Abstract:

A UV spectrophotometric method was established to determine the undesirable flavor in soybean peptide. Totally 60 mL of soybean peptide solution in 100 mL saline bottle was adjusted to pH 6.0 with NaCl concentration 4 g/60 mL, sealed with a rubber plug and heated at 50 ℃ for 1 hour. In the following, totally 20 mL headspace gas in the bottle was collected with a syringe and absorbed in 5 mL of 0.2 mol/L NaOH, then the absorbance of the NaOH solution at 217 nm was used to express the relative content of undesirable flavor in soybean peptide. This method is simple and quick, which can be applied to detect undesirable flavor in soybean peptide.

Key words: undesirable flavor, ultraviolet spectrophotometry, soybean peptide, detection