COMPARATIVE ANALYSIS OF PHYSICO-CHEMICAL, ORGANOLEPTIC PROPERTIES AND PROXIMATE COMPOSITION OF FRESH COW MILK AND TIGER NUT YOGHURTS

Abstract

ABSTRACT Yoghurt is a dairy product produced by bacteria fermentation of milk sugar (lactose) into lactic acid, which gives yoghurt its gel-like texture and characteristics taste. Five groups of Yoghurts were produced from fresh cow milk and tiger nut milk (100%CM, 100%TG, 70-30%CMTG, 50-50%CMTG, 30-70%CMTG). The Physico-chemical, Organoleptic properties and Proximate compositions of the yoghurts were comparatively analyzed. Minerals (sodium, potassium, calcium, magnesium and phosphorus) were analyzed using flame photometer. pH and temperature was determined; while the antioxidant vitamins A, C and E was analyzed spectrophotometrically. Lactose, Fat, Crude Protein, Carbohydrate, Moisture and Ash Contents determined. The results shows that 50-50% CM TG had the highest Vitamin A and 30-70% CM TG had the lowest. Concentration of Vitamin C was higher in 30-70% CM TG and lower in 100% CM. Vitamin E Concentration was higher in 100% CM and lower in 50-50% CM TG. No significant (p<0.05) difference observed for temperature in all yoghurts samples. Yoghurts PH was significantly low and acidic. Lactose concentration was higher in 70-30% CMTG and lower in 50-50% CMTG. Fat and Protein concentration was higher in 100% CM and lower in 30-70% CMTG. Sodium concentration was higher in 100% CM and lower 100% TG. Potassium concentration was higher in 70-30% CM TG and lower in 100% CM. Calcium concentration was higher in 100% CM, lower in 100% TG and 30-70% CM TG. No significant (p<0.05) difference observed in Magnesium. Phosphorous concentration was higher in 70-30% CM TG and lower in 50-50% CMTG. Organoleptic properties; taste of 50-50% scored higher and 30-70% CMTG scored lower. Aroma of 70-30% CMTG scored higher and 30-70% CMTG scored lower. Nitrogen concentration was higher in 100% CM and lower in 30-70% CMTG. No significant (p<0.05) difference in Ash and Moisture. Carbohydrate concentration was higher in 100% TG and lower in 100% CM. Sensory evaluation indicated that cow milk yogurt blended with Tiger nut had the overall acceptability compared to that of whole cow milk and whole tiger nut alone.