Investigation of effective factors in shelf life of limonene microcapsules encapsulated with whey protein concentrate (WPC)

In this study, the effect of wall material concentration, homogenization time of fresh emulsion and re-dispersed Emulsion on the shelf life of microcapsules were investigated. Colloidal suspensions with concentrations of 10, 15 and 20 % (w/w) whey protein concentrate and limonene in water (oil/water emulsion) were prepared. The above suspensions were transformed to the emulsion after homogenization for 3, 6 and 9 minutes. The emulsified solutions were encapsulated with spray drying process and consequently the properties of powder particle size were determined. In order to detect the stability of wall material and the release rate of limonene, microcapsules were stored at room temperature for 6 weeks. The results indicated that an increase in wall material concentration and homogenization time of fresh emulsion decreased the release rate of limonene. Also the study of re-dispersed emulsion showed that an increase in emulsion size results leads to a decrease in release rate of limonene.