Abstract

This research was aimed at designing an industrial process for the production of Ogi from the fermentation of maize, using a powdered substrate. This was achieved by reviewing the traditional process and introducing a revised process. The steps involved in the revised process included grinding, sieving, fermenting (under anaerobic conditions) and drying. Analysis of varying fermented samples to overall composition of substrate (2-10%), varying moisture content (83-152%), varying temperature (30-50℃) and time (4-84 hours); and their effect on the growth rate of the active microorganisms was carried out. Also, microbiology tests are carried out using the traditional process and the revised process and the observations recorded. A controlled environment is proven to be created by introducing anaerobic conditions to the process. The model is obtained from this analysis and the optimal values for the target acidity value of 2.9 is given. It is concluded from the results obtained that the revised process adopted in this research is suitable for industrial production of Ogi.

Table of Content

TABLE OF CONTENTS
CERTIFICATION 2
DEDICATION 3
ACKNOWLEDGEMENT 4
TABLE OF CONTENTS 5
LIST OF FIGURES 8
LIST OF TABLES 8
ABSTRACT 9
CHAPTER ONE: INTRODUCTION 10
1.1: BACKGROUND OF STUDY 10
1.2: PROBLEM STATEMENT 11
1.3: AIMS AND OBJECTIVE OF STUDY 12
1.3.1: AIM 12
1.3.2: OBJECTIVE 12
1.4: METHOD AND SCOPE 13
1.5: RELEVANCE OF RESEARCH TO THE SOCIETY 13
CHAPTER TWO: LITERATURE REVIEW 15
2.1: OVERVIEW OF MAIZE. 15
2.1.1: HISTORY OF MAIZE RESEARCH IN NIGERIA 15
2.1.2: NUTRITIONAL VALUE OF MAIZE: 16
2.2: REVIEW OF PASTWORKS ON OGI 18
2.2.1: FERMENTATION DYNAMICS DURING PRODUCTION OF OGI, A NIGERIAN FERMENTED CEREAL PORRIDGE by Omemu, A.M. 18
2.2.2: MICROORGANISM IN PRIMARY FERMENTATION OF MAIZE FOR OGI PRODUCTION by Okpalla, J. and Onyeneto, T.C. 19
2.2.3: ISOLATION OF ANTIMICROBIAL PRODUCING LACTOBACILLI FROM AKAMU (A NIGERIAN FERMENTED CEREAL GRUEL) 20
2.3: OVERVIEW OF PREDOMINANT BACTERIA SPECIES 21
2.3.1: LACTOBACILLUS SPP 21
2.3.2: CHARACTERISTICS OF LACTOBACILLUS PLANTARIUM 21
2.4: ISOLATION OF MICROORGANISMS 23
2.4.1: Nutrient Agar 23
2.4.2: MRS Agar 24
2.4.3: MacConkey Agar 25
2.4.4: Gram Staining 26
2.5: OVERVIEW OF FERMENTATION PROCESS 31
2.5.1: TRADITIONAL TECHNIQUE FOR FERMENTATION PROCESS 31
2.6: BIOREACTORS AND CELL GROWTH RATE LAWS 32
2.6.1: BIOREACTORS 32
2.6.2: CELL GROWTH 33
2.6.3: RATE LAWS 36
2.6.4: DOUBLING TIME 36
2.7: STUDY OF EXPERIMENTAL TECHNIQUE USED 37
2.7.1: FACTORIAL EXPERIMENTAL DESIGN 37
2.8: ECONOMIC ANALYSIS OF IMPACT OF INDUSTRIAL PROCESS OF OGI PRODUCTION IN NIGERIA. 38
CHAPTER THREE: METHODOLOGY 41
3.1 RAW MATERIALS AND REAGENTS 41
3.2 INSTRUMENTATION AND EQUIPMENT 41
3.3: METHODS AND EXPERIMENTS 42
3.3.1: ISOLATION OF BACTERIA PRESENT DURING TRADITIONAL METHOD FOR FERMENTATION. 42
3.3.2: DETERMINING THE BEST CONDITIONS TO ACHIEVE THE THRESHOLD PH FOR FERMENTATION PROCESS. 43
3.3.3: ISOLATION OF BACTERIA IN SELECT EXPERIMENT 2 RUNS 57
3.4: SAFETY PRECAUTIONS 58
CHAPTER FOUR: RESULTS AND DISCUSSION. 60
4.1: RESULTS 60
4.1.1: Experiment 1 Results 60
4.1.2: Experiment 2 Results 60
4.1.3: Experiment 3 Results 64
4.2: DISCUSSION OF RESULTS 65
4.2.1: Discussion of experiment 1 65
4.2.2: Discussion of experiment 2 65
4.2.3: Discussion of Experiment 3 66
CHAPTER FIVE: CONCLUSION AND RECOMMENDATION 68
5.1: CONCLUSION 68
5.2: RECOMMENDATIONS 68
REFERENCES 69
APPENDICES 71
APPENDIX A 71
APPENDIX B 81

Introduction

According to Sahlin, 1999, one tenth of the children under five years of age dies due to dehydration in most developing countries. The dehydration is mainly caused by so many severe cases of diarrhoea. The main reason for contacting diarrhoea is the ingestion of food that does not have the appropriate standard regarding the hygienic conditions. The hygienic standard of a food is based on the processing and handling of the food, as much as on the conditions of the raw materials. A food item prepared with water that is contaminated with pathogenic microorganisms, will successively become contaminated, and as such becomes a health risk.
It is known that pathogenic microorganisms normally found in food is not be able to grow in an acidic environment that is at pH below four. This acidity is characteristic of lactic acid fermented food. This is the case in the Fermentation of maize to get Ogi. (Sahlin, 1999)
Traditionally, Ogi, also known as Akamu or Pap, is produced generally by steeping corn grains in warm water for one to two or three days followed by wet milling and sieving through a screen mesh. The sieved material is allowed to sediment and fermented, and is marketed as wet cake. Various food dishes are made from the fermented cakes or Ogi. During the steeping period, S. cerevisiae, Enterobacter cloacae and Lactobacillus Plantarum have been found to be prominent in traditional ogi fermentation.

FIGURE 1.1: TRADITIONAL METHOD FOR PREPARING OGI

In Nigeria, Ogi is the most preferred for weaning infants and it is made from maize (zea mays), millet (Pennisetumamericanum), or guinea corn (Sorghum spacers). Using Anambra state as case study, it is found that most mothers introduce the thin gruel at three to six months of age. The baby is fed on demand with a spoon while some mothers use the traditional forced hand-feeding method. After the successful introduction the thin gruel, other staple foods in the family menu are introduced to the child. (Egwim, et al,. 2013)

Industrial process for the production of Ogi from the fermentation of maize using a powdered substrate

Key Features

Table of Content

Introduction