OBJECTIVE To prepare hemp seed oral emulsion, optimize the formulation and preparation process, and evaluate its quality.

MEDTHODS Single factor investigation and response surface optimization were used to optimize the formulation and preparation process of hemp seed oral emulsion with particle size, particle size distribution(PDI) and Zeta potential as indexes. The appearance, stratification, stability constant, pH value, particle size and Zeta potential of oral emulsion of hemp seed were used to evaluate its quality.

RESULTS The best prescription was 11% of sesame seed, 0.79% of emulsifier(phospholipid∶soluble soybean polysaccharide=6∶4), 0.1% of carrageenan and 0.1% of NaHCO₃. The optimal process was a high speed dispersing homogenizer 15 000 r·min⁻¹ shear for 5 min with homogenizing pressure, times and temperature of 90 MPa, 10 times and 60 ℃, respectively. There was no delamination after centrifugation at 4000 r·min⁻¹ for 15 min. The emulsion pH value was 7.81, the particle size was(219.0±1.74) nm, the PDI was(19.2±1.53)%, and the absolute value of Zeta potential was (27.8±0.4)mV.

CONCLUSION The prepared oral emulsion of hemp seed has uniform appearance, no stratification phenomenon, and good stability. It conforms to the provisions of pharmacopoeia for oral emulsion, and provides a reference for comprehensive development and utilization of hemp seed.