Incorporation of Commercial and Agglomerated <i>Spirulina platensis</i> Powder in Yogurt: Effect on Rheology, Texture, Color, and Sensory Properties

This study evaluated the rheological and sensory properties of yogurts incorporated with commercial and fluidized-bed agglomerated with maltodextrin Spirulina platensis powders at concentrations of 0.5–2.0% (w/w). Yogurts containing the agglomerated powder showed significantly higher apparent viscosity (p < 0.05) than those with the commercial powder. According to the Herschel-Bulkley model, the agglomerated formulations exhibited higher consistency indexes (K, 2.50–3.30 Pa·sn) and shear stress coefficients (τ0, 1.57–1.86 Pa) but lower flow behavior indexes (n, 0.16–0.41), indicating yogurts with greater consistency and creaminess compared to the control formulations and those incorporated with the commercial powder (p < 0.05). Texture analysis corroborated these findings: hardness and consistency increased significantly in yogurts with the agglomerated S. platensis (0.69–1.02 N and 13.11–19.66 N·s, respectively), whereas cohesiveness (−0.82 to −0.59 N) and viscosity index (−1.145 to −0.954 N·s) remained comparable to the control (p < 0.05). Regarding color, yogurts became darker with a characteristic bluish-green hue, more intense in those containing the agglomerated powder. For sensory analysis, the evaluation showed that yogurts containing up to 1.5% agglomerated S. platensis achieved acceptance similar to the control, whereas for the commercial powder, similarity occurred only at 0.5%. Overall, the agglomeration technique proved effective in improving the dispersion and homogeneity of cyanobacteria in yogurt, positively influencing its rheological and sensory properties.