ABSTRACT

Sweet potato tubers (peeled) were examined for ethanol production and biomass. The sweet potato tubers were grinded and hydrolysed/saccharified enzymatically using Trichoderma viride which resulted to a sugar yield of 7.2%brix and was optimized to 22.4% for fermentation to occur.Sacccharomycescerevisae from palm wine was used to ferment the hydrolysate to produce alcohol. During the fermentation process, records shows that the specific gravity,pH and sugar content reduced.The sugar reduced from 12.4% to 1.64%,The specific gravity reduced from 1.127g/cm3 to 1.016g/cm3  and the pH reduced from 6.0 to 3.1.The acidity increased from 0.24% to 1.53% and the alcohol content increased from 1.16% to 11.86%V/V.The produced biomass which started as 0.16% after 24h of fermentation increased and accumulated to 1.97g/l. An assessment of the produced alcohol showed that it had a boiling point of 78.830C,a specific gravity of 0.791g/cm3 and a pH of 3.53.The total alcohol yield was 11.86%V/V.The result of the experiment shows that sweet potato is a potential substrate for alcohol production  and biomass  used as single cell proteins.

Table of Contents Page

Title i

Certification ii

Dedication iii

Acknowledgement iv

Table of Contents v

List of Tables vii

Figures of Tables viii

Abstract ix

CHAPTER ONE

1.0 Introduction 1

1.2 Aim 4

1.3      Objectives 4

CHAPTER TWO

2.0 LITERATURE REVIEW

2.1 Sweet Potato 5

2.2 Nutritional Value 6

2.3 Saccharomyces cervisiae (Palm wine yeast) 7

2.4 History of Yeasts 8

2.5 Growth and Nutrition of Yeast 9

2.6 Nutritional Supplements 9

2.7 Alcohol Tolerance 10

2.8 Biomass 11

2.9 Fermentation 11

CHAPTER THREE 

3.0 MATERIALS & METHODS

3.1 Sources of Materials 13

3.2 Sweet Potato Processing 13

3.3 Sampling and Sample Preparation 13

3.4 Media Preparation 13

3.5 Isolation of palm wine yeast 14

3.6 Hydrolysis of Sweet Potato with Trichodermaviride (Saccharification) 15

3.7 Determination of pH 15

3.8 Determination of Titratable Acidity 16

3.9 Determination of Specific Gravity 16

3.10 Determination of Sugar 17

3.11 Determination of Biomass 18

3.12 Alcohol Distillation 19

CHAPTER FOUR

4.0 RESULTS

CHAPTER FIVE

5.0 DISCUSSION, CONCLUSION AND RECOMMENDATION

5.1 Discussion 26

5.2 Conclusion 27

5.3 Recommendation 28

References