Study on Oil Body Emulsion Stability of Soybean Seeds after Germination

Soybean was used as raw material, and the oil emulsion of soybean seeds after germination was taken as the research object. Measurement of emulsion stability, peroxide value, thiobarbituric acid value (TBARS value) and acid value, the stability of oil emulsion of soybean seeds at different germination times was compared, and the effects of different treatment conditions (NaCl concentration, pH and storage temperature) on the stability of oil emulsion of soybean seeds after germination were studied. The experimental results showed that the oil bodies extraction rate of soybean seeds decreased gradually after germination, There was no significant difference in the extraction rate between 20 h (12.36%±0.21%) and 27 h (10.89%±0.28%) (P>0.05), and the extraction rate decreased significantly after 27 h (P<0.05). The emulsion stability was also different at different germination time. The surface hydrophobicity of 27 h was the highest (99.78±0.88), and the emulsion stability was the best (23.49±0.39). After treatment with different NaCl concentrations, pH and storage temperatures, with the increase of NaCl concentration, the emulsifying activity of soybean oil emulsion after germination had no significant change (P>0.05). The emulsifying stability showed a downward trend when NaCl concentration was 0~150 mmol/L, and no significant change when NaCl concentration was higher than 150 mmol/L. The emulsifying stability was (4.75±0.12) min and (4.74±0.14) min when NaCl concentration was 150 and 200 mmol/L, respectively. However, the peroxide value increased significantly during 0~6 d of storage (P<0.05). The higher the pH was, the smaller the ζ-potential and emulsifying activity of the emulsion would be. When the pH was 4, the emulsifying activity was (19.13±0.23) m²/g, and the peroxide value and TBARS value changed significantly (P<0.05). The emulsion stability of soybean seed oil body at different germination time was different, and soybean oil body after 27 h germination was more stable than other germination time. NaCl concentration and pH had great effect on the stability of germinated soybean oil emulsion, and storage temperature had little effect on it. It could provide theoretical basis for the application of germinated soybean oil bodies in the future.