Effects of ultrasound‐assisted resting on the qualities of whole wheat dough sheets and noodles

Effect of ultrasound-assisted resting on the quality of surimi-wheat dough and noodles

In this study, the influence of ultrasound-assisted resting at different power on the rheological properties, water distribution and structural characteristics of dough with 50 % surimi as well as the texture, cooking and microstructure characteristics of the surimi-wheat noodles were investigated. Compared with the fermentation control (FC) noodles, the microstructure, cooking and texture characteristics of noodles (≤24.00 W/L) were significantly (p < 0.05) improved after ultrasonic treating. As the increasing of ultrasonic power, compared to FC, the creep strain, recovery strain, semi-bound water, and free sulfhydryl (SH) contents of surimi-wheat dough decreased at first and then increased significantly (p < 0.05). The α-helix and β-turn content of dough increased at first and then decreased after ultrasonic treatment, while the β-sheet was reversed. The surimi-wheat dough network structure was improved by ultrasonic treatment, with the densest and continuous pore size in 21.33 W/L, but the dough structure was broken and loose (>21.33 W/L), which consisted of the hardness, elasticity, chewiness, resistant and cooked quality of surimi-wheat noodles. This work elucidated the effect of ultrasonic power on the performance of surimi-wheat dough, and the optimal ultrasound power was obtained, thereby improving the nutritional properties and the quality of surimi-wheat noodles.

Investigating the positive effects of wrap-around resting on the qualities of semi-dried noodles through the quantitative analysis of gluten network

In this study, the dough sheet wrap-around was employed to assist the resting process of the semi-dried noodles comparatively with dough crumbs resting and common dough sheet resting. The gluten network quantitative analysis was carried out to investigate the positive impacts of dough sheet wrap-around resting in semi-dried noodles production. The results showed that the dough sheet wrap-around resting improved the color, surface smoothness, cooking qualities, and eating qualities of semi-dried noodles. Dough sheet wrap-around resting for 30 min significantly (p < 0.05) increased the surface smoothness and chewiness by 47.08% and 44.35%, respectively. Furthermore, increased extensibility in the transverse direction of dough sheets generated superior processing properties. The average protein length and width of dough sheets experienced a considerable (p < 0.05) reduction. In contrast, the branching rate was markedly (p < 0.05) augmented, which meant the distribution of gluten network was more uniform and denser. The total protein length and the number of protein network lines both significantly (p < 0.05) increased. The number of transverse protein network lines increased by 28.70%, which was much higher than that (5.77%) of the longitudinal direction. Conclusively, at the optimal dough sheet wrap-around time of 30 min, the higher-quality semi-dried noodles were produced by enhancing the gluten network.

Characterization of sonicated gluten protein and subsequent rheological properties of model dough and noodles

BACKGROUND

The present study aimed to investigate the effects of the thermo-mechanical and rheological properties of a wheat gluten-sonicated model dough and noodles, as well as the effects of ultrasonic frequency (20, 28, 40, 68 and 80 kHz) on the functional properties and structural features of gluten.

RESULTS

Water absorption, stability and developmental time, and viscoelastic behavior of gluten-sonicated model dough were all found to be improved. Water absorption, tensile resistance and stretching distance of noodles increased markedly, whereas cooking loss decreased. Ultrasonication at different frequencies also significantly affected gluten structure, including its surface hydrophobicity, micro-network structure, and secondary and tertiary structures. These alterations then caused changes in its functional characteristics. Compared to untreated gluten, sonicated gluten exhibited significantly increased oil and water capacities (8.75-15.26% and 100.65-127.71% higher than the untreated gluten, respectively), foaming and emulsifying properties, and increased solubility (63.46-98.83% higher than control). In addition, these findings indicated that 40 kHz was the likely resonance frequency of the cavitation bubble in the gluten solution. However, sodium dodecyl sulfate-polyacrylamide gel electrophoresis electropherograms revealed that such treatments did not affect the molecular weight of gluten, which was also consistent with its unchanged disulfide bond content.

CONCLUSION

The present study clarified the impact of frequency on the properties of gluten and model dough. The best frequency for modification of gluten was 40 kHz. Collectively, these findings suggest that ultrasonic technology has the potential for use in modifying wheat gluten and commercial noodle processing. © 2022 Society of Chemical Industry.