Abstract:Corn enzymatic hydrolysate was prepared via enzymatic hydrolysis of corn gluten meal using commercial enzymes. The sites for cleavage by a protease are coated, causing low efficiency of enzymatic hydrolysis, and brownish yellow colour in the corn enzymatic hydrolysate, (which is not conducive to the separation and purification of peptides and affects product sensory effect). This research compared the pretreatment methods of corn gluten meal, and it was determined that the corn gluten meal was pretreated by heating and α-amylase to improve the efficiency of subsequent enzymatic hydrolysis. The corn enzymatic hydrolysate was decolorized by activated carbon, and the optimum decolorization conditions were determined based on the decolorization rate and protein loss rate: decolorization pH was 5, decolorization temperature was 40 ℃, and activated carbon dosage was 2%. Through the investigation on the antioxidant activities of decolorized corn peptides, it was found that the DPPH, ABTS and ORAC radical scavenging rates decreased: they were 93.11%, 1318.97 μmol TE/g, and 1192.39 μmol TE/g, respectively, before decolorization, but were 33.19%, 858.36 μmol TE/g and 582.62 μmol TE/g, respectively, after decolorization (i.e. the decolorized corn peptides still retained significant antioxidant activity). The determination of the ADH activation rate and hydrolyzed amino acids of the decolorized corn peptide showed that the ADH activation rate was 48.74%, and the decolorized corn peptide contained high levels of leucine and alanine, indicating its sobering activity.
