Effects of Ball-milled Yeast Protein on the Quality Properties of Fresh Noodle

To investigate the effects of ball milling (BM) treated of yeast protein (YP) on the quality properties of fresh noodles, YP powder samples were processed using a planetary ball mill under different conditions (100 r/min for 10 and 40 min, and 500 r/min for 10 and 40 min). The resulting BM-treated YP samples were characterized for their morphology, color, and particle size. These treated YP were then incorporated into wheat flour to prepare fresh noodles, and the appearance, microstructure, cooking properties, texture, sensory attributes, and digestibility of the YP noodles were systematically characterized. The results showed that untreated YP consisted of large, irregular spherical particles with a D_4,3 of 42.26 μm. In contrast, the YP sample treated at 500 r/min for 40 min exhibited finer, irregular particles, with a significant reduction in D_4,3 to 5.04 μm (P<0.05). Compared to the control group, the direct addition of untreated YP led to a decline in all noodle quality parameters. However, as the BM energy input increased, the quality of YP noodles gradually improved. Specifically, compared to noodles with untreated YP, noodles containing YP ball-milled at 500 r/min for 40 min demonstrated a color shift from dark yellow to light yellow, a continuous and dense gluten network microstructure, reduced water absorption (from 64.91% to 61.19%) and cooking loss (from 3.30% to 3.05%), increased firmness (from 2.656 N to 2.967 N) and chewiness (from 2.923 J to 3.600 J), and a decreased starch digestibility (from 67.3% to 63.1%). Moreover, these noodles achieved higher sensory scores, characterized by a more elastic texture, smoother surface, and better color acceptance. In conclusion, BM treatment enhanced the applicability of YP in noodles and improved their overall quality. This study provides a theoretical basis for the application of YP in the food industry and offers new insights for developing functional noodle products.