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Four phenolic acids [caffeic acid (CA), p-coumaric acid (p-CA), syringic acid (SA), and gallic acid (GA)] were selected and added to high-gluten wheat flour to investigate the effects of small molecule phenolic substances on the physicochemical properties of dough. Rapid viscometer was used to determine the pasting properties of the dough, Mixolab to determine the thermo-mechanical properties of the dough, rheometer to determine the rheological properties of the gluten proteins, and differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) to determine the thermodynamic properties of the gluten proteins. The results showed that the addition of p-CA at 0.1% was favorable for the dough to maintain a high termination viscosity (4 399 cp), and the addition of CA and SA inhibited the aging of starch. CA, p-CA, GA, and SA could significantly increase (P<0.05) the water absorption of dough and reduce the stabilization time, among which the highest water absorption of 63.08% was observed when 0.3% of GA was added. However, the addition of the four phenolic acids also led to the disruption of the rearrangement of starch molecules, which resulted in an increase in the degree of gelation. The overall viscoelasticity of gluten proteins was increased by the addition of CA, p-CA, GA, and SA, and all three phenolic acids, except p-CA, resulted in a decrease in the thermal stability of gluten proteins and a weakening of gluten strength. Finally, the microstructures of the doughs also showed that the addition of CA, p -CA, GA, and SA disrupted the originally homogeneous and dense microstructure of gluten proteins, and the extent of the disruption increased with the increase in the amount of phenolic acid added. [ABSTRACT FROM AUTHOR]

A uniaxial micro-electro-mechanical systems (MEMS) micro-vibration mirror can be used to construct a new type of fringe projection profilometry (FPP) system. In FPP system calibration, some pixels may be calibrated worse than other pixels due to various error sources, which will affect the final reconstruction accuracy. In addition, there are some difficulties in calibrating the MEMS-based system because a projector using the uniaxial vibration mirror does not have focusing optics and can only project unidirectional fringes. In this paper, we developed an FPP system using a uniaxial MEMS micro-vibration mirror. To solve the calibration problems, we propose a calibration model suitable for the MEMS-based system and a pixel refinement method. These pixels with relatively large calibration errors are called outlier-pixels, which will significantly increase the error of the following 3D mapping. Therefore, the pixel refinement method classifies all pixels based on a frequency distribution histogram of calibration errors during calibration and prevents outlier-pixels from participating in the following 3D mapping. The experimental results show that the proposed method can improve the accuracy of 3D reconstruction, and the feasibility of the self-developed system is verified.