Clarification of Stevia rebaudiana Bertoni extract by Ca based silica microspheres

Abstract

Pre-treated Stevia rebaudiana Bertoni extract was clarified via using calcium (Ca) based silica (Si) microspheres. Both adsorption and chemical treatment were applied to extracts, and their effects on clarification were determined by comparison. The study aimed to maintain the highest level of clarity by eliminating chemicals from the treatment procedure. Although close in range with chemical treatment, the highest level of clarity was obtained in the presence of sole Ca/Si application. Clarification was achieved in an interval of 95–99 % with applied procedures. Sustainable utilization of Ca/Si microspheres was investigated by conducting three consecutive adsorption cycles with used microspheres. Results indicated minor changes in clarification levels at the end of three straight runs with used microspheres. Sustainable adsorption of impurities from the extract without the use of additional chemicals was the highlight of the present study.