ISOLATION AND IDENTIFICATION OF MICROORGANISMS RESPONSIBLE FOR SPOILAGE OF DAIRY PRODUCT (MILK, YOGHURT AND LOCALY PREPARED CHEESE)

ABSTRACT

Milk, Yoghurt and Cheese are highly valuable food which are readily digested and have high concentration of nutrients which have proved to be a heaven of microbes, studies were conducted on the isolation and identification of microbes [Fungi and Bacteria] on peak canned milk, yoghurt, locally prepared cheese and cheese water. It was revealed that yoghurt was devoid of microbes while milk, locally prepared cheese and cheese water harboured microbes. Locally prepared cheeses, cheese water, yoghurt and peak canned milk samples were collected at Iloro market at Igbajo, Osun State, and the laboratory analysis was carried out at Microbiology Laboratory of College of Health Science, Ladoke Akintola University of Technology Oshogbo, Osun State. Potato Dextrose Agar, Nutrient Agar, MacConkey Agar, were used in culturing the samples to isolate and identify bacteria which includes; species of Klebsiella species, Candida albican, Pseudomonas aeruginosa. Milk contain bacteria contamination, Cheese and Cheese water contain fungi and bacteria contamination while Yoghurt was contamination free.

TABLE OF CONTENT

Certification                                                                                             i

Dedication                                                                                                         ii

Acknowledgement                                                                                  iii

Abstract                                                                                                     iv

Table of Content                                                                                               v - vi

CHAPTER ONE                                                                              1-4

1.0   Introduction                                                                                   1-2

1.1   Statement of the Problem                                                            2

1.2   Significance of the Study                                                              2

1.3   Scope of the Study                                                                         3

1.4   Objective of the Study                                                                            3

1.5   Limitation of the Study                                                                 4

CHAPTER TWO

2.0   Literature Review                                                                         5

2.1   The History of Milk                                                                       5-6

2.2   Sources of Milk                                                                               7-8

2.3   Evolution of Lactation                                                                  8

2.4   Types of Consumption                                                                  8-9

2.5   Composition Physical and Properties of Milk                          10-12

2.6   Spoilage of Milk                                                                                       13

2.7   Sources of Contamination of Milk                                              13-14

2.8   Infectious Microbes Found in Cow’s Milk                                 15-16

2.9   Acids Production by Microbes in Dairy Production Spoilage 17

2.10 Yoghurt                                                                                           18-20

2.11 The Benefits of Yogurt                                                                 19-20

2.12 Cheese                                                                                             20-22

CHAPTER THREE                                                                 23-28

3.0   Materials and Methods                                                                23-24

3.1  Methodology                                                                                    24-25

3.2  Inoculation Process to Detect Bacteria                                       25-27

3.3  Inoculation Process to Detect Fungi                                            27

3.4  Gram Staining                                                                                 28

CHAPTER FOUR                                                                   29-35

4.0   Result and Observation of the Isolated Specimen                            29

4.1   Colony Count of Isolated Microorganisms                                 30-31

4.2   Morphological & Biochemical Identification of

          Isolated Organisms                                                                       32-34

4.3   Discussions                                                                                     35

CHAPTER FIVE                                                                     36-39

5.0   Summary                                                                                        36

5.1   Recommendation                                                                           36-37

5.2   Conclusion                                                                                               37

5.3   References                                                                                               38-39