This study was carried out to enumerate the microbial loads in pasteurized bottled milk drinks. The microbial load was determined by serial dilution and spread plate techniques while the isolation and identification of Bacillus species was done using Mannitol Yolk Polymyxin and conventional biochemical methods. Four out of the nine products sampled had no microbial growth while the remaining five had total viable count that ranged from 8.0 x 106 to 1.32 x 107 cfu/ml. The highest load was discovered in BBStar while the lowest microbial load was discovered in Bobo. Five species of Bacillus were isolated out of which four were Bacillus cereus and one were Bacillus subtilis. The high microbial load and isolation of Bacillus species in these pasteurized milk drinks pose a major threat to consumers of these products.
TABLE OF CONTENTS
CHAPTER ONE
1.1 Introduction
1.2 Aim of the Study
1.3 Specific Objectives
CHAPTER TWO: LITERATURE REVIEW
2.1 The Genus Bacillus
2.1.1 The Bacillus cereus Group
2.1.2 The Bacillus subtilis Group
2.2 Pathogenic and Toxigenic Characteristics
2.3 Effects of Bacillus species on Human Health
2.4 Incidence of Bacillus Species from Milk Products
2.5 Spoilage of Fluid Milk Products
2.6 Prevention and Control Measures
2.6.1 Prevention of Spoilage in Milk
CHAPTER THREE: MATERIALS AND METHOD
3.1 Collection of Samples
3.2 Sterilization of Glass wares
3.3 Preparation of Media
3.4 Isolation of Bacillus Species
3.5 Identification and Characterization of Bacillus spp.
3.5.1 Gram Staining
3.5.2 Catalase Test
3.5.3 Oxidase Test
3.5.4 Motility
3.5.5 Kligler Iron Agar Test
CHAPTER FOUR: RESULTS
CHAPTER FIVE
5.1 Discussion
5.2 Conclusion and Recommendations
REFERENCES
LIST OF TABLES
4.1 Total Bacterial Count of Milk Drinks
4.2 Biochemical Characterization of Isolates
4.3 Frequency and Percentage of Occurrence of Isolated Organisms from Milk Samples
