Abstract

Increasing awareness of health benefits of plant-based food/drinks has resulted in increased preference of consumers for functional beverages as compared to conventional sugar-laden drinks/beverages which only quench thirst but provide little or no nutritional or health benefits. However, most commercially-available functional drinks/beverages are often expensive and not affordable for most people especially low-income earners in developing countries. This study aims to develop low-cost functional yoghurt from milk-cocoa powder blends so as to provide alternative to expensive commercially-available functional drinks and enhance direct consumption of bioactive-rich cocoa powder. Cocoa powder was used to partially replace milk in yoghurt at levels of 10-50%. Standard procedures were used to evaluate triplicate samples of yoghurts for proximate and mineral composition, vitamins, radical-scavenging abilities and phenolic content. Sensory attributes of the yoghurts were evaluated using trained and untrained panels. pH, acidity and brix ranged from 4.29-4.34, 0.67-0.88% and 12-13.5%, respectively. Cocoa powder inclusion significantly increased crude protein (33.7-38.89% DW), fat (0.07-0.14%), ash (0.71-1.01%), fibre (0.1-0.21%), Ca, Mg, K, Zn, Fe, vitamins A, B₁, B₂, B₃, C and E; while vitamin D reduced from 1.64 to 0.72-1.08 mg/L. Similarly phenolic and flavonoid contents, DPPH, FRAP and ABTS increased; values ranged from 0.03-0.16 mg/gGAE; 0.03-0.06 mg/gQUE, 40.12-72.72%, 0.43-1.17 mg/g and 22.49-26.09 mmol/ml, respectively. While the trained panel preferred 50:50 milk-cocoa yoghurt, untrained panel preferred 90:10 milk-cocoa yoghurt, indicating both panels’ preference for milk-cocoa yoghurts as compared to the plain yoghurt. Organoleptically acceptable, nutritionally-rich, low-cost functional yoghurt high in bioactive compounds can be developed from milk and cocoa powder. Its production requires no sophisticated machines since yoghurt is already being produced by both rural and urban dwellers/processors in Nigeria. This milk-cocoa yoghurt provides a cheaper alternative not only packed with bioactive compounds from cocoa powder but also high in protein and micro and macronutrients.

Key words: Antioxidant, cocoa, fermented milks, functional foods, Nigeria, radical-scavenging activity, trained panel, yoghurt.