METHOD FOR OBTAINING INULIN FROM VEGETABLE RAW MATERIALS Russian patent published in 2022 - IPC C08B37/18 

FIELD: inulin production.

SUBSTANCE: invention can be used to obtain inulin from burdock roots. The method of obtaining inulin from plant raw materials includes threefold extraction with purified water heated to the boiling point at the ratio of raw materials: 1 portion of water 1 g: 20 ml, from crushed plant materials to a linear size of 0.2-0.5 mm, keeping the flask with the raw material and extractant in an ultrasonic bath with a frequency of 25 kHz at a temperature of 80°C for 40 minutes. In this case, the ratio of raw materials: extractant is 1 g:20 ml. Separation of plant material is carried out by filtration; precipitation of water-soluble polysaccharides with a threefold amount of ethanol in relation to the water extraction with stirring, cooling in a freezer at a temperature of -18°C for 1 hour; filtering the precipitate through a pre-dried ashless paper filter under vacuum. Inulin is purified from impurities by dissolving the precipitate obtained after the vacuum filtration stage in heated purified water, add to it a 50% solution of calcium chloride and fine powder of aluminum oxide, then stand and filter under vacuum, pass the resulting filtrate sequentially through ion-exchange columns with anionite in hydroxyl form AV-17-8 and cation exchanger in the hydrogen form KU-2-8, taking into account the capacity of ion-exchange resins to pH 6.5-7.5 eluate. After that, precipitation of inulin is carried out by adding again to the eluate a threefold amount of ethanol in relation to the aqueous solution with stirring, cooling in a freezer at a temperature of -18 ° C for 1 hour, filtering the precipitate through a pre-dried ashless paper filter under vacuum at a residual pressure of 0, 3-0.7 atm, washing the precipitate on the filter, carried out sequentially with a solution of ethyl alcohol in purified water, taken in a volume ratio of 3: 1, with a raw material: solution of 1 g: 15 ml, and a mixture of ethyl acetate and ethyl alcohol, taken in volume ratio 1: 1, with a ratio of raw materials: solution 1 g: 10 ml. The filter with the sediment is dried at a temperature of 100 to 105°C to constant weight. Moreover, inulin is extracted from the roots of large burdock. At all stages of obtaining inulin, ethanol is used in a concentration of 96%, while the precipitate obtained after the stage of filtration under vacuum is dissolved in purified water heated to 90°C, a 50% solution of calcium chloride is added at the rate of 10 drops per 1 g of the initially taken plant material, and the mass of finely dispersed aluminum oxide powder is 0.7 g, the holding time is 40 minutes. Purification of inulin from impurities is carried out by dissolving the precipitate obtained after the stage of filtration under vacuum in heated purified water at a ratio of raw materials: water of 1 g: 12 ml. The resulting filtrate is passed sequentially through ion-exchange columns with anion and cation exchangers until the purity of inulin is 98.5%.

EFFECT: invention is directed to the extraction of purified inulin from the roots of burdock with a purity level of 98.5 - 0.5%, with the yield of the target product up to 23.07% in terms of absolutely dry raw materials in the absence of the use of hazardous and toxic substances.

1 cl, 3 dwg, 1 ex