Abstract: In order to explore the effect of cavitation microjet as a new physical modification technology on the structure of soybean dreg protein from aqueous enzymatic extraction of soybean oil, we determined the Raman spectra of soybean dreg protein subjected to different durations of cavitation microfluid treatment (0, 5, 10 and 15 min). The results showed that after cavitation microjet treatment, the proportions of the secondary structure fractions α-helix and β-sheet increased significantly (P < 0.05), and the proportions of β-turn and random coil decreased. The tryptophan and tyrosine residues were in an exposed state; the proportions of disulfide bond modes g-g-g and g-g-t increased while t-g-t decreased. To sum up, cavitation microjet could result in a structural transformation of soybean dreg protein from a disordered to an ordered state, thus improving its stability. This study provides a basis for the development and utilization of soybean dregs from aqueous enzymatic extraction of soybean oil.

Key words: soybean dreg protein from aqueous enzymatic extraction of soybean oil, cavitation microjet, soybean dreg protein, Raman spectroscopy