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CN-122011063-A - Preparation method of high-purity rubusoside

CN122011063ACN 122011063 ACN122011063 ACN 122011063ACN-122011063-A

Abstract

The application relates to the technical field of food processing, and particularly discloses a preparation method of high-purity rubusoside, which comprises the following steps of (1) taking rubus suavissimus raw materials, crushing, extracting with water to obtain rubus suavissimus powder extract, (2) filtering the rubus suavissimus powder extract, purifying by macroporous resin, decoloring by ion exchange resin, concentrating, drying, crushing to obtain a rubusoside crude product, (3) taking rubusoside crude product, dissolving in 65-75% ethanol aqueous solution, cooling to 8 ℃ by 60 ℃, carrying out gradient crystallization, carrying out heat preservation for 1-2h, filtering and drying to obtain a primary crystallization product, and (4) taking the primary crystallization product, dissolving in 90-95% ethanol aqueous solution, carrying out heat preservation for 1.5-2.5h by 60 ℃, cooling to 25 ℃, carrying out heat preservation for 3.5-4.5h, cooling to 8 ℃ and carrying out heat preservation for 11-13h, and filtering and drying to obtain the rubusoside. The application combines the control of solvent concentration, the design of temperature gradient and the optimization of heat preservation time through two-step gradient crystallization, thereby remarkably improving the purity, crystallization quality and storage stability of the product.

Inventors

  • LIAO NA
  • ZHANG BAOTANG
  • TAN JIAZHONG
  • LONG WEIAN
  • LIU XIAOYANG

Assignees

  • 湖南绿蔓生物科技股份有限公司

Dates

Publication Date
20260512
Application Date
20260310

Claims (9)

  1. 1. The preparation method of the high-purity rubusoside is characterized by comprising the following steps of: (1) Crushing raw materials of sweet tea leaves, and extracting with water to obtain sweet tea powder extract; (2) Filtering the sweet tea powder extract obtained in the step (1), purifying by macroporous resin, decolorizing by ion exchange resin, concentrating, drying and pulverizing to obtain crude sweet tea glycoside; (3) Dissolving the crude rubusoside obtained in the step (2) in 65-75% ethanol water solution, cooling to 8 ℃ from 60 ℃ for gradient crystallization, preserving heat for 1-2h, filtering, and drying to obtain a primary crystallization product; (4) Dissolving the primary crystallization product obtained in the step (3) in 90-95% ethanol water solution, preserving heat for 1.5-2.5h at 60 ℃, then preserving heat for 3.5-4.5h after cooling to 25 ℃, finally preserving heat for 11-13h after cooling to 8 ℃, and obtaining high-purity rubusoside through filtering and drying.
  2. 2. The method for preparing high-purity rubusoside according to claim 1, wherein in the step (3), the cooling rate of 60 ℃ to 8 ℃ is 0.4-0.6 ℃ per minute.
  3. 3. The method for preparing high-purity rubusoside according to claim 1, wherein in the step (4), the cooling rate of cooling 60 ℃ to 25 ℃ is 0.3-0.5 ℃ per minute, and the cooling rate of cooling 25 ℃ to 8 ℃ is 0.1-0.2 ℃ per minute.
  4. 4. The method for preparing high-purity rubusoside according to claim 1, wherein the ethanol aqueous solution in the step (3) and the ethanol aqueous solution in the step (4) are added with 0.1-0.3% of functional auxiliary agent, the functional auxiliary agent consists of citric acid, malic acid, polyaspartic acid and tween 80, and the weight ratio of the citric acid, the malic acid, the polyaspartic acid and the tween 80 is (2-3): (0.5-1).
  5. 5. The method for preparing high-purity rubusoside according to claim 4, wherein the weight ratio of citric acid, malic acid, polyaspartic acid and Tween 80 is 2:1:1:1.
  6. 6. The method for preparing high-purity rubusoside according to claim 1, wherein in the step (3), seed crystals with the mass ratio of 0.1-0.5% of the obtained solution are added after the rubusoside crude product is dissolved in 65-75% of ethanol aqueous solution.
  7. 7. The method for preparing high-purity rubusoside according to claim 1, wherein in the step (1), the extraction temperature is 70-90 ℃, ultrasonic auxiliary treatment is carried out in the extraction process, and the frequency of ultrasonic waves is 40-50kHz.
  8. 8. The method for preparing high-purity rubusoside according to claim 1, wherein in the step (2), the process flow of the filtering operation comprises ceramic microfiltration membrane prefiltering, 5KD hollow fiber ultrafiltration membrane filtering and nanofiltration membrane fine purification filtering in sequence.
  9. 9. The method for preparing high-purity rubusoside according to claim 1, wherein in the step (2), activated carbon is used for treatment during the concentration treatment.

Description

Preparation method of high-purity rubusoside Technical Field The application relates to the technical field of food processing, in particular to a preparation method of high-purity rubusoside. Background The rubusoside is also called rubusoside, is extracted from sweet tea of Rosaceae, has content of 2% -5% in dry leaf of sweet tea, and is a natural high-sweetness sweetener. The rubusoside has fresh and cool sweetness at low concentration, weak after-bitter taste and after-astringent taste, and strong after-bitter taste at high concentration, but can feel comfortable after oral cavity adaptation, has unique flavor, and meanwhile, the rubusoside has outstanding performance under high-temperature environment, good thermal stability and wide application in tea drinks. The rubusoside is produced through crushing material, wind separation to eliminate leaf stalk and other impurity, water extraction, centrifugal filtering, resin chromatographic purification, decolorizing, drying to obtain rubusoside product, and repeated crystallization. The invention patent application with the publication number of CN105166198A discloses a preparation method of high-purity rubusoside, which comprises the following steps of (1) crushing rubus suavissimus to 20-40 meshes, extracting with water to obtain rubus suavissimus powder extract, (2) allowing the rubus suavissimus powder extract to pass through a hollow fiber ultrafiltration membrane system with the molecular weight cut-off of 1-10kDa, allowing the permeate to enter a reverse osmosis membrane system, concentrating the extract until the solid content reaches 10-30%, drying and crushing the concentrated solution to obtain a rubusoside crude product, (4) dissolving the rubusoside crude product with 6-10 times of ethanol at 60 ℃, filtering, standing for 24 hours, obtaining a primary crystallization product, and (5) dissolving the primary crystallization product with 6-8 times of ethanol at 60 ℃, filtering, standing for more than 24 hours, filtering and drying to obtain the high-purity rubusoside. The preparation method has no pollution in the treatment process, integrates the separation and concentration steps through a membrane system, reduces the treatment difficulty, and can obtain the rubusoside with the purity of more than 98%. For the above related art, the inventors believe that during the crystallization treatment, both crystallization is performed by using the same solvent ethanol and temperature, which results in limited purification efficiency and poor crystal morphology, while during the storage of rubusoside, if the rubusoside is affected by frequent temperature changes, oxidation occurs, and serious oxidation phenomenon can cause the sweet taste of rubusoside to be greatly reduced, possibly causing rancidity or bitter and astringent taste, and can be easily combined with polyphenols and proteins in tea soup to form flocculent precipitate or cloudiness, which affects the appearance and texture ‌ of the product. Therefore, there is a need to propose a solution to the above technical problems. Disclosure of Invention In order to further improve the purity of the rubusoside product and improve the crystallization effect in the process of preparing the rubusoside product, and bring about remarkable improvement of storage stability, the application provides a preparation method of high-purity rubusoside. The application provides a preparation method of high-purity rubusoside, which adopts the following technical scheme: a preparation method of high-purity rubusoside comprises the following steps: (1) Crushing raw materials of sweet tea leaves, and extracting with water to obtain sweet tea powder extract; (2) Filtering the sweet tea powder extract obtained in the step (1), purifying by macroporous resin, decolorizing by ion exchange resin, concentrating, drying and pulverizing to obtain crude sweet tea glycoside; (3) Dissolving the crude rubusoside obtained in the step (2) in 65-75% ethanol water solution, cooling to 8 ℃ from 60 ℃ for gradient crystallization, preserving heat for 1-2h, filtering, and drying to obtain a primary crystallization product; (4) Dissolving the primary crystallization product obtained in the step (3) in 90-95% ethanol water solution, preserving heat for 1.5-2.5h at 60 ℃, then preserving heat for 3.5-4.5h after cooling to 25 ℃, finally preserving heat for 11-13h after cooling to 8 ℃, and obtaining high-purity rubusoside through filtering and drying. According to the technical scheme, in the operation process of the step (3), the 65-75% ethanol aqueous solution is selected, the solubility and impurity selectivity of rubusoside are balanced, the solubility of polysaccharide impurities is obviously reduced, the intermolecular acting force of rubusoside can be enhanced, the crystal nucleus purity is improved, the crystal selectivity is better in performance, gradient crystallization is carried out by cooling from 60 ℃ to 8 ℃, the crystal nucleus is