The Effect of Heather Honey Addition on Physicochemical and Microbiological Properties of Stirred-Type Yoghurt

The aim of this study was to investigate the impact of the heather honey concentrations (2.5% and 5%) on the physicochemical and microbial properties of yoghurt samples made from cow milk. Honey, used as a natural fortifier, enhanced antioxidant activity and probiotic viability of experimental samples. Except for water activity (a_W), each physicochemical variable (dry matter, titratable acidity, water-holding capacity and anti-oxidant activity) differed significantly (p < 0.001) between the control and both experimental yoghurt sample groups (2.50% and 5.00%). Throughout the study, the 5.00% heather honey-added yoghurt consistently exhibited the peak antioxidant activity on days 1, 15, and 22. Multiple factor analysis (MFA) revealed correlations among the variables and visualised the similarity of the analysed samples on the 15^th and 22nd days. On the other hand, the results of MFA showed differences in control and both experimental yoghurt sample groups with heather honey addition. As the demand for fermented milk grows, the dairy industry is increasingly combining probiotics with functional foods—most notably through the development of probiotic functional yoghurts.