CHAPTER ONE
INTRODUCTION
1.1 BACKGROUND INFORMATION
Milk is defined as a secretion of mammary gland of female animals. It is an exceptionally good source of protein which is of a high biological value in promoting the growth of children (ihekorany and Ngoddy, 1985). Milk is decribed as a good of outstanding interest, which is designed by nature to be complete good for very young mammals (fox and Cameron, 1980).
Milk contains a wide variety of constituents and contains most of the food factors associated with bacterial nutrition. Milk as a single food is of high nutritional value and is associated with spoilage microorganisms. At the time milk leaves the udder of the healthy cow, it contains few bacteria these stem from milk ducts and cistern. During the milking process, bacteria are usually added from various sources. In hand milking the sources are air the hair of the animal manure, the milkers equipment such as pails, feed and machine, most of these environmental factors are less important. However, the milking equipment may serve as an important source of contamination if it is not carefully cleaned and sanitized (ihekoronye and Ngoddy, 1985) .
After milk has been drawn it is rapidly cooled to 45 of prevent contaminants from multiplying. To eliminate pathogens from milk the process of pasteurization is applied. This involves application of heat below the boily point (fraizer and westhoff, 1978).
1.2 STATEMENT OF PROBLEM
Mike as a food of high nutritional value is highly associated with microorganisms. As a result of this contamination of raw milk, it not sterilized and taken directly or used for production of milk products, causes disease to man and also contribute to the spoilage of milk and milk products.
1.3 AIM AND OBJECTIVES OF THE STUDY.
AIM: The aim of the study is to evaluate the micro-flora of raw milk
Objectives: The objectives of the study are
i) To isolate and identify micro organisms that are contaminate raw milk.
ii) To determine of the milk is tubercle bacilli free
iii) To assay for the presence of coliform as an index of pathogens.
1.4 HYPOTHESIS
Ho: All fresh raw milk from healthy cows are free from marshal contamination both pathogenic and non- pathogenic
H1: All fresh raw milk from healthy cows are net free from microbial contamination both pathogenic and non- pathogenic.
1.5 JUSTIFICATION OF THE STUDY
Milk is know to be heavily contaminated by microorganisms if net properly handled. Therefore, there is a need to evaluate consumption or processing it for milk products
1.6 LIMITATION OF THE STUDY
This work is limited to bacterial organisms present in raw milk.
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