Physicochemical and structural properties of meat analogues from yeast and soy protein prepared via high-moisture extrusion

In this study, yeast and soy protein at different ratios (0:1, 1:9, 2:8, 3:7, 4:6, and 5:5) were used to produce meat analogues (MA) via high-moisture extrusion. According to color analysis, the addition of yeast protein (YP) increased the lightness of MA from 43.12 ± 0.26 (the control) to 50.37 ± 0.46 (50 g/100 g, dry basis). Textural results indicated that when the YP content was 40 g/100 g (dry basis), the hardness, chewiness, and fibrous degree of MA reached the maximum (523.94 ± 11.91 N, 724.55 ± 22.89 N, and 2.06 ± 0.15, respectively), which were higher than the control (419.63 ± 7.52 N, 618.02 ± 14.82 N, and 1.43 ± 0.03, respectively). Furthermore, YP increased the free water ratio, SS bond, and total β-sheets structure content, while reducing the β-turn structure content and thermal stability of MA. Overall, YP is a promising protein source for preparing high-quality MA.