Microbiological Effects of Garlic Powder and Oregano Oil on Thick Yogurt during Production and Storage

Garlic powder and oregano oil are popular functional additives in fermented dairy foods. However, they are known to affect the titratable acidity and microbiological parameters of the finished product. The article describes the effect of these two components on starter culture during yogurt fermentation and on various microbiological processes during its storage. Using standard research methods, the authors determined the titratable acidity and viable cell count of starter microorganisms in yogurt during fermentation, as well as measured a set of microbiological parameters during storage at 4 ± 2 °C. The yoghurt samples fortified with 0.25, 0.50, 0.75, and 1.00% garlic powder and 0.50, 1.00, 1.50, and 2.00% oregano oil preserved their initial quality 15–20 beyond the standard storage time.