Formulation and Quality Evaluation of Yoghurts From Tigernut, Soybean and Cow Milk Blends

The high cost of dairy milk imports in many sub-Saharan African countries and growing consumer demand for health-promoting foods have fuelled interest in using plant-based milk for yoghurt production. This study examined the qualitative characteristics of yoghurts made from tigernut, soybean and cow milk blends, compared with 100% cow milk (skim milk) yoghurt as a control. Four distinct milk formulations were prepared using tigernut, soybean and cow milk in ratios of 80:20:10, 70:20:10, 60:20:20 and 50:30:20, respectively. These blends were then fermented with Lactobacillus bulgaricus and Streptococcus thermophilus to produce yoghurt from the combinations of tigernut, soybean and cow milk. Physicochemical properties, health-promoting potential, microbial analysis and sensory attributes were analysed over 14 days of refrigerated storage. Most parameters changed significantly over time, enhancing nutritional quality and health-promoting potential. Also, all the plant-based yoghurts showed superior health-promoting potential compared with the100% cow milk yoghurt. While 100% cow milk yoghurt had the highest overall acceptability, some formulations (80:20:10, 70:20:10 and 50:30:20) were well-accepted and even outperformed the control in certain sensory aspects. Given their cholesterol-free nature and antioxidant-rich bioactive compounds, tigernut and soybean milk can be viable dairy substitutes in yoghurt production.