FIELD: inulin production.SUBSTANCE: invention can be used to obtain inulin from tubers of tuberous sunflower. The method for producing inulin includes threefold extraction with purified water heated to the boiling point from crushed vegetable raw materials, keeping the flask with the raw material and the extractant in an ultrasonic bath at a temperature of 80°C; separation of plant material 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. the stage of vacuum filtration of the precipitate in heated purified water, adding to it a 50% solution of calcium chloride and fine powder of aluminum oxide. Then it is kept and filtered under vacuum, the resulting filtrate is passed sequentially through ion-exchange columns with anion exchanger in hydroxyl form AB-17-8 and cation exchanger in hydrogen form KU-2-8, taking into account the capacity of ion-exchange resins to pH 6.5-7.5 of the eluate. Then, inulin is precipitated 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. Then the precipitate is filtered through a pre-dried ashless paper filter under vacuum; washing the filter cake, carried out sequentially with a solution of ethyl alcohol in purified water, taken in a volume ratio of 3:1, at a ratio of raw materials: solution of 1 g: 15 ml, and with a mixture of ethyl acetate and ethyl alcohol, taken in a volume ratio of 1: 1, at a ratio raw material: solution 1 g: 10 ml; drying the filter with the sediment at a temperature of 100 to 105°C to constant weight. Moreover, inulin is extracted from tuberous sunflower tubers, plant raw materials are crushed to a linear size of 0.5-1.0 mm. Threefold extraction with purified water heated to the boiling point is carried out at the ratio of raw materials: 1 portion of water 1 g: 15 ml, the flask with the raw materials and the extractant is kept in an ultrasonic bath at an ultrasound frequency of 30 kHz for 30 minutes, ethanol is used at all stages of inulin production at a concentration of 96%, the stage of filtering the precipitate is carried out under vacuum at a residual pressure of 0.3-0.7 atm. The precipitate obtained after the stage of filtration under vacuum is dissolved in purified water heated to 90°C. In this case, 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 30 minutes. Purification of inulin from impurities by dissolving, obtained after the stage of filtration under vacuum, the precipitate in heated purified water is carried out at a ratio of raw materials: water 1 g: 12 ml, passing the resulting filtrate successively through ion-exchange columns with anion and cation exchangers is carried out to the purity of inulin equal to 98.0%.EFFECT: invention is aimed at extracting purified inulin from tubers of tuberous sunflower with a degree of purity equal to 98.0 - 0.8%, with the yield of the target product up to 20.05% in terms of absolutely dry raw materials in the absence of the use of hazardous and toxic substances.1 cl, 3 dwg, 1 ex