Structuring meat analogs by citrus fiber with reduced salt intake.

ABSTRACT

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.