Response surface optimization of spray-dried citronella oil microcapsules with reduced volatility and irritation for cosmetic textile uses

A two-step approach, which included oil-in-water emulsification and spray drying, was employed to encapsulate citronella oil in acacia gum microcapsules. Crucial parameters that affect the quality of spray-dried citronella oil microcapsules were simultaneously evaluated. A central composite design was utilized to determine the optimum processing conditions as a function of various parameters. The optimal microencapsulation conditions consisted of an acacia gum percentage, citronella oil percentage and inlet air temperature of 14% w/w, 26% w/w of the wall material and 150 degrees C, respectively. Moreover, prolonged volatility and reduced irritation properties of citronella oil in the microcapsules were demonstrated. Scanning electron microscopy revealed that the microcapsules can be easily impregnated onto a nonwoven fabric. The resulting microcapsules not only have the potential to offer prolonged volatility of the odor with reduced irritation but also are a candidate for the further development of citronella essential oil-based cosmetic textiles. (C) 2019 Elsevier B.V. All rights reserved.