Abstract:

In this research the influence of ultrasonic treatment on low-purine defatted soybean powder was analyzed using
visible spectrophotometer, laser particle size distribution analyzer and fluorescence spectrophotometer. Results suggested
that free sulfhydryl content, average particle size, size distribution width and protein surface hydrophobicity of the sample
after ultrasonic treatment were significantly higher than those of control samples without ultrasonic treatment (P < 0.05).
Treatment with an ultrasonic power of 405 W at 50 ℃ for 30 min yielded maximum sulfhydryl content of 8.75 mmol/g.
Protein surface hydrophobicity of 3.86% was obtained when the ultrasonic treatment was performed by irradiation with
450 W ultrasonic waves at 40 ℃ for 60 min. Therefore, ultrasonic treatment can change sulfhydryl content, particle size
distribution, and protein surface hydrophobicity of low-purine defatted soybean powder.

Key words: ultrasonic treatment, low-purine defatted soybean powder, sulfhydryl content, particle size distribution, surface hydrophobicity