ABSTRACT
Objective To determine hydrophilic–lipophilic balance (HLB) value, stability of formulate emulsion and properties of sacha inchi oil. Methods The physiochemical characteristics of sacha inchi oil were first investigated. Free radical scavenging property was studied by DPPH assay. HLB value of sacha inchi oil was experimentally determined by preparing the emulsion using emulsifiers at different HLB value. Sacha inchi oil emulsion was prepared using the obtained HLB and its stability was conducted by centrifugation, temperature cycling, and accelerated stability test. The efficiency of the prepared emulsion was clinically investigated by 15 volunteers. The primary skin irritation was performed using closed patch test. Subjective sensory assessment was evaluated by using 5-point hedonic scale method. Results Peroxide value of sacha inchi oil was 18.40 meq O