Effect of salt concentration and temperature on the rheological properties of guar gum-dead sea salt gel

Abstract

Dead Sea Salt (DSS) contains 21 minerials including magnesium, calcium, sulfur, bromide, iodine, sodium, zinc and potassium etc. On the other hand, Guar Gum (GG) is a natural polysaccharide, water soluble, having highest molecular weight and good gelling property. Due to such advantageous properties of DSS and GG, it has been taken interest to prepare a user friendly medicated gel (designated as GG-DSS gel) adding additional ingredients:e.g. Glycerol, Thymol, Ethanol, Seabuckthorn oil, and essencial oils for the improvment of the gel's medicated values and healing properties for the curing of general skin diseases/treatment. In this study, the viscoelastic behavior of GG-DSS gels were characterized by dynamic storage (G') and loss (G") moduli and complex viscosity as a function of angular frequency. The effect of DSS concentration and temperature on these properties of GG-DSS gels was investigated. All GG-DSS gels having different amount DSS shows G' higher than G" over a wide range of angular frequency. Both moduli have the trends to increase with the increase of temperature (temperature varies from 28°C to 50°C), and increase with the increase of DSS concentration higher than about 10%. In conclusion, it can be mentioned that the knowledge about the rheological properties of DSS-GG gels may be useful during the characterization of similar kinds of medicated gel. © 2016 Author(s).