 to 10 is used to synthesize fat-soluble tea polyphenols through esterification; the reaction solution is filtered, washed with water, concentrated under reduced pressure, recrystallized, and catalysts, organic solvents and by-products are removed, and then dehydrated and dried to light yellow to earthy The yellow powdery solid is the product.

The powdery fat-soluble tea polyphenols of the present invention have obvious anti-oxidative and quality-preserving effects on heavy oil foods and edible oils, without any toxic and side effects, can maintain the original quality of oil products, and can increase the transparency and brightness of oil products. The addition amount is 100 ~200PPm, it can significantly prolong the shelf life of the oil for more than one and a half years. In the production method provided by the invention, because of the presence of a catalyst, the reaction of the system is mild, the yield of the product is improved, the reaction can be further completed, the final product has high stability, and the amount of by-products is small.

The embodiments of the present invention will be further described in detail below.

Embodiment 1. Take water-soluble tea polyphenol 60, dissolve it in 600 grams of ethyl acetate, add 50 grams of pyridine, heat to 30°C, add 55 grams of palmitoyl chloride dropwise within three hours, and continue to keep warm for 8 hours. At this time, the reaction solution should be clear liquid. After stopping the reaction, filter, wash the filtrate with water, concentrate under reduced pressure, recrystallize, and then dehydrate and dry to obtain slightly yellow powdery fat-soluble tea polyphenols.

Embodiment 2. Take 600 grams of water-soluble tea polyphenols, dissolve them in 700 grams of tetrahydrofuran, add 80 grams of sodium carbonate, heat to 45°C, add 120 grams of behenic acid chloride dropwise, and keep warm until no gas is released during the reaction. After stopping the reaction, filter, wash the filtrate with water, concentrate under reduced pressure, recrystallize, and then dehydrate and dry to obtain slightly yellow powdery fat-soluble tea polyphenols.

Embodiment 3. Take 40 grams of water-soluble tea polyphenols, dissolve in 20 grams of ethyl acetate, add 20 grams of metal magnesium, heat to 25 ° C, dropwise add 50 grams of palmitoyl chloride and stearyl chloride mixture (wherein palmitoyl chloride accounts for about 35%, stearic acid Acyl chloride accounts for about 65%). When the pH value of the reaction solution is 2-4, the reaction can be stopped when the heat preservation reaction is performed. At this time, the reaction solution should be a transparent liquid. After stopping the reaction, filter, wash the filtrate with water, concentrate under reduced pressure, recrystallize, and then dehydrate and dry to obtain about 72 grams of khaki powdery solid.

Embodiment 4. Take 60 grams of water-soluble tea polyphenols, dissolve them in 600 grams of N,N-dimethylformamide (DMF), add 20 grams of triethylamine, heat to 30°C, and drop 60 grams of stearyl chloride in five hours. Continue to insulate and react for 8 hours, and the solution should be a transparent liquid when the reaction finishes. Then the reaction solution was filtered, washed with water, concentrated under reduced pressure, recrystallized, dehydrated and dried, and finally about 93 grams of a light yellow powdery solid product could be obtained.

Claims (7)

1. fat-soluble tea polyphenol, it is characterized in that with the water soluble tea polyphenol being raw material, inert organic solvents is dissolving, thinner, under the esterifying catalyst effect, control temperature of reaction system at 0 ℃ between the reflux temperature of organic solvent, adding is in the solubilizing agent of tea-polyphenol 1: 0.5～10 part by weight, through esterification, filtration, washing, concentrating under reduced pressure, recrystallization, dehydrate then Cheng Weihuang to khaki, be powdery, water insoluble and be soluble in solid in acetone, ethanol and the water-insoluble solvent.

2. fat-soluble tea polyphenol as claimed in claim 1, it is characterized in that described inert organic solvents is ethyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl butyrate, ether, tetrahydrofuran (THF), glycol dimethyl ether, acetone, pimelinketone, mibk, N, dinethylformamide (DMF), N-N-N,N-DIMETHYLACETAMIDE (DMAC), any in HMPA (HMPA), the sherwood oil or arbitrary proportion mix.

3. fat-soluble tea polyphenol as claimed in claim 1 is characterized in that inert organic solvents the best can be ethyl acetate, tetrahydrofuran (THF), N, any one in the dinethylformamide (DMF).

4. fat-soluble tea polyphenol as claimed in claim 1 is characterized in that described esterifying catalyst can be any in salt of wormwood, saleratus, yellow soda ash, sodium bicarbonate, triethylamine, pyridine, butyl (tetra) titanate, magnesium, copper, aluminium, zinc, iron, nickel, the tin.

5. as claim 1 or 4 described fat-soluble tea polyphenols, it is characterized in that described esterifying catalyst the best can be any in yellow soda ash, pyridine, triethylamine, the MAGNESIUM METAL.

6. fat-soluble tea polyphenol as claimed in claim 1, it is characterized in that described solubilizing agent refer to contain the organic saturated or unsaturated fatty acids isoxazolecarboxylic acid of 12～32 carbon atoms or in the corresponding anhydride ester derivs any or plant arbitrarily and mix with arbitrary proportion.

7. as claim 1 or 6 described fat-soluble tea polyphenols, it is characterized in that described solubilizing agent optimal selection can for contain 16～22 carbon former organic saturated fatty isoxazolecarboxylic acid.