Structure and Antioxidant Activity of Milk Model Systems after Microwave Heating

The milk proteins were mixed with lactose in the same proportions and conditions as skim milk, which were casein-lactose (CN-L) (1: 1.6) and casein-whey protein isolate-lactose (CN-WPI-L) (1: 0.2456: 1.579) models. These two models at different pHs (6.6, 8.0) and skim milk powder were treated in a microwave field at 400w for 15 min. Functional properties (solubility), structure, digestibility and antioxidant activities of casein-lactose Maillard reaction products were investigated. The results indicated that the digestibility of glycated milk proteins (CN-L) was higher than that of native protein. The improved solubility and enriched antioxidant peptide fraction showed that could be a promising method for dietary supplements. The fluorescence intensity was increased a lot, and environmental scanning electron microscope (ESEM) analysis showed that protein granule was changed from regular and smooth flaky to nubbly and amorphous structure. Then the results will have a great impact on the development of novel food structures with improved properties.