Abstract: The objective of this study was to determine the differences in the structure and properties of oil bodies from diverse oilseed crops (soybean, peanut, and sunflower). The structure, composition, protein molecular mass, zeta potential, particle size distribution, emulsifying properties, and circular dichroism (CD) spectra of proteins of oil bodies were analyzed and compared under the same conditions. The experimental results showed that the oil bodies from different oilseed crops had similar composition and structure. The ratio of protein to fat in soybean oil bodies (0.086:1) was significantly higher than that in peanut oil bodies (0.018:1) and sunflower oil bodies (0.028:1) (P < 0.05). The average particle size of soybean oil bodies, (0.93 ± 0.07) μm, was significantly smaller than that of peanut oil bodies, (2.58 ± 0.06) μm, and sunflower oil bodies, (1.64 ± 0.03) μm (P < 0.05). The total amount of hydrophobic amino acids in soybean oil bodies was the highest, while the lowest value was observed in peanut oil bodies. The zeta potential, emulsifying activity and emulsion stability of soybean oil bodies were significantly higher than those of peanut oil bodies and sunflower oil bodies (P < 0.05). The α-helix content of proteins in soybean oil bodies ((43.58 ± 0.12)%) was significantly higher than that in peanut oil bodies ((35.43 ± 0.06)%) and that in sunflower oil bodies ((37.00 ± 0.09)%) (P < 0.05); however the β-sheet and random coil content of proteins in peanut oil bodies were the highest. The results show that there are differences in the properties of oil bodies from diverse oilseed crops (soybean, peanut, and sunflower) although they have similar composition and structure, which can provide a theoretical basis for future application of oil bodies in the food industry.

Key words: oilseed crop, oil bodies, oil body protein, stability