Ready to eat local fried yam and potato snack is prepared with yam and potato, seasoned with pepper and salt. It is mostly taken by large numbers of itinerary workers and students in the environment. Ten samples each of fried yam and fried potato were purchased from ten different retailers in Ijebu-North Local Government Area in Ogun State. Each sample was analyzed to determine the pH and microbial quality. Decimal serial dilutions were prepared and then plated on nutrient agar, Mac Conkey agar and potato dextrose agar. The pH range of fried yam and fried potato were 6.0 – 6.5 and 6.0 – 6.8 respectively. Seven microorganisms were recovered from the samples namely: Staphylococcus aureus, Bacillus cereus, Escherichia coli, Aspergillus sp., Fusarium sp., Rhizhopus sp., and Candida sp. The bacterial counts ranged between 1.2 x 104 and 3.41 x 106 while the fungi counts ranged between 1 X 104 and 2.1 x 105. Due to high level of microbial load and popularity of the snack with itinerary workers and students, there is need to proper handling of the snack with good hygiene.
TABLE OF CONTENTS
Chapter One: Introduction
1.0 Background to the Study
1.1 Aim and Objectives
1.2 Justification
Chapter Two: Literature Review
2.1 Yam and its origin
2.1.2 Morphology of Yam
2.1.3 Yam structure
2.1.4 Yam storage
2.1.5 Chemical and Nutritional Composition of Yams
2.2 Sweet Potato
2.2.1 Crop Uses
2.2.2 Crop Description
2.3 Diseases and Pest
2.3.1 Virus Diseases
2.3.2 Nematodes
2.3.3 Insects
2.4 Harvesting, Curing and Storage
2.4.1 Harvesting
2.4.2 Curing and Storage
2.5 Potato Chemical Composition
2.6 Specific Gravity and Dry Matter
2.7 Yam and Potato chip frying
2.8 Yam and Potato Frying Temperature and Time
Chapter Three
Material and Methods
3.1 Collection of Samples
3.2 Sterilization of Apparatus
3.3 pH Determination
3.4 Media
3.5 Serial dilution
3.6 Isolation of Microbes
3.7 Purification of the Isolates
3.8 Identification of Isolates
3.9 Biochemical Reaction
Chapter Four: Results
4.1 Isolates from the Samples
Chapter Five: Discussion and Conclusion
5.1. Discussion
5.2 Recommendation
References
LIST OF TABLES
2.1 Chemical composition of potato tubers (Leszcyftski, 1989)
4.1 Determination of PH Level
4.2 Microbial Load of Fried Yam and Fried Potato Samples
4.3 Microorganisms isolated from Fried Yam and Fried Potato Samples
4.4 Colonial morphology and microscopic features of fungi isolated
4.5 Morphological and biochemical characteristics of bacteria isolate
4.6 Percentage of occurrence of bacteria
4.7 Percentage of occurrence of fungi
