## 3 Results and Discussion
### Organoleptic Evaluation  
The organoleptic evaluation showed that color and texture did not differ significantly among treatments (data not shown). Flavor (taste + odor) proved to be the most sensitive attribute in the evaluation of dessert yogurt quality. Table 5 shows flavor scores for both cow and goat dessert yogurts. Flavor scores for cow dessert yogurts ranged from 4.25 \(\pm\) 0.13 to 4.65 \(\pm\) 0.14 for the three cultures without the addition of _Bifidobacterium_ BB-12. Respective taste scores for samples with _Bifidobacterium_ BB-12 ranged from 4.06 \(\pm\) 0.15 and 4.20 \(\pm\) 0.10. The flavor of goat dessert yogurts ranged from 2.96 \(\pm\) 0.25 to 3.50 \(\pm\) 0.19 for the three cultures without the addition of _Lactobacillus acidophilus_. Respective flavor scores for samples with _Lactobacillus acidophilus_ LA-5 ranged from 3.70 \(\pm\) 0.15 to 4.25 \(\pm\) 0.20. Generally, it can be observed that cow dessert yogurts, without _Bifidobacterium_ BB-12 exhibited better flavor (\(p<\) 0.05) compared to those with _Bifidobacterium_ BB-12. In contrast, significantly higher (\(p<\) 0.05) flavor scores were recorded for goat dessert yogurts with _Lactobacillus acidophilus_ LA-5 compared to those without _Lactobacillus acidophilus_ LA-5. Between the cow dessert yogurts without _Bifidobacterium_ BB-12 and the goat dessert yogurts with _Lactobacillus acidophilus_ LA-5, the former were more acceptable (\(p<\) 0.05) by the panelists. Therefore, it can be concluded that the different types of milk, the specific starter cultures used, and the addition of probiotic bacterial strains has a considerable impact on the flavor of dessert yogurts. Within the cow dessert yogurts without _Bifidobacterium_ BB-12, the mild and classic starter culture recorded the highest flavor scores while within the goat dessert yogurts with _Lactobacillus acidophilus_ LA-5, the classic and acidic starter culture recorded the highest flavor scores. The organoleptic evaluation results in the form of a spider graph are shown in Figure 1. As can be seen, the optimum results for cow milk dessert yogurts were recorded in the cases of the mild and classic starter cultures without the addition of _Bifidobacterium_ BB-12, whereas in the case of goat milk dessert, the yogurt's optimum results were recorded in case of the classic and acidic starter cultures with the addition of _Lactobacillus acidophilus_ LA-5.  
In a study by [PERSON] et al. (2014), during the characterization of the sensory properties of traditional acidic and mild, less-acidic yogurts by a trained panel using a descriptive approach, it was observed that the important flavor differences found between the two samples of yogurt were mainly due to the differences in the acidity and not due to different concentrations of the three aroma compounds (acetaldehyde, 2,3-butanedione, and 2,3-pentanedione). This observation emphasizes the importance of acidity in yogurt flavor in relation to the contribution of various volatile compounds to the overall flavor of yogurt. Finally, [PERSON] et al., 2014 [PERSON] et al. (2014), when working with goat yogurt to which _Lactobacillus acidophilus_ LA-5 had been added, reported an improvement in goat yogurt acceptability with the addition of the probiotictic.