ABSTRACT

The effect of alkaline steep treatment on the gelatinization temperature and beta - amylase activity of malt from white sorghum grain was investigated. Germination was carried out for 4 days at 30°C after steeping in solution of Ca(OH)2, KOH, Ca(OH)2/KOH, as well as distilled water, respectively. Unmalted grains given the same treatment were also evaluated. Bulk density', swelling capacity, gelation capacity, gelatinisation temperature, beta - amylase activity and soluble carbohydrate of both the malted and unmalted samples were determined. Bulk density and swelling capacity were found to be affected by period of malting. Gelation capacity on the other hand was affected by treatment given. The treatment and period of malting had no effect on the soluble carbohydrate content and gelatinization temperature of the grain. amylase activity was found to be enhanced by alkaline treatment and by period of malting. The best result was obtained with sample malted for 2 days and treated with KOH. The sample tie.ited with KOH and malted for 2 days was used to brew beer without addition of exogenous enzyme. Also sample treated with Ca(OH)2as well as unmalted sorghum treated with exogenous enzymes used to brew was used to brew beer and the organoleptic properties of these drinks were determined in comparison with a control (Golden Guinea Beer).

TABLE OF CONTENTS

TITLE PAGE ii

CERTIFICATION iii

•ABSTRACT iv

DEDICATION vi

ACKNOWLEDGEMENT vii

TABLE OF CONTENT ix

CHAPTER ONE

Introduction

Malting

Mashing

Fermentation

CHAPTER TWO

Literature Review 6

Origin of Sorghum Grain 6

Nutritional Composition of Sorghum Grain 8

Uses of the Sorghum Grain 1•1

Traditional uses 1 2

Industrial Uses 1 2

Enzymology of Sorghum Malt 13

Problems Associated with use of Sorghum in Brewing 14

Malting - Problems encountered 1 5

Mashing Problems encountered 1 6

Starch Gelatinization 16

Beta-Amylase activity 17

CHAPTER THREE

Materials and Methods 21

Sorghum Matting 21

Bulk Density 22

Determination of Gelation capacity 23

Determination of Swelling capacity 23

Determination of Gelation Temperature 23

3-Amylase Activity 24

Determination of Soluble Carbohydrate 25

Brewing of Sorghum Beer 26

Sensory Evaluation of Beer 27

CHAPTER FOUR

Result and Discussion 28

CHAPTER FIVE

Conclusion and Recommendation 35

References 36

Appendix I 40

Appendix II 40

Appendix III 43

Appendix IV 49