Abstract: The effects of adding different amounts of inulin on emulsification and thermal properties of wheat gluten protein were studied by differential scanning calorimetry and Fourier transform infrared spectroscopy. The protein structure was characterized by scanning electron microscopy. The results showed that inulin even at low concentration had a great effect on the emulsifying properties of wheat gluten. Inulin at a concentration of 10% increased the emulsifying activity index by 14.4%, and at 7.5% by 18.7%. Thermodynamic experiments showed that inulin increased the denaturation temperature and decreased the denaturation enthalpy of the protein. Inulin at a concentration of 12.5% increased the denaturation temperature. The structural analysis showed that the content of disulfide bond in the protein increased by 222% with the addition of 20% inulin. Moreover, the β-turn structure of the wheat protein was transformed into β-sheet and random coil structure in the presence of inulin. The gluten network structure became denser with inulin addition.

Key words: wheat gluten, inulin, emulsifying properties, thermodynamic properties, protein structure