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In this study, we investigated the effect of addition of citrus fiber (CF; 5% and 10%, which consists mainly of soluble pectin and insoluble cellulose) on physical properties and microstructure of meat analogs based on soy protein isolate and wheat gluten using high‐moisture extrusion. Layered structure or microstructure of meat analogs was observed by scanning electron microscope and confocal laser scanning microscope. Compared to the control (without CF), meat analogs with CF addition showed disorder layered microstructure, which was interconnected with smaller fibers. Rheological measurements (strain sweep and frequency sweep) show that the incorporation of CF resulted in meat analogs with softer texture. The moisture content of meat analogs increased significantly upon the addition of CF, which was also correlated with juiciness. Sensory evaluation and dynamic salt release results confirm that the saltiness of meat analogs with CF addition was enhanced due to the structural changes of phase‐separated structures, achieving salt reduction by 20% and showing a saltiness similar to the control sample. This research provides a novel approach to modulate the saltiness perception of meat analogs by modifying the phase separation of protein/polysaccharides. Practical Application: Citrus fiber is added to the plant protein matrix to prepare meat analogs with high moisture content and enhanced saltiness perception via modifying the phase separation of protein/polysaccharides. This work provided a potential target for the meat industry to produce the meat analogs with less salt intake. Further research can be conducted using modified fibrous or inner structure of meat analogs to improve its quality. [ABSTRACT FROM AUTHOR]

Effect of tea polyphenols (TP) on the quality of Chinese steamed bun (CSB) was investigated, while the interaction and action mechanism between TP and vital wheat gluten (VWG, constitutive proteins of flour) were further explored. With a low concentration (1%) of TP, CSB showed positive changes in quality, and the hardness of CSB decreased by 33.95%, while its specific volume, springiness, and resilience separately increased by 1.8%, 11.9%, and 5.5%, whereas the higher concentrations of TP (2% and 4%) caused an adverse impact. By observation of scanning electron microscope, VWG formed a fluffier structure with a low concentration of TP, while the structure deteriorated at high concentration of TP. In addition, the secondary and tertiary structures of VWG were both changed by TP. Along with the results of thermodynamic analysis (thermogravimetric and differential scanning calorimetry measurements), TP could induce the structural rearrangement of VWG. Further, a lower amidogen and sulfhydryl contents of VWG were obtained in TP groups, which illustrated that peptide and disulfide bonds of VWG were not possibly interrupted by TP. Instead, hydrophobic residues of VWG were bonded to form a more hydrophilic structure. Moreover, according to molecular docking results, epigallocatechin‐3‐gallate interacted tightly with VWG by hydrogen bonds and hydrophobic actions, and the action sites were mainly at hydrophobic and hydrophilic residues. All results suggested that the VWG structure was affected greatly by TP, and a low dose of TP might be potential to improve the quality of flour products. Practical Application: The physicochemical properties of gluten show the significant effects on the quality of flour products in food industry. In the present study, a low dose of tea polyphenols exhibited a strengthened effect on gluten, so as to ameliorate the texture of Chinese steamed bun (CSB) due to their tight interactions with gluten, while the color of CSB was changed to brown as tea polyphenols. All results suggested that a low dose of tea polyphenols could be potentially utilized to improve flour quality and enhance gluten strength in food industry. [ABSTRACT FROM AUTHOR]