Structural, Physicochemical, and Sensory Implications of Progressive Sodium Reduction with Nutritional Yeast in Cooked Sausages

Excessive sodium intake is a public health concern, although sodium chloride is technologically essential in comminuted meat systems due to its role in protein solubilization, water binding, and gel formation. This study evaluated the extent to which progressive sodium reduction combined with nutritional yeast supplementation preserves physicochemical stability, structural integrity, and sensory quality in cooked sausages. Four formulations were produced: a referent and three reduced-salt (NaCl) treatments (−15%, −25%, −35%) containing 2% nutritional yeast (1% in the referent). Water activity increased significantly with salt reduction (0.969–0.977; p < 0.05), accompanied by higher lightness (CIE L*) and yellowness (CIE b*), whereas instrumental redness (CIE a*) remained stable. Proximate composition was unaffected except for the expected decrease in ash and salt content (p < 0.05), while free glutamic acid increased significantly in reduced-salt treatments (0.67 vs. 0.87–0.91 g/kg; p < 0.05). Instrumental texture parameters indicated preserved cutting resistance, although repeated compression revealed reduced structural resilience at the 35% reduction level. Sensory evaluation showed that reductions up to 25% maintained overall typicality and balance, whereas 35% reduction decreased saltiness, slice coherence, aroma harmony, and texture typicality (p < 0.05). Principal component analysis confirmed a multivariate shift from a salt-stabilized structural domain to a softer, yeast-associated sensory domain at the highest reduction level. Moderate sodium reduction combined with nutritional yeast is therefore technologically and sensorially feasible in this product category.