Preparation method for tea polyphenol oil-soluble derivative used as anti-oxidant for edible oil

Abstract

The invention provides a preparation method for a tea polyphenol oil-soluble derivative used as an anti-oxidant for edible oil. The preparation method is characterized by comprising the following steps: (1) acylation reaction: a step of adding, by weight, 100 parts of tea polyphenol, 50 to 500 parts of acyl chloride and 0.05 to 10 parts of a catalyst into a reactor equipped with a stirrer, a thermometer and a gas guiding-in and guiding-out opening, introducing nitrogen, carrying out heating to 50 to 180 DEG C under stirring, then carrying out the reaction until a system is uniform and transparent and then carrying out cooling to room temperature; (2) rearrangement reaction: a step of adding 10 to 400 parts by weight of a rearrangement aid into reactant, carrying out heating and stirring until the obtained mixture is solidified, placing the solidified mixture into a baking oven, maintaining the mixture at 100 to 180 DEG C for 0.5 to 5 h, then cooling the mixture to room temperature, adding 100 to 1000 parts by weight of an acid / aqueous solution with a pH value of less than 2 and 100 to 1000 parts by weight of an extracting agent, carrying out uniform stirring, removing a water phase and repeatedly washing an extracting agent phase five time by using the acid / aqueous solution with a pH value of less than 2; and (3) reduction reaction: a step of adding 50 to 500 parts by weight of a reducing agent / aqueous solution with a concentration of 20% into a product obtained in the step (2), carrying out stirring for 5 to 72 h, washing the extracting agent phase with water until the extracting agent phase is neutral and removing the extracting agent so as to obtain the tea polyphenol oil-soluble derivative.

Description

technical field [0001] The invention relates to a method for preparing an alkylated derivative of polyhydroxybenzene used as an antioxidant, in particular to a method for preparing an oil-soluble derivative of tea polyphenol used as an antioxidant for edible oil. Background technique [0002] Tea polyphenols, also known as tea tannins, belong to plant polyphenols. According to GB8313-87, tea polyphenols refer to the general term for phenolic compounds that react comprehensively with ferrous ions in tea water extracts. Tea polyphenols Licorice substances are not only the main substances that determine the flavor and quality of tea, but also an excellent natural antioxidant, and also the substances that play a leading role in the pharmacological effects of tea. In recent years, the development and utilization of tea polyphenols and their derivatives have attracted great attention from tea science, medicine and food industry at home and abroad. The chain or o-phenol group in t...

AI Technical Summary

Problems solved by technology

Although it has an anti-oxidant effect, after the ethanol evaporates, some tea polyphenols precipitate out of the oil in a crystalline state, which not only affects the appearance of the oil, but also the residual ethanol will also affect the taste of the oil. At present, there are also methods to prepare oil-soluble tea polyphenols. Patent reports, but most of them use organic solvents that are not easy to remove, and after esterification (or acylation), there are few active phenolic hydroxyl groups, and the antioxidant activity of the product is greatly lost, which will inevitably reduce the antioxidant performance of the product.