Saccharification Of Soursop Peel For Ethanol Production

ABSTRACT

This work critically analyses the saccharification of soursop peel for ethanol production. The increasing demand for ethanol production for various industrial purposes has necessitated increased production of this ethanol using lignocellulose biomass. Lignocellulose biomass is very rich and abundant source of energy and in the process of reducing the cost of ethanol production, lignocellulose biomass is now of interest due to its abundant availability. Aspergillus niger with its high enzymatic activity was used to hydrolyse the pretreated soursop peels. After hydrolysis, Saccharomyces cerevisiae were inoculated into the hydrolysates separately at room temperature to ferment for 11 days. During fermentation period, changes in the quality parameters of pH, temperature, titrateable acidity, total solid, specific gravity, sugar contents and alcohol yield were monitored. The temperature fluctuated between 290C and 300C with pH decreasing from 6.20 to 2.40. The sugar content reduced from 21.01% to 2.23% alcohol contents increased to a maximum of 9.86%. The work reveals that soursop peel is a good substrate for bioethanol production regarding to its 9.86% yield of ethanol after saccharification.     

TABLE OF CONTENTS

Certification ﾿ i

Dedication ﾿ ii

Acknowledgment ﾿ iii

Table of Contents ﾿ iv

List of tables ﾿ viii

Abstract ﾿ ix

CHAPTER ONE

1.0 ﾿ INTRODUCTION ﾿ 1

1.1 ﾿ Saccharomyces cerevisiae ﾿ 6

1.2 ﾿ Aims ﾿ 7

1.3 ﾿ Objective ﾿ 7

CHAPTER TWO

2.0 ﾿ LITERATURE REVIEW ﾿ 8

2.1 ﾿ Soursop ﾿ 8

2.2 ﾿ Nutrient Composition of Soursop ﾿            12

2.2.1 ﾿ Lignocellulosic Biomass ﾿ 14

2.2.2 ﾿ Second Generation Feedstock ﾿ 14

2.2.4 ﾿ Hydrolysis and Fermentation Of Lignocellulosic Biomass ﾿ 15

2.3 ﾿ Bioethanol ﾿ 16

2.3.1 ﾿ Production and Utilization of Ethanol in Nigeria ﾿ 18

2.4 ﾿ Microorganisms of Interest in this Research Work ﾿ 20

2.4.1 ﾿ Aspergillus niger ﾿ 19

2.4.2 Saccharomyces cerevisiae                                                                                       20

CHAPTER THREE

MATERIALS AND METHODS

3.1 ﾿ Study Area ﾿ 21

3.2  ﾿ Source of Materials ﾿ 21

3.3 ﾿ Micro-Organisms ﾿ 21

3.3.1 ﾿ Sample Preparation (pre-treatment) ﾿ 21

3.3.2 ﾿ Preparation of Fungi Inoculums Aspergillus niger. ﾿ 23

3.4 ﾿ Preparation of Yeast Inoculums (Palm wine Yeast) ﾿ 22

3.5 ﾿ Media Preparation ﾿ 22

3.6 ﾿ Deliquification of substrate ﾿ 23

3.7 ﾿ Optimization of Hydrolysate ﾿ 23

3.8 ﾿ Saccharification for bioconversion to produce ethanol ﾿ 24

3.9 ﾿ Method of Analysis ﾿ 24

3..9.1 ﾿ Determination of pH ﾿ 24

3.9.2 ﾿ Determination of Temperature ﾿ 25

3.9.3 ﾿ Determination of Specific Gravity. ﾿ 25

3.9.4 ﾿ Determination of Total Solids ﾿ 26

3.9.5 ﾿ Determination of Titratable Acidity (TTA) ﾿ 26

3.9.6 ﾿ Determination of Sugar Content. ﾿ 27

3.9.7 ﾿ Determination of Ethanol Content ﾿ 28

3.9.8 ﾿ Statistical Analysis ﾿ 28

CHAPTER FOUR

4.1 ﾿ RESULT ﾿ 29

CHAPTER FIVE

DISCUSSION, CONCLUSION AND RECOMMENDATION ﾿

5.1 ﾿ Discussion ﾿ 31

5.2 ﾿ Conclusion ﾿ 32

5.3 ﾿ Recommendation ﾿ 32

﾿ Reference ﾿ 33

﾿ Appendices  ﾿ 40