Microbiological, physico-chemical and sensory quality aspects of yoghurt enriched with Rosmarinus officinalis oil

Two types of yoghurt with Rosmarinus officinalis oil was prepared and stored up to 21 days. The extract plant was added at the rate of 0.14, 0.21, 0.29, and 0.36 g/L. Yoghurt samples were analyzed for some physical, chemical, microbiological and sensory some characteristics. The total and fecal coliform count, Staphylococcus aureus count, Salmonella count, yeast and mold counts were determined in yoghurt samples at two, seven and 21 days of storage period. There were significantly differences between the control and enriched yogurts in the dry matter, lactose, ash and protein contents. No germ detected in all samples during the storage period. Sensory analysis indicated that the highest flavour, taste and texture, of the two yoghurt types added was with 0.14g/L of essential oil among the yoghurts samples. Keywords : Yoghurt, Rosmarinus officinalis oil, physical, chemical, microbiological and sensory properties African Journal of Biotechnology Vol. 12(2), pp. 192-198