Microbial Contamination Of Yoghurt

Microbial Contamination Of Yoghurt

Chapter One

Preface

Yoghurt is a fermented dairy product attained from the lactic acid turmoil of milk. It’s one of the most popular instigated milk products in the world and produced commercially at home.( Willey etal., 2008). In its marketable product, non fat or low fat milk is pasteurized cooled to 43 ° c and are invested with known societies of microorganisms appertained to as starter societies. The starter societies may be a pure culture of a particular species of Lactobacillus or a mixed culture of Streptococcus thermophilus andLactobacillus bulgaricus in a 1 1 rate. The coccus which is theStreptococcus thermophilus grows faster than the Rod which is theLactobacillus bulgaricus and is primarily responsible for acid product while the rod adds flavor and aroma. The growth of these Microorganisms causes the metamorphosis 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 product at a rate lesser than that produced by them collectively.

Yoghurt is generally made from a standardized admixture containing whole milk, incompletely defatted milk, condensed skim milk cream and non fat dry milk. Alternately milk may be incompletely concentrated by junking of 15- 20 water in a vacuum visage or by heating. While the microorganisms stirring milk confers on it certain health benefits shy pasteurized milk may contain microorganism of special significance to man.( Boor and Murphy, 2002). In which its presence or absence in milk may reflect success or failure of good manufacturing practice( GMP) or beget infection when consumed together with food. This is of profitable significance in Africa where the HIV/ AIDS and cancer scourge has left the public who consume milk products vulnerable suppressed and prone to bacterial and fungi infection.( Boor, 2001).

Health complications associated with consumption of deficiently pasteurized milk products include serious infections that are hard, to treat with antibiotics. This becomes clinically significant if organisms insulated from an assessed sample is resistant to conventional antibiotics. therefore, can confer antibiotic resistance to the infected host while furnishing no indispensable medicine( Gould, 1994). Heat treated yoghurt don’t contain lactic acid bacteria as these are killed during post turmoil. Yoghurt manufacturing companies substantially request” heat treat” yoghurt to protract it’s shelf life( Hove et al, 1999). It’s important still to estimate the microbial graveness of some milk products vended in Nigeria. This design work aims at assessing the antimicrobial vulnerability pattern of microorganisms present in yoghurt vended in Enugu.