Thermal, rheological properties and microstructure of hydrated gluten as influenced by antifreeze protein from oat (Avena sativa L.)

This study examined the thermal, rheological properties and microstructure of hydrated gluten as influenced by oat antifreeze protein (AsAFP). The thermal properties of fresh hydrated gluten, including the melting temperature, freezing temperature, freezable water content and glass transition temperature, were determined. For hydrated gluten samples after freeze-thaw treatment, the change in melting performance and freezable water content were analyzed. The results showed that the addition of AsAFP increased the glass transition temperature and decrease the melting enthalpy and freezable water content of fresh hydrated gluten. The supplementation of AsAFP also influenced the melting performance of hydrated gluten after freeze-thaw treatment. The rheological properties showed that the addition of AsAFP inhibited the deterioration of the rheological properties of hydrated gluten. The secondary structure of the gluten proteins changed significantly, a-helix decreased and beta-sheet increased. The microstructure of the hydrated gluten demonstrated that supplementation with AsAFP may protect the gluten matrix from disruption during freeze-thaw cycles.