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CN-122004469-A - Microcapsule powder rich in SN-2DHA algae oil and preparation method thereof

CN122004469ACN 122004469 ACN122004469 ACN 122004469ACN-122004469-A

Abstract

The invention discloses microcapsule powder rich in SN-2DHA algae oil and a preparation method thereof, which belong to the technical field of marine food manufacturing, wherein SN-2DHA algae oil, lutein ester and an antioxidant are mixed and stirred under the protection of inert gas to form a uniform oil phase, cellulose nano fibers subjected to micro-jet homogenization treatment and whey protein composite wall materials are dispersed in deionized water, water phase dispersion liquid is formed through high-speed shearing and ultrasonic treatment, O/W type Pickering emulsion is formed through precise emulsification of a micro-fluidic chip, chitosan quaternary ammonium salt is added for electrostatic deposition reaction to realize interface solidification, pH response type gel outer layers are constructed through ionic crosslinking reaction of sodium alginate pectin and calcium ions, and the microcapsule powder is obtained through drying, crushing and screening.

Inventors

  • QIAN KAI
  • WANG LI
  • MENG ZHEN
  • LU JING

Assignees

  • 湖北欣和生物科技有限公司

Dates

Publication Date
20260512
Application Date
20260303

Claims (10)

  1. 1. The preparation method of the microcapsule powder rich in the SN-2DHA algae oil is characterized by comprising the following steps of: S1, mixing SN-2DHA algae oil, lutein ester and an antioxidant, and stirring under the protection of inert gas and in the dark to obtain an oil phase dispersion; s2, dispersing a composite wall material containing micro-jet homogeneous cellulose nanofiber and whey protein in deionized water, and performing high-speed shearing and ultrasonic treatment to form aqueous phase dispersion; S3, emulsifying the oil phase dispersion liquid obtained in the step S1 and the water phase dispersion liquid obtained in the step S2 through a microfluidic chip, and controlling the two-phase flow rate ratio to form O/W type Pickering emulsion with uniform oil drop particle size; S4, adding chitosan quaternary ammonium salt solution into the pickering emulsion obtained in the step S3 for electrostatic deposition reaction, realizing interface solidification, dripping sodium alginate pectin water solution into the pickering emulsion after interface solidification, uniformly stirring, adding calcium chloride solution for ionic crosslinking reaction to form a pH response type gel outer layer, and then drying to obtain the solid microcapsule; S5, crushing and screening the dried solid microcapsule to obtain microcapsule powder rich in SN-2DHA algae oil.
  2. 2. The method according to claim 1, wherein in the step S1, the antioxidant is mixed tocopherol, and the stirring temperature is 40-45 ℃ and the stirring time is 25-30 minutes.
  3. 3. The preparation method according to claim 1, wherein in the step S2, the mass ratio of the cellulose nanofiber to the whey protein in the composite wall material is 1:2 to 2:1, the cellulose nanofiber is subjected to a micro-jet homogenizer in advance, the treatment pressure is 100-120MPa, and the average diameter of the obtained cellulose nanofiber is 15-30nm, and the length of the obtained cellulose nanofiber is 150-350nm.
  4. 4. The preparation method of claim 1, wherein in the step S3, the microfluidic chip is a Y-shaped or T-shaped chip, the volume ratio of the oil phase dispersion liquid to the water phase dispersion liquid during emulsification is 1:3 to 1:3.5, the flow rate ratio is 1:8 to 1:9, the average particle size of the formed Pickering emulsion is 2.2-2.5 μm, and the variation coefficient CV value of the particle size is less than 12%.
  5. 5. The preparation method according to claim 1, wherein in the step S4, the concentration of the chitosan quaternary ammonium salt solution is 2-2.5%, and the mass ratio of sodium alginate to pectin in the sodium alginate fruit water solution is 2:1-4:1, and the concentration of calcium chloride is 0.5-1.0%.
  6. 6. The method according to claim 1, wherein in step S4, the drying is spray drying, the inlet air temperature is 165 ℃, and the outlet air temperature is 80 ℃.
  7. 7. The method according to claim 5, wherein the pectin is high methoxyl pectin, has a methoxylation degree of 60% -75% and a molecular weight of 30-100kDa.
  8. 8. A microcapsule powder enriched in SN-2DHA algae oil prepared by the preparation method of any one of claims 1-7, comprising, in parts by weight: 20-40 parts of SN-2DHA algae oil, 5-15 parts of lutein ester, 40-60 parts of composite wall material based on micro-jet homogeneous cellulose nanofiber and whey protein, 3-8 parts of chitosan quaternary ammonium salt, 0.5-2 parts of mixed tocopherol, 2-5 parts of sodium alginate, 1-2.5 parts of pectin and 0.3-0.8 part of calcium chloride; in the composite wall material based on the micro-jet homogeneous cellulose nanofiber and the whey protein, the mass ratio of the cellulose nanofiber to the whey protein is 1:2 to 2:1.
  9. 9. The microcapsule powder according to claim 8, wherein the microcapsule powder has a four-layer structure, the core is SN-2DHA algae oil and lutein ester, the inner layer is a composite wall material of cellulose nanofiber and whey protein, the middle layer is a chitosan quaternary ammonium salt polyelectrolyte composite layer, and the outer layer is a sodium alginate-calcium pectin pH response gel layer.
  10. 10. The microcapsule powder according to claim 8, wherein the chitosan quaternary ammonium salt is N- (2-hydroxypropyl) trimethyl ammonium chloride chitosan or N, N, N-trimethyl chitosan, the substitution degree is 60-90%, and the molecular weight is 50-200kDa.

Description

Microcapsule powder rich in SN-2DHA algae oil and preparation method thereof Technical Field The invention relates to the technical field of ocean food manufacturing, in particular to microcapsule powder rich in SN-2DHA algae oil and a preparation method thereof. Background Docosahexaenoic acid (DHA) is an important omega-3 long chain polyunsaturated fatty acid and plays an important role in the development of the nervous system of infants and the cardiovascular health of adults. Wherein, the SN-2 DHA (namely DHA esterified in the middle position of the glycerol skeleton) has higher bioavailability and is easier to be absorbed by intestinal tracts. However, DHA contains multiple unsaturated double bonds, and is extremely susceptible to oxidative deterioration, resulting in shortened shelf life and reduced nutritional value of the product. Lutein is a natural carotenoid, has the functions of filtering blue light, resisting oxidization and the like and protecting retina, and has synergistic effect with DHA in the field of eye health. However, lutein is also sensitive to light, heat and oxygen, is fat-soluble, has poor compatibility with a water-soluble system, and limits the application of lutein in food systems. Microencapsulation technology is an effective means of protecting sensitive functional factors and improving their stability and bioavailability. The traditional microcapsule technology is mainly prepared by adopting wall materials such as Arabic gum, maltodextrin and the like through spray drying, but the problems of low mechanical strength of the wall materials, low embedding rate of core materials, poor slow release performance and the like exist. In recent years, pickering emulsion (Pickering emulsion) is paid attention to because of the advantages of high stability, good biocompatibility and the like of using solid particles to replace traditional surfactants as an emulsifier, but how to select a proper solid particle stabilizer and optimize a preparation process to obtain a microcapsule product with high embedding rate and high stability is still a technical difficulty. Disclosure of Invention In order to solve the technical problems, the invention aims to negatively charge the interface of oil drops of the Pickering emulsion formed by regulating and controlling the pH of an aqueous phase and selecting cellulose nano fibers with negatively charged surfaces at a specific pH to be compounded with whey protein, thereby creating necessary conditions for the subsequent efficient electrostatic deposition reaction with positively charged chitosan quaternary ammonium salt, which is the key for constructing a high-strength interface curing layer. A preparation method of microcapsule powder rich in SN-2DHA algae oil comprises the following steps: S1, mixing SN-2DHA algae oil, lutein ester and an antioxidant, and stirring under the protection of inert gas and in the dark to obtain an oil phase dispersion; s2, dispersing a composite wall material containing micro-jet homogeneous cellulose nanofiber and whey protein in deionized water, and performing high-speed shearing and ultrasonic treatment to form aqueous phase dispersion; S3, emulsifying the oil phase dispersion liquid obtained in the step S1 and the water phase dispersion liquid obtained in the step S2 through a microfluidic chip, and controlling the two-phase flow rate ratio to form O/W type Pickering emulsion with uniform oil drop particle size; S4, adding chitosan quaternary ammonium salt solution into the pickering emulsion obtained in the step S3 for electrostatic deposition reaction, realizing interface solidification, dripping sodium alginate pectin water solution into the pickering emulsion after interface solidification, uniformly stirring, adding calcium chloride solution for ionic crosslinking reaction to form a pH response type gel outer layer, and then drying to obtain the solid microcapsule; S5, crushing and screening the dried solid microcapsule to obtain microcapsule powder rich in SN-2DHA algae oil. Further, the antioxidant is mixed tocopherol, the stirring temperature is 40-45 ℃, and the stirring time is 25-30 minutes. Further, in the step S2, the mass ratio of the cellulose nanofiber to the whey protein in the composite wall material is 1:2-2:1, the cellulose nanofiber is treated by a micro-jet homogenizer in advance, the treatment pressure is 100-120MPa, and the average diameter of the obtained cellulose nanofiber is 15-30nm, and the length of the obtained cellulose nanofiber is 150-350nm. Further, in the step S3, the microfluidic chip is a Y-shaped or T-shaped chip, the volume ratio of the oil phase dispersion liquid to the water phase dispersion liquid is 1:3-1:3.5 during emulsification, the flow rate ratio is 1:8-1:9, the average particle size of the formed pickering emulsion is 2.2-2.5 mu m, and the particle size variation coefficient CV value is less than 12%. Further, in the step S4, the concentration of the chitosan quatern