ABSTRACT

Tiger nut (Cyperus esculentus) wine produced by fermentation of Tiger nut juice using locally isolated Saccharomyces cerevisae from palm wine and commercially purchased baker’s yeast were evaluated for their physico-chemical composition and quality. The juice extracted from the tigernut tubers were inoculated separately with the palmwine and baker’s yeast respectively. The results of the analysis revealed that tiger nut wine produced had a final 13.18% alcohol content, 0.87% total titrable acidity, a pH of 3.19 and 7.9% total sugar content after 7days of fermentation. The wine fermented with palmwine yeast had an initial TTA value of 0.42 which later rose to 0.87 after 7days of fermentation, while that fermented with the baker’s yeast had an initial 0.41 before increasing to 0.88 after 7 days of fermentation. It was observed that commercial-yeast  and  palmwine  strain  presented  higher  alcohol  yield  and  better efficiency in  converting the sugar tigernuts into  alcohol,  with  alcohol  yields  of 13.04% and 13.18% respectively after 7 days of fermentation. This study recommends that wine of tiger nut could be fermented at temperature range of 27oC to 37oC which is favourable to yeast growth. The production of wine from sources other than grapes could prove economical owing to the fact that tiger nut is a high-yielding, readily-available tuber which has lots of dietary and medicinal values.

TABLE OF CONTENTS

Title Page i

Certification iii

Dedication iv

Acknowledgement v

Table of Contents vi

List of Tables viii

List of figures ix

Abstract x

CHAPTER ONE

1.0 INTRODUCTION 1

1.1 Aim and Objectives 4

CHAPTER TWO

2.0 LITERATURE REVIEW 5

2.1 History of Tigernut Tubers 7

2.2 Tiger nut (Cyperus esculentus L.) 9

2.2.1 Nutritive value and Benefits of Tigernut Tubers 10

2.2.2 Tiger Nut Milk 11

2.2.3 Microbiology 15

2.3 Nutritional Importance of Tiger nut 16

2.4 Tiger Nut Oil 18

2.5 Economical and Nutritional benefits of Tiger nut 19

2.6 Microbiology of Tiger nuts Spoilage 21

2.7 Wine Fermentation 22

2.8 Yeasts 22

CHAPTER THREE

3.0 MATERIALS AND METHODS 25

3.1 Materials 25

3.2 Preparation of Tigernut Milk 25

3.2 Isolation of yeast from palmwine 25

3.3 Preparation of Inoculum Starter Culture 26

3.3.1 Microbial Analysis 26

3.4 Physico-Chemical Analysis 27

3.4.1 Total Titrable Acidity 27

3.4.2 Total Sugar Content 27

3.4.3 pH and Temperature 28

3.4.4 Alcohol Content 28

3.5 Determination of Biomass Concentration 28

CHAPTER FOUR

4.0 RESULTS 29

CHAPTER FIVE

5.0 DISCUSSION 36

5.2 Conclusion 39

References