Lactobacillus delbrueckii ssp. bulgaricus, an important species of lactic acid bacteria, is widely used in the dairy industry, particularly in yogurt production. Commonly used in mixed cultures and especially with Streptococcus thermophilus, L. bulgaricus is mandatory for traditional yogurt and also confers several health benefits that meet the prerequisites for probiotic bacteria. The current standard medium, de Man, Rogosa and Sharpe (MRS), is unreliable as a selective method for isolating L. bulgarcius species from different sources including dairy products. MRS can also present a false positive for L. bulgaricus in some dairy products due to the presence of high background colonies of similar species. Consequently, there is a need for a better, more reliable medium for the differential enumeration of L. bulgaricus. The objective of this study was thus to formulate an agar medium that is effective for the differential isolation and enumeration of L. bulgaricus. A modified reinforced clostridial medium (mRCM) was formulated by adding 0.025% CaCl₂, 0.01% uracil, 0.2% Tween 80, 0.5% fructose, 0.5% dextrose, 1% maltose and 0.25% pyruvate to RCM. The inclusion of 0.04% aniline blue dye in the mix influenced the improved morphology and differentiation of the L. bulgaricus colonies observed in the mixed yogurt culture. The cell recovery and bacterial counts for L. bulgaricus in the tested yogurt brands using mRCM-BLUE were significantly higher than those found in the standard MRS medium as mRCM-BLUE largely inhibited the growth of other bacterial species (Streptococcus thermophilus, Lactobacillus acidophilus, Bifidus and Lactobacillus reuteri) present in the yogurt. Our results thus suggest that mRCM-BLUE could be recommended as a selective agar medium for more accurate differentiation and enumeration of L. bulgaricus in dairy products.