The aim of the present study was to investigate the effects of supplements of pieces of walnuts without and with honey and hazelnuts on the count of lactic acid bacteria, dynamic of acidity, and the syneresis of yogurt. It was prepared yogurt from cow’s milk, supplemented by pieces of walnuts, without and with honey and hazelnuts. Our experimental results show that supplements reduced the time for coagulation with 2.3 to 15.7%, and slightly increased the titratable acidity of yogurt during the storage. All supplements lead to increasing of extracted milk serum and syneresis index during the storage. The highest effect was obtained from walnut + honey supplementation. Enrichment of milk with plant biologically active substances has positive effect on the microbial activity. Total count of lactic acid bacteria increased significantly at coagulum, almost twice – with the supplementation of walnut and hazelnut, and almost three times – with walnut plus honey.
I. Gospodinov, S. Chehlarova-Simeonova, A. Stoianova, R. Petkova