Abstract:

In this study, an optimized method was presented for the decolorization of soybean peptide by stepwise treatment
with activated carbon and AB-8 resin. An orthogonal array design was used to optimize activated carbon amount, time,
temperature and pH based on decolorization rate and peptide loss rate. The optimal conditions for activated carbon treatment
were determined to be decolorization at 55 ℃ for 50 min with the addition of 2.0% of activated carbon adjusted to pH
8.0, giving rise to a decolorization rate of 57.13% and a peptide loss of 11.37%. Further decolorization was performed by
9 h treatment with AB-8 resin (0.5 g/mL), resulting in a decolorization rate of 57.99% and a peptide loss of 16.19%. The
total decolorization rate and total peptide loss were 81.97% and 26.74%, respectively, after the two-stage decolorization.

Key words: soybean peptide, activated carbon, AB-8 resin, decolorization