LIPIDS COMPOSITION IN THE EGG SHELL OF DOMESTIC FOWL

ABSTRACT

Poultry eggs are eaten in most areas of the world with fewer social taboos associated with them than pigs and cattle. The most commonly used bird eggs are those from chicken. In Nigeria, the domestic foul dominates the poultry industry. Of the 120 million indigenous poultry population in Nigeria, the domestic fowl constitutes about 91 % of this. For this reason, the present work tried to evaluate the nutritional levels of the lipid composition of the free-range fertilized cooked chicken eggs. Five eggs were involved in the study and they were collected at once. The following experimental procedures were carried out on the yolk and the albumen using standard analytical methods: crude fat determination, preparation of methyl esters and fatty acid analysis. Also determined was the quality assurance of the determinations to ensure their accuracies, calculation of uncertainty interval percentage (UIP) particularly for the fatty acid values.

TABLE OF CONTENTS vi

CHAPTER ONE

1.0 INTRODUCTION      1

1.1 PHYSICAL AND CHEMICAL CHARACTERIZATION OF EGG    2

1.2 STRUCTURE OF EGGS      3

1.3 NEW USE OF EGGS      4

1.4 NON-FOOD USES OF EGGS      4

1.5.0 USES OF PHOSVITIN       5

1.5.1 PHOSPHOPEPTIDES       5

1.5.2 USES OF PHOSPHOPEPTIDES        5

1.5.3 AIM AND OBJECTIVE        66

CHAPTER TWO

2.0 LITERATURE REVIEW         7

2.1 ANATOMY AND CHARACTERISTICS         8

2.2 STORAGE        12

2.3 PRESERVATION        13

2.3.1 NUTRITIONAL VALUE        14

2.3.2 HEALTH EFFECTS        16

2.3.3 CHOLESTEROL AND FAT        16

2.3.4 DIABETES        17

2.3.5 CONTAMINATION        18

2.4.0 LIPIDS         19

2.4.1 BIOLOGICAL ROLES OF LIPID        21

2.4.2 CLASSIFICATION OF LIPIDS        21

2.4.3 FATTY ACIDS        23

2.4.5 CLASSIFICATION OF FATTY ACIDS        25

2.4.6 ESSENTIAL AND NON ESSENTIAL FATTY ACIDS       26

CHAPTER THREE

3.1 MATERIALS AND METHODS        277

3.2 COLLECTION AND TREATMENT OF SAMPLES        27

3.3 CRUDE FAT DETERMINATION       28#

3.4 STEROL ANALYSIS       30

3.5 PHOPHOLIPIDS       32

3.6 QUALITY ASSURANCE       34

CHAPTER FOUR

4.0 RESULTS AND DISCUSSION       37

4.1 RESULT       37

4.2 DISCUSSION       43

CHAPTER FIVE

5.0 CONCLUSION AND RECCOMENDATION       48

5.1 CONCLUSION       48

5.2 RECCOMENDATION       48

REFRENCES       49