The effects of non-thermal plasma (NTP) on the physicochemical properties of wheat flour and the quality of fresh wet noodles (FWN) were investigated. The results showed that NTP effectively decreased the total plate count (TPC), yeast and mould count (YMC) and Bacillus spp. in wheat flour. Wet gluten contents and the stability time reached the maximum when treated for 20 s. The viscosity of starch increased significantly after treatment due to the increased of damaged starch. The contents of secondary structure were altered to some extent, which was because that the ordered network structure of gluten protein broken. Furthermore, compared with the control, texture properties of FWN were enhanced significantly at 20 s, and the darkening rate of FWN was greatly inhibited due to the low polyphenol oxidase (PPO) activity. Consequently, the most suitable treatment was 500 W for 20 s, providing a basis for the application of NTP in flour products.

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Background and Objectives Pulsed light (PL) was first applied to the production of low bacterial wheat flour—treating wheat kernels with PL. The effect of PL on the physicochemical properties of wheat flour and the quality of fresh wet noodles (FWN) were investigated. Findings After treatment, the total plate count (TPC), yeast and mold count (YMC) in wheat flour decreased significantly. Wet gluten content and the stability time reached their maximums when the pulsed flash frequency was 10 c. Starch viscosity increased slightly, mainly due to an increase in damaged starch content. Secondary structures altered remarkably, which were consistent with changes in gluten protein microstructures. Moreover, the textural properties of FWN were improved greatly. Browning of FWN was significantly inhibited because of low polyphenol oxidase (PPO) activity in wheat flour. Conclusion PL was effective in decreasing the initial microorganisms in wheat flour as well as improving the quality of dough and FWN, and the optimum treatment was pulsed energy of 500 J, pulsed flash distance of 9 cm, and pulsed frequency of 10 c. Significance and Novelty These results showed that PL treatment could decrease TPC and YMC in wheat flour significantly, improve farinograph and pasting properties, change gluten protein microstructures and secondary structures, as well as improve textural properties of FWN and inhibit its darkening greatly, which provided a new method for low bacterial wheat flour production and promoted PL's industrialization.