The physicochemical property of native buckwheat starch (BWS) limits the application, which attracts more attention in the food industry. The objective of this study was to investigate the effects of different ultrasonic powers combined with moisture contents on the structure and physicochemical properties of BWS. The results showed that ultrasonic treatment significantly reduced the gel hardness and loss modulus of BWS. The increase in water content during ultrasound effectively enhanced the swelling power of BWS and reduced the peak viscosity. Besides, with the increase of water content and ultrasonic power, the crystallinity of BWS decreased significantly, and the formation of ordered structures was suppressed. In addition, after ultrasonic treatment, the particle size of BWS was decreased, and the surface became rough and concave. In short, ultrasonic treatment effectively improves the processability of BWS and provides a new theoretical basis for physical treatment in the production of cereal starch.

Frozen dough is suitable for industrial cold chain transportation, but usually experiences temperature fluctuations through the cold chain to the store after being refrigerated in a factory, seriously damaging the product yield. In order to analyze the influence mechanism of temperature fluctuation during the terminal cold chain on frozen dough, the effects of terminal freezing and thawing (TFT) on the quality (texture and rheology) and component (water, starch, protein) behaviors of dough were investigated. Results showed that the TFT treatment significantly increased the hardness and decreased the springiness of dough and that the storage modules were also reduced. Furthermore, TFT increased the content of freezable water and reduced the bound water with increased migration. Additionally, the peak viscosity and breakdown value after TFT with the increased number of cycles were also increased. Moreover, the protein characteristics showed that the low-molecular-weight region and the β-sheet in the gluten secondary structure after the TFT treatment were increased, which was confirmed by the increased number of free sulfhydryl groups. Microstructure results showed that pores and loose connection were observed during the TFT treatment. In conclusion, the theoretical support was provided for understanding and eliminating the influence of the terminal nodes in a cold chain.