Project Abstract

Abstract
Yoghurt is a popular fermented dairy product consumed worldwide and is known for its nutritional benefits. However, the presence of microorganisms in yoghurt raises concerns about potential health risks, especially when these microorganisms exhibit antimicrobial resistance. This study aimed to assess the antimicrobial susceptibility pattern of microorganisms present in yoghurt. A total of 100 yoghurt samples from different brands and sources were collected and analyzed for the presence of various microorganisms, including bacteria and fungi. The samples were processed using standard microbiological techniques to isolate and identify the microbial species present. Antimicrobial susceptibility testing was then performed on the isolated microorganisms using the disc diffusion method. The results revealed the presence of a diverse range of microorganisms in the yoghurt samples, including common bacteria such as Lactobacillus, Streptococcus, and Enterococcus species, as well as fungi such as Saccharomyces and Candida species. Antimicrobial susceptibility testing showed varying patterns of resistance among the isolated microorganisms. Some species exhibited resistance to multiple antimicrobial agents, including commonly used antibiotics such as penicillin, tetracycline, and erythromycin. Furthermore, the study found differences in antimicrobial susceptibility patterns among yoghurt samples from different brands and sources. Some samples showed higher levels of antimicrobial resistance compared to others, indicating potential differences in the microbial composition and antimicrobial exposure during production and storage. These findings underscore the importance of monitoring the antimicrobial susceptibility of microorganisms present in yoghurt to ensure food safety and public health. The presence of antimicrobial-resistant microorganisms in yoghurt raises concerns about the potential transmission of resistance genes to consumers and highlights the need for stringent quality control measures in dairy production. In conclusion, this study provides valuable insights into the antimicrobial susceptibility patterns of microorganisms present in yoghurt. Further research is needed to investigate the factors contributing to antimicrobial resistance in yoghurt microorganisms and to develop strategies to mitigate the risks associated with antimicrobial resistance in dairy products.

Project Overview

1.0   INTRODUCTION

Yoghurt is a fermented dairy product obtained from the lactic acid fermentation of milk. It is one of the most popular fermented milk products in the world and produced commercially at home. (Willey et al., 2008). In its commercial production, non fat or low fat milk is pasteurized cooled to 43°c and are inoculated with known cultures of microorganisms referred to as starter cultures. The starter cultures may be a pure culture of a particular species of Lactobacillus or a mixed culture of Streptococcus thermophilus and Lactobacillus bulgaricus in a 1: 1 ratio. The coccus which is theStreptococcus thermophilus grows faster than the Rod which is the Lactobacillus bulgaricus and is primarily responsible for acid production while the rod adds flavor and aroma. The growth of these Microorganisms causes the transformation of milk’s sugar, lactose into lactic acid. This process gives yoghurt it’s texture. The associative growth of the two organisms results in acid production at a rate greater than that produced by them individually.

Yoghurt is generally made from a standardized mixture containing whole milk, partially defatted milk, condensed skim milk cream and non fat dry milk. Alternatively milk may be partly concentrated by removal of 15- 20% water in a vacuum pan or by heating. While the microorganisms fermenting milk confers on it certain health benefits inadequate pasteurized milk may contain microorganism of special importance to man. (Boor and Murphy, 2002).