Impact of Emulsifier Addition and Sterilization on the Physico-Chemical Stability of Tigernut-Date-Coconut Milk Beverage

Tigernut milk is valued for its nutritional benefits but often suffers from poor physical stability during storage, leading to starch sedimentation and undesirable flow properties that reduce consumer appeal. This study evaluated the effects of xanthan gum (0.1%), sodium caseinate (3%), and sterilization (121°C for 15 minutes) on the physicochemical stability and biochemical composition of tigernut milk and a tigernut-date-coconut milk blend (6:2:2). Key parameters assessed included viscosity, color (L*, a*, b*), sedimentation, pH, total titratable acidity (TTA), total soluble solids (TSS), and vitamin C content, both before and after sterilization. The results revealed that the unsterilized but stabilized tigernut-date-coconut milk (UTDCS) exhibited the best overall performance in terms of color retention, gravitational stability (sedimentation), total soluble solids (TSS), total titratable acidity (TTA), and viscosity, with no significant differences in the vitamin C content across all unsterilized samples. After sterilization, the blended samples (TDCS and TDC) showed the strongest and most distinct signals. Notably, all sterilized samples maintained excellent gravitational stability, with 100% creamy phase, whereas TDC showed the most suitable viscosity after sterilization. The findings indicate that hydrocolloids, protein-based stabilizers, and sterilization effectively enhance the quality and shelf-life of plant-based milk alternatives. This study advances the field of food technology by providing insights into formulation and processing strategies for developing functional, appealing, and stable tigernut-based beverages, while highlighting the need for further research on the impact of processing on nutrient bioavailability.