Applicability of transglycosylated stevia for oil-in-water submicron emulsions by high-pressure homogenization

An oil-in-water emulsion with submicron particle size was prepared using a high-pressure homogenizer (HPH) in the presence of transglycosylated stevia (Stevia-G). Before HPH processing, the emulsions were coarse and microscale in particle size. Although Stevia-G has weak surface-active properties, HPH enabled the preparation of submicron emulsions. HPH processing conditions affected the particle size and encapsulation efficiency of flavanone. The particle size of emulsions did not change upon storage and the encapsulation efficiency of flavanone was 85.1 +/- 2.9% at an operating pressure of 100 MPa. The HPH-processed emulsions were successfully powdered by freeze-drying with trehalose and exhibited similar particle sizes and encapsulation efficiencies to those prior to freeze-drying. After digestion of the emulsions in simulated gastrointestinal fluid, the HPH-processed emulsions showed higher flavanone concentrations compared to flavanone powder. HPH reduces the oil droplet size and Stevia-G acts as an emulsifier to stabilize submicron emulsions.