Fermentation Potentials of Baobab Pulp Extract in Soy Yoghurt Production

ABSTRACT

The study explored the use of baobab fruit pulp for natural fermentation and fortification of soy yoghurt. Pulp powder from Baobab ( Adansonia digitata L.), a deciduous tree of African Savannas, rich in phytochemicals and micronutrients, was adopted for the fermentation process. Soymilk was fermented with alternative starter culture (baobab pulp extract powder) to produce soy yoghurt, which was assessed for quality characteristics, with the baobab pulp added at varying percentages of (SB) 0.34, (SC) 0.52, (SD) 0.69 and (SE) 0.85 respectively, while a regular yoghurt‐producing starter culture was used for the control sample. Soy yoghurt samples produced were stored at ambient condition for 8 weeks and analysed using standard methods. The proximate composition (moisture, crude protein, fat, fibre, ash and carbohydrate), chemical properties (pH, TTA, vitamin C and viscosity), anti‐nutrients (phytate and cyanide), microbial loads (total fungal and total bacterial counts), as well as the sensory attributes were assessed. Comparing the treated samples with the control (SA), treated samples particularly SD and SE had significantly ( p  < 0.05) higher protein (12.28%–12.52%, 10.23%–10.67%), ash (1.67%–2.25%, 1.78%–2.22%), carbohydrate (0.43%–7.30%, 0.39%–5.09%), viscosity (402.30–405.50, 368.40–375.90 cP) and ascorbic acid (20.64–26.55, 18.61–24.27 mg/100 mL) throughout the storage period. However, during the storage period, moisture and pH significantly ( p  < 0.05) decreased, while titratable acidity increased in all samples. Beyond fortification, SE (a treated sample) recorded the lowest anti‐nutrient levels (Phytate and cyanide). During storage period, treated samples remained within permissible microbial limit. The control and sample fermented (SB) were not significantly different, and assessed as having better sensory qualities.