Effects of Nettle (Urtica dioica) Extract on Versus Pathogenic Microorganisms in Yogurt Production

Abstract

Contamination with pathogenic bacteria is the most common cause of foodborne illness and represents a public health problem worldwide. These pathogens can be controlled by adding extracts to fermented milk. In the present study, the effects of nettle extract on selected pathogenic bacteria in yogurt production were investigated. For this purpose, the antibacterial effectiveness of the extract additives in the presence of bacteria was examined and compared. Yoghurt samples, 24 different samples contaminated with 7 standard pathogen strains, were analyzed for chemical properties (pH and acidity) and antimicrobial activity after 1, 7, 14 and 21 days of storage at 4 °C. In particular, it was found that the decrease in pH and increase in acidity in the nettle extract samples after 21 days were significantly greater than in natural yogurt and yogurt samples containing nettle extract (0.5% and 1%, respectively) (p