Abstract
In this experiment, the conjugation reaction between gluten and maltose via Maillard reaction under dry-heated condition was studied. The process conditions for the preparation of protein-maltose conjugates with optimum solubility were optimized by using Box-Behnken model. The conjugation reaction and the structure changes of the protein-maltose conjugates were confirmed by infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The results showed that the process conditions for the preparation of protein-maltose conjugates with optimum solubility were as follows: temperature 50.72°C, time 1.92 days, and gluten/maltose (W/W) 267.36%. The infrared spectroscopy showed that the structure of the modified protein had a very obvious change, including the decrease in β-fold and β-turn and the increase in α-helix at a certain degree. But the conjugation reaction has little effect on the irregular coiled structure. The scanning electron microscopy showed that the microstructure of gluten is small grainy, but gluten-maltose conjugate looks sheet with bigger volume.