Effects of ultrafiltration and hydrolysis on antioxidant activities of Maillard reaction products derived from whey protein isolate and galactose

摘要

Impacts of ultrafiltration and hydrolysis on antioxidant abilities of Maillard reaction products (MRPs) derived from whey protein isolate (WPI) and galactose (Gal), were evaluated in this study. Fraction (MW > 50 kDa) of WPI-Gal MRPs prepared with ultrafiltration, had the strongest antioxidant activity. The trichloroacetic acid (TCA, 2-8%) treatment could effectively enhanced antioxidant activities of WPI-Gal MRPs. WPI-Gal MRPs had higher degrees of hydrolysis and antioxidant activity than heated WPI. With hydrolysis time of pepsin and trypsin extended up, degrees of hydrolysis and antioxidant activities of WPI-Gal MRPs and WPI gradually increased (P < 0.05). Furthermore, reverse phase HPLC analysis showed that WPI-Gal MRPs was easier to be hydrolyzed and had smaller molecular peptides than heated WPI.