ABSTRACT

With a carbohydrate level of 72.19%, breadfruit has the potentials for  use as a source of ethanol to complement the search for alternative barley replacement. Earlier researchers on the use of breadfruit as source of ethanol for the brewery sector were met with scime problems such as rancidity and off-flavour development. Malting of breadfruit at 28 ± 1°c for 10 days yielded a 96% Germination capacity and total malting loss of 25.7%. However grain dormancy was broken by the 2nd day. Part of the ground malted flour was defatted to a final fat content of 0.78%. Fullfat breadfruit and defatted breadfruit grits which were used as adjuncts in a ratio 3:5 (adjunct: barley) yield wort samples whose parameters (extract, ethanol, pH, specific gravity, sugar) were measured over a period of 9 fermenting days after yeast inoculation. Values of the parameters obtained are compared with that obtained from wort with maize as adjunct. Analysis of values revealed significant difference between wort samples in extract yield of 12.59%, 9.66% and 11.23% and ethanol production of 5.79, 6.39 and 6.10 for fuilfat, defatted and maize wort samples respectively. The trend of fermentation equally illustrated the existence of more fermentable sugar in breadfruit than in maize. Defattening of breadfruit eliminated the difficulties experienced by earlier researchers hence paving way for efficient utilization of high fermentable sugar, already in existence, by yeast for the production of ethanol.

TABLE OF CONTENTS

Title page

Certification

Dedication

Acknowledgement ii

Table of Contents ui-v

List of tables vi

List of figures vi

Abstract vii

1.0 Chapterone 1

1.1 Introduction 1

1.2 Statement of Research problem 2

1 .3 Research objectives 2-3

1.4 Justification 3

CHAPTER TWO

2.0 Literature Review 4

2.1.0 Cereals 4-8

2.1 .1 Contributions of creaIs 8-9

2.1 .2 Industrial utilization of cereals 9-1 1

2.2.0 Adjuncts/alternatives/replacement to barley 12-14

2.3.0 Yeast 14-16

2.31 Yeast growth factors 17

2.4.0 Fermentation 17-19

2.5.0Malting 19-21

2.5.1 Steeping 21-23

2.5.2 Dormancy and viability 23-24

2.5.3 Germination 24-25

2.5.4 Kilning 25-26

2.5.5 Malting losses 26-27

2.5.6 Malting additives 27-29

2.5.7 Biochemistry of malting 29-30

2.5.8 By — products of malting 30-3 1

2.5.9 Malting analyses 31

Chapter Three

3.0 Materials and methods 32

3.1 Sourceofrawmaterial 32

3.2 Proximate analysis 32

3.2.1 Moisture content determination 32-33

3.2.2 Crude protein determination 33

3.2.3 Ash content determinatioi; 33

3.2.4 Fat determination 34

3.2.5 Crude fibra determination 34

3.2.6 Carbohydrate determination 35

3.3.0 Sample preparation 35

3.3.1 Malting 35

3.3.2 Defattening 35

3.3.3 Yeast preparation 35

3.3.4 Mashing 36-37

3.4.0 Analysis of fermenting wart 37

3.4.1 Specific gravity determination 37

3.4.2 pH determination 37

3.4.3 Ethanol content determination 37

3.4.4 Titratable acidity 37

3.4.5 Germination capacity determination 38

3.4.6 Malting loss determination 38

CHAPTER FOUR

4.0 Result and discussion 39

4.1 Proximate analysis 39-40

4.2 Malting characteristics 40-41

4.3 Fermentation parameters 42-44

CHAPTER FIVE

5.0 Conclusion and Recommendation 45

Reference

Appendixes