Main Article Content
Physicochemical and sensory characteristics of yoghurt produce from ewe milk, goat milk and a mixture of ewe and goat milk
Abstract
Objective: To evaluate the physicochemical and sensory acceptability of yoghurt produced from ewe, goat and a mixture of ewe milk and goat milk in Nigeria in order for the populace to harness the nutritional and therapeutic benefits of the milks.
Methods: Samples of whole cow milk (WCM) as standard, goat milk (GM), ewe milk (EM) and mixture of goat milk and ewe milk (GM/EM) in 1:1 (v/v) ratio, obtained from a local dairy farm were used for yoghurt production. The milk samples were each pasteurized, inoculated with 5g/l of mixed cultures of L. bulgaricus and S. thermophilus, fermented for 4h at 45oC, homogenized, before sugar and gelatin were added. The yoghurt samples were packed into sterile 200ml air tight plastic container, stored at 0oC for 24h and assayed for pH, titratable acidity, proximate composition, zinc, mg, Fe, Cu and sensory characteristics.
Results: The yoghurt samples produced from GM, EM, and GM/EM had significantly (P<0.03) higher values for fat ash, pH, and mineral elements (Fe, Cu), total solids, than the WCM. The protein content of yoghurt from EM and GM/EM samples were significantly higher (P<0.05) then the WCM. The yoghurt produced from EM and GM/EM were comparable in all the parameters tested and were significantly (P<0.05) rated higher than those of yoghurts produced from WCM and GM, except for color in the case of GM.
Conclusion: GM, EM and GM/EM (1:1 v/v) yoghurt samples had comparable organoleptic rating to the WCM (standard) sample. However, the best rating was obtained for GM/EM and EM yoghurts in terms overall acceptability. Therefore, yoghurt produced from either equal portions of GM/EM or from EM milk would be acceptable to Nigerian consumers such that the nutritional and therapeutic benefits of the milks would be available to the populace.
Key words: Physicochemical and sensory characteristics, yoghurts ewe milk, goat milk, whole cow milk.
Methods: Samples of whole cow milk (WCM) as standard, goat milk (GM), ewe milk (EM) and mixture of goat milk and ewe milk (GM/EM) in 1:1 (v/v) ratio, obtained from a local dairy farm were used for yoghurt production. The milk samples were each pasteurized, inoculated with 5g/l of mixed cultures of L. bulgaricus and S. thermophilus, fermented for 4h at 45oC, homogenized, before sugar and gelatin were added. The yoghurt samples were packed into sterile 200ml air tight plastic container, stored at 0oC for 24h and assayed for pH, titratable acidity, proximate composition, zinc, mg, Fe, Cu and sensory characteristics.
Results: The yoghurt samples produced from GM, EM, and GM/EM had significantly (P<0.03) higher values for fat ash, pH, and mineral elements (Fe, Cu), total solids, than the WCM. The protein content of yoghurt from EM and GM/EM samples were significantly higher (P<0.05) then the WCM. The yoghurt produced from EM and GM/EM were comparable in all the parameters tested and were significantly (P<0.05) rated higher than those of yoghurts produced from WCM and GM, except for color in the case of GM.
Conclusion: GM, EM and GM/EM (1:1 v/v) yoghurt samples had comparable organoleptic rating to the WCM (standard) sample. However, the best rating was obtained for GM/EM and EM yoghurts in terms overall acceptability. Therefore, yoghurt produced from either equal portions of GM/EM or from EM milk would be acceptable to Nigerian consumers such that the nutritional and therapeutic benefits of the milks would be available to the populace.
Key words: Physicochemical and sensory characteristics, yoghurts ewe milk, goat milk, whole cow milk.
