Figs. 3A and 4A show the chromatographic profiles of green and black tea samples, respectively, before the treatment with S. thermosphilus and L. bulgaricus yogurt bacteria. The chromatograms showed good separation of the six phenolic compounds allowing their identification and quantification easily with a predominance of GCG and EC. After the treatment of the same samples with the yogurt bacteria, the chromatograms obtained showed no significant modification (P < 0.05) of the phenolic compounds of both green and black tea samples (Figs. 3B and 4B. Table 1 gave the compositionof phenolic compounds in inoculated and non inoculated tea samples. The results obtained give a clear confirmation that the yogurt bacteria did not affect significantly (P < 0.05) the composition of the phenolic compounds of green and black teas. Before the beginning of production and storage trials, preliminary studies were conducted to see the effect of tea addition to milk on acidity during fermentation. The acidity of milks dropped as expected over the 6 h period of incubation and no significant of phenolic compounds in inoculated and non inoculated tea samples. The results obtained give a clear confirmation that the yogurt bacteria did not affect significantly (P < 0.05) the composition of the phenolic compounds of green and black teas. Before the beginning of production and storage trials, preliminary studies were conducted to see the effect of tea addition to milk on acidity during fermentation. The acidity of milks dropped as expected over the 6 h period of incubation and no significant(P < 0.05) differences (Fig. 5) in acidity were observed among the treatments, indicating that tea neither supported nor impeded lactic acid production by S. thermophilus and L. bulgaricus at this stage.