Physicochemical, Microbial, and Nutritional Evaluation of Tiger Nut Yogurt as a Plant-Based Alternative to...

The growing demand for plant-based dairy alternatives, driven by increasing lactose intolerance and dairy allergies, has sparked interest in underutilized crops such as tiger nut (Cyperus esculentus). This study assessed the physicochemical, microbial, and compositional properties of tiger nut yogurt with (TMYS) and without (TMYNS) starter culture, compared to conventional cow milk yogurt (CMY). The CMY exhibited the highest pH (4.87), while TMYNS showed greater acidity (pH 4.42). Tiger nut yogurts had significantly higher fat content (1.79%-1.88%) compared to CMY (1.08%), indicating their enhanced nutritional value. Total soluble solids were also slightly lower in tiger nut yogurts. Although microbial loads were higher in TMYS and TMYNS (up to 1.1 × 10⁵ CFU/mL), Escherichia coli was detected only in CMY and not in any of the tiger nut formulations. Yeast and coliforms were present across samples, but no mold contamination was observed. These findings highlight the potential of tiger nut yogurt as a safe and nutritious non-dairy alternative. The absence of E. coli in tiger nut-based yogurts, despite higher total microbial loads, is noteworthy and suggests better microbial safety. This study contributes novel insight by evaluating tiger nut as a functional yogurt base using both inoculated and spontaneous fermentation methods. However, further research is recommended to improve sensory appeal and extend shelf stability through optimized processing and packaging.