Background : The Food industry is trying to replace many synthetic with surfactants with natural alternatives, mainly inspired by consumer’s demand. Saponins are water-soluble small amphiphilie molecules that can be isolated from various natural sources. Especially, concentrated red ginseng extract (CRGE) contains saponins (called as ginsenoside) and they have been shown medical activities to help alleviate pathological symptoms, promote health and prevent potential diseases. In this study, we confirmed the effectiveness of this natural emulsifier for forming and properties of emulsions containing those. Methods and Results : CRGE was supplied D company, located in Geumsan. We examined the interfacial tension, emulsifying activity, fat globule size, dispersion stability, zeta-potential, microscopic observation. The interfacial tension decreased gradually with increasing CRGE concentration. In emulsion systems, as the concentration increases, fat globules sizes also becomes smaller as well as result of dispersion stability evaluated by separation analyzer (i.e., LUMiFuge) showed that it was more stable in emulsions with increasing CRGE concentration. CRGE-coated droplets were stable to droplet coalescence over a range of pH value (2 - 9), salt concentrations (0 - 500 mM NaCl). However, some flocculation was observed under highly acidic (pH 3) and high ionic strength (≧ 400 mM NaCl) conditions, which might be attributed to screening of electrostatic repulsion. Especially, CRGE-coated droplets had high negative charged at basic pH that decreased in magnitude with falling pH. Conclusion : Thus, CRGE have some emulsifying properties as well as medical activities. The results means that emulsions formed with CRGE may be able to replace synthetic surfactants in food industry.

• Kwan Mo You(Food emulsion laboratory, Dept. of Food Science and Technology, College of Agriculture and Life Science Chungnam National University) | 류관모 Corresponding author
• Hyeon Ho Jang(Food emulsion laboratory, Dept. of Food Science and Technology, College of Agriculture and Life Science Chungnam National University) | 장현호
• Eui Seok Lee(Food emulsion laboratory, Dept. of Food Science and Technology, College of Agriculture and Life Science Chungnam National University) | 이의석
• Ka Soon Lee(Ginseng and Medicinal Plant Research Institute, CNARES) | 이가순
• Soon Taek Hong(Food emulsion laboratory, Dept. of Food Science and Technology, College of Agriculture and Life Science Chungnam National University) | 홍순택