Comparison of interaction, structure, and cell proliferation of α-lactalbumin–safflower yellow complex induced by microwave heating or conventional heating

Background The protein–polyphenol interaction mechanism has always been a research hotspot, but their interaction is affected by heat treatment, which is widely applied in food processing. Moreover, the effects of microwave or water-bath heating on the protein–polyphenol interaction mechanism have been not clarified. The pasteurization condition (65 °C, 30 min) was selected to compare the effects of microwave or water bath on binding behavior, structure, and cell proliferation between α -lactalbumin ( α -LA) and safflower yellow (SY), thus providing a guide for the selection of functional dairy processing conditions. Results Microwave heat treatment of α -LA–SY resulted in stronger fluorescence quenching than that of conventional heat treatment. Moreover, the binding constant K a of all α -LA–SY samples was augmented significantly after microwave or water bath treatment, and microwave-heated α -LA–SY showed the maximum K a . Fourier transform infrared spectroscopy showed that microwave heating resulted in more ordered structures of α -LA into its disordered structures than water bath heating. However, the ferric reducing antioxidant power and chroma value of α -LA–SY were more reduced by microwave heating than by water bath heating. Moreover, microwave heating facilitated the cell proliferation of α -LA–SY compared with water bath treatment. Conclusion It was demonstrated that microwave heating promoted interaction between α -LA and SY more than water bath heating did. Microwave heat treatment was a safe and effective way to enhance the binding affinity of α -LA to SY, being a potential application in food industry. © 2022 Society of Chemical Industry.