CONVENTIONAL AND PROBIOTIC YOGURTS DIFFER IN SENSORY PROPERTIES BUT NOT IN CONSUMERS' PREFERENCES

The objective of this work was to examine whether probiotic and conventional yogurts differ regarding their sensory properties and the consumers' preferences. Using quantitative descriptive analysis, 10 trained panelists evaluated the overall quality of yogurt samples over two sessions by rating the intensity of sensory descriptors on a 10-unit scale from commercially available plain full-fat conventional (6) and probiotic (3) yogurts, served in a randomized order. Consumers' preferences were determined by 50 untrained individuals applying the paired difference test for preference. Generally, the mean overall quality score of probiotic yogurt was significantly (P < 0.05) higher than one of the conventional products. This finding could be attributable to certain different properties of appearance (whey separation), texture (homogeneity, smoothness and thickness), taste/flavor (sweet and creamy) and aftertaste. Based on the results of descriptive sensory evaluation and the paired difference test, it appears that despite some observed differences in sensory properties, there were no significant differences in consumers' preferences between probiotic and conventional yogurt. PRACTICAL APPLICATIONS In the present study, it has been observed that among the investigated samples, yogurts with the higher overall sensory quality were probiotic. The probiotic samples showed significantly less distinctive syneresis, higher smoothness and were more homogenous than the conventional products. The mean intensity of sourness, but principally the sweet taste and creamy flavor was more distinctive in probiotic samples. The consumers' preference of probiotic and conventional yogurts evaluated by the paired difference test showed that the conventional product was preferred, but the difference was not statistically significant. It means that trained panelists differentiated conventional and probiotic yogurts in sensory properties, but there were no significant consumer-perceived differences between yogurts with and without probiotic culture.