Trehalose-induced changes in the aggregation behavior and structural properties of wheat gluten

Trehalose is widely used in the food and cosmetics industry owing to its unique stabilizing properties. In this study, we aimed to further understand the effect of trehalose on the aggregation and structural properties of gluten. We investigated changes in the aggregation and textural properties, molecular weight distribution, disulfide bond contents, secondary structure, and network structure for weak-, middle-, and strong-gluten when supplemented with trehalose. The results showed that the macromolecular aggregation of gluten proteins was impaired. The hardness, gumminess, and chewiness of dough reduced, whereas adhesiveness increased significantly. Moreover, a looser gluten network structure was obtained with increase in trehalose content. High levels of trehalose (<5%) caused a decrease in the disulfide bond content. Secondary structure analysis of gluten indicated that the α-helix content increased for weak-gluten. In strong-gluten wheat, the β-sheet content was converted to random coil. This suggests that trehalose affected the hydration level of gluten. Trehalose likely competes with gluten for the available water by disrupting the hydrogen bonds between gluten and water molecules and breaking the ‘‘loop and train” model of gluten. Thus, the decreased disulfide bond content and increased α-helix and random coil contents induced by trehalose inhibited gluten aggregation and interrupted the gluten network. The study findings improve our understanding of trehalose functionality in dough of different gluten strength. Furthermore, these data provide valuable insights into the application of trehalose in wheat flour food products.