Investigation of the solubility enhancement mechanism of rebaudioside D using a solid dispersion technique with potassium sorbate as a carrier

• Published in: Food chemistry Vol. 174; pp. 564 - 570
• Main Authors: Pang, Shintaro, Ma, Changchu, Zhang, Naijie, He, Lili
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.05.2015
• Subjects: Diterpenes, Kaurane - analysis; Diterpenes, Kaurane - chemistry; FT-IR; Glycosides - analysis; Glycosides - chemistry; Microscopy, Electron, Scanning - methods; Raman; Rebaudioside D; SEM; Solid dispersion; Solubility; Sorbic Acid - chemistry; Spectroscopy, Fourier Transform Infrared - methods; Steviol glycosides; X-Ray Diffraction - methods; XRD; Rebaudioside D; Solubility; Solid dispersion; FT-IR; SEM; Raman; XRD; Steviol glycosides
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2014.11.113

•Solubility of rebaudioside D can be greatly enhanced by solid dispersion (SD).•Rebaudioside D-sorbate SDs were characterised by SEM, Raman, FT-IR and XRD.•Results indicate a co-complex formation through hydrogen bonding interaction.•Surface area/volume and SD concentration ratio were found to influence solubility. Rebaudioside (Reb) D is a high intensity, natural sweetener that shows great potential for substituting sugar in sweetened beverages. However, Reb D is poorly water soluble, and thus, a solid dispersion technique was recently established to enhance its solubility. The purpose of this study was to elucidate the solubility enhancement mechanism of this solid dispersion material by employing Scanning Electron Microscopy (SEM), Raman spectroscopy, Fourier Transform Infrared spectroscopy (FT-IR) and X-ray Diffraction (XRD). Potassium sorbate (KS) was chosen as the carrier and two different concentration ratios were investigated as solid dispersions (SD) and as physical mixtures (PM). Our data demonstrated the possible mechanism for enhancing solubility through solid dispersion through increased surface area/volume ratio and hydrogen bonding between Reb D and KS. The interaction between the two components were also related to the different concentration ratios, therefore an optimisation of the ratio is important to produce a soluble and stable complex.