Adsorptive precipitation of vitamin D3 and vitamin E on gum arabic and sodium alginate using supercritical carbon dioxide

• Author / Creator

  Vilchez Athanasopulos, Andrea Carolina

• Functional food products are formulated with added ingredients that provide health benefits beyond basic nutrition function. However, there are different challenges in the manufacturing of these products with fat-soluble vitamins, such as, vitamin D3 (VitD3), an essential nutrient responsible for increasing intestinal absorption of calcium and phosphorus, and vitamin E (VitE), a powerful antioxidant that plays an important role in the prevention of many disorders. Some challenges are their high tendency to be degraded or oxidized by heat, light and presence of oxygen, and also their hydrophobic nature limits their further use in aqueous-based products. To overcome these limitations, water-soluble biopolymers can be used as delivery systems. The polysaccharides, gum arabic (GA), and sodium alginate (SA), were dried using the Pressurized Gas eXpanded (PGX) liquid technology, a drying method for high molecular weight water-soluble biopolymers to produce unique morphologies of micro- or nano-sized particles. Then, adsorptive precipitation, an environmentally friendly technology to load hydrophobic bioactives homogeneously onto the biopolymers without the use of any organic solvents, was used to develop novel delivery systems. The objectives of this MSc thesis research were to investigate the effect of adsorptive precipitation process parameters on the loading of fat-soluble bioactive compounds (VitD3 and VitE) on water-soluble biopolymers (GA and SA), and to characterize the powders obtained to ultimately increase the application of these hydrophobic compounds in aqueous-based products. The VitD3 and VitE loaded PGX-GA and PGX-SA particles obtained by adsorptive precipitation under different recirculation flow rates and times were investigated in terms of the vitamin loading content, particle morphology, molecular interactions, thermal behavior, storage stability, and release kinetics. In addition, adsorption kinetics were evaluated for VitE.
  The higher loading of VitD3 on the biopolymers was achieved at the recirculation flow rate of 190 mL/min as 10.1 ± 0.2% for GA and 250 mL/min as 13.7 ± 0.1% for SA at 45 min of recirculation time. Uniform coating of VitD3 on the surface of biopolymers was demonstrated by helium ion microscopy (HiM). VitD3 retained some crystalline form on the loaded gum arabic (L-GA). Over 60 days of refrigerated storage, after an initial decrease, the loading of samples stabilized after 21 days for L-SA at 82% and after 28 days L-GA at 80% of the original VitD3 levels. Sustained release of VitD3 was demonstrated for L-GA sample in the simulated intestinal fluid.
  For VitE, the highest loading was achieved at the same processing conditions (135 mL/min and 45 min) for both biopolymers with maximum values of 14.95 ± 0.2% for GA, and 22.35 ± 0.1% for SA. Homogeneous coating of VitE on the biopolymers’ surface was displayed by HIM images. Loaded samples were quite stable over storage for 28 days with a drop of VitE loading to 91% for GA and 96% for SA of the initial loading. Adsorption kinetics results showed a difference in the rate of the concentration increase up to 50 min for both biopolymers, indicating differences in the surface areas of the biopolymers as well as the interactions between VitE and biopolymers.
  The findings on adsorptive precipitation of VitD3 and VitE on the PGX-processed gum arabic and sodium alginate powders demonstrated the great potential of this technology and these food biopolymers for use as delivery systems of fat-soluble vitamins, targeting subsequent aqueous-based product applications.

• Subjects / Keywords

  • Adsorptive precipitation

• Graduation date

  Fall 2020

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-w8tt-q150

• License

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