Abstract: The objective of this study was to determine the effect of heating treatment on physical and oxidative stability of oil bodies (OBs) from mature seeds of soybean, peanut and sunflower. The chemical compositions of seeds and OBs were analyzed, and the ζ-potentials, mean particle diameters, emulsifying properties, and lipid hydroperoxides of OBs at different temperatures were measured. The data we obtained demonstrated that there were significant differences in the chemical compositions of seeds, OBs and extracts among diverse oilseed crops (P < 0.05). The ζ-potential of soybean OBs was significantly higher than that of sunflower and peanut OBs (P < 0.05), while the mean particle diameter was significantly smaller (P < 0.05). There was no significant effect of thermal processing on the mean particle diameter of soybean or peanut OBs. The emulsifying activity indexes (EAI) of soybean and peanut OBs reduced from (61.32 ± 1.19) to (51.99 ± 0.90) m2/g, and from (57.50 ± 0.30) to (40.13 ± 1.51) m2/g, respectively, with increasing temperature from 30 to 80 ℃. However, the EAI of sunflower OBs at 50–70 ℃ was significantly higher than that at 30–40 ℃ and 80–90 ℃ (P < 0.05). These OBs were stable against oxidation at 4 and 25 ℃. When stored at elevated temperature, hydroperoxide formation in the oil from peanut OBs was significantly more than that in the oil from soybean and sunflower OBs (P < 0.05). These results suggested that OBs from diverse species had good emulsifying stability at certain temperatures, but were different from each other in physicochemical properties.

Key words: oil body, temperature, emulsifying property, oxidative stability