Preparation and characterization of water-in-oil-in-water emulsions containing a high concentration of L-ascorbic acid

Biosci Biotechnol Biochem. 2013;77(6):1171-8. doi: 10.1271/bbb.120870. Epub 2013 Jun 7.

Abstract

This study sought to encapsulate a high concentration of L-ascorbic acid, up to 30% (w/v), in the inner aqueous phase of water-in-oil-water (W/O/W) emulsions with soybean oil as the oil phase. Two-step homogenization was conducted to prepare W/O/W emulsions stabilized by a hydrophobic emulsifier and 30% (v/v) of W/O droplets stabilized by a hydrophilic emulsifier. First-step homogenization prepared W/O emulsions with an average aqueous droplet diameter of 2.0 to 3.0 μm. Second-step homogenization prepared W/O/W emulsions with an average W/O droplet diameter of 14 to 18 μm and coefficients of variation (CVs) of 18% to 25%. The results indicated that stable W/O/W emulsions containing a high concentration of L-ascorbic acid were obtained by adding gelatin and magnesium sulfate in the inner aqueous phase and glucose in both aqueous phases. L-Ascorbic acid retention in the W/O/W emulsions was 40% on day 30 and followed first-order kinetics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascorbic Acid / chemistry*
  • Ascorbic Acid / metabolism
  • Drug Stability
  • Emulsions / chemistry*
  • Gelatin / chemistry
  • Humans
  • Kinetics
  • Magnesium Sulfate / chemistry
  • Particle Size
  • Soybean Oil / chemistry
  • Water / chemistry*

Substances

  • Emulsions
  • Water
  • Magnesium Sulfate
  • Soybean Oil
  • Gelatin
  • Ascorbic Acid