THE EFFECT OF PROCESSING ON AFZELIA AFRICANA (AKPALATA) AND BRACHYSTEGIA SPP FLOUR AS SOUP THICKENER

ABSTRACT

The effect of different processing methods on the functional properties of Akpalata (Afzelia Africana) and Achi (Brachystegia spp) flours were investigated. Parameters studied included the proximate composition, functional properties and sensory evaluation. Results of the proximate showed that (1% moisture 13, fat 13.83%, Ash 5.3%, crude protein 17.76% crude fibre 2.8%, carbohydrate 47.78%)while functional properties results showed that (Emulsification Capacity 2.7%, Water absorption 428% Oil absorption 14%, Gelatinization temperature 67oc) and organoleptic properties showed that boiling acid (Sample D) gave the best qualities required. The results of organoleptic properties showed that colour 6.58. texture 6.86, taste 6.83, general acceptability 6.82. toasting or roasting was found to be a good processing method for Akpalata (Afzelia africana). Sample D and B had good gelling property attributed to good soup Thickening. They also have good oil absorption capacity, which improves mouth feel which were generally acceptable

TABLE OF CONTENTS

Title Page
Abstract
Table of Contents
CHAPTER ONE
1.0 Introduction
1.1 Aims and Objective of the Work
1.2 Objective of the Study CHAPTER TWO
2.0 Literature Review
2.1 Akpalata (Afzelia africana)
2.3 Processing and Utilization of Afzelia africana (Akpalata)
2.4 Achi (Brachystegia spp)
2.5.0 Processing and Utilization of Achi (Brachystegia spp)
2.5.1 Rheological Properties
2.5.2 Types of Fluid Flow
2.5.3 Newtonian Flow
2.6.0 Pseudoplastic and Dilatant Fluid Flow
2.6.1 Bingham Flow
2.6.2 Flow Characteristics of Fluid Foods
2.6.3 Functional Properties Evaluation
2.6.4 Gelation
2.6.5 Emulsification
2.6.6 Water Absorption
CHAPTER THREE
3.0 Experimental Method and Materials
3.1 Raw Material and Instruments Used
3.2.0 Sample Preparation
3.2.1 Processing of (Afezlia africana) flour
3.2.2 Processing of Achi (Brachystegia spp) flour
3.3 Proximate Analysis
3.3.1 Determination of Moisture Content
3.3.2 Crude Fat Content Determination
3.3.3 Crude Fibre Determination
3.3.4 Carbohydrate Content
3.3.5 Functional Properties Determination
3.3.6 Oil Absorption
3.4 Water Absorption
3.4.1 Gelation Temperature
3.4.2 Emulsification Capacity
3.4.3 Organoleptic / Sensory Evaluation
3.4.4 Soup preparation
3.5 Sensory Evaluation
3.5.1 Statistical Analysis
3.5.2 Sensory Evaluation
3.5.3 Statistical analysis
CHAPTER FOUR
4.0 Results and Discussions
4.1 Functional Properties
4.1.2 Water Absorption
4.1.3 Oil Absorption
4.1.4 Emulsification Capacity
4.1.5 Gelatinization Temperature
4.2 Sensory Evaluation
4.2.1 Colour / Appearance
4.2.2 Texture
4.2.3 Taste
4.2.4 General Acceptability
CHAPTER FIVE
5.1 Conclusion
Recommendation
References
Appendices

LIST OF TABLES

TABLES

1. Flow Characteristics Of Fluid Foods
2. Proximate Composition of Akpalata (Afzelia Africana) Flour and Achi (Brachystegia spp) Flour
3. Functional Properties
4. Effect of Processing on the Set Back Values
5. Summary of Sensory Evaluation Results
6. Emulsification Capacity
7. Anova Emulsification Capacity of Samples
8. Anova Gelatinization Temperature for Samples
9. Anova Set Back Value
10. Anova of General Acceptability

CHAPTER ONE

1.0 INTRODUCTION

Nigeria is presently passing through a developmental stage in which there is showing emphasis on local sourcing of raw materials and so there is a growing commercial interest in processing Nigerian foods.
The mechanism by which culinary products are thickened to varying degrees can be subdivided into three separate processing such as starch thickening, protein coagulation and emulsification.

The role of the skilled cook when preparing starch achieve an overall product quality in terms of texture, consistency, appearance, flavour and yield.

The techniques used are many and varied which many include adequate dispersal of raw starch flour in the soup.

The processes ensure that each starch granules is free to take part in the thickening gelatinization process, hence, using correct recipe balance method and thorough stirring or agitation at all stages of preparation of cooking to prevent starch clumpiness and lumpiness.

Richard Maryland, Derek Welsby (1979)

The seeds of Afzelia Africana (Akpalata) and (Brachystegia spp) (Achi) undergo various mechanical devices like cracking the seed before boiling in water followed by dehulling and grinding into flour in large quantities before it can be preserved for future consumption.

If this is achieved it helps to reduce the seasonal glut of the product and scarcity of the local thickening agents experienced each year.

Functional properties are influenced by the method of processing. Those processing methods are influenced by the functional, rheological and cooking qualities of the soup (Anazonwu, 1976).

Information are required to guide the food processor to choose the processing method that will give the most acceptable product.

Commercial production of tradition thickening agent will help the food engineer in the design choice of appropriate handling equipment and food processing system to be adopted.

The constraint encountered in the use of many thickening agents in soup-making is generally there composition of some anti-nutritional factors which nay induced flatulence and other digestive disorder arising from their consumption.

1.1 PROBLEM OF THE STUDY

People have been dealing on these edible indigenous woody plants (Akpalata and Achi) without knowing the food values, how to process, grow and preserve them.

Meanwhile, the general causes of all these negligent.

1. Are due to dealing much on imported thickening agent and as a result overlook the locally made ones.
2. Lack of encouragement and lack of skills on how to prepare them.
3. Non-availability of these traditional thickening agents all the year round.
4. People having little or no knowledge of some of soup thickeners.

Therefore, in order to solve the above problems, it will be very important to identify, classify and to find out utilization of these plants or seeds.

Again, to inculcate the knowledge into people in order to eliminate those factor like negative attitude, ignorance or non-availability of these thickeners all the year round.

1.2 OBJECTIVE OF THE STUDY

1. To compare the effect of processing on the thickening qualities of (Brachystegia spp) and Afzelia Africana.

2. To determine the method of processing which will produce the most acceptable soup for the consumers?

3. To determine the proximate composition of Brachystegia spp (Achi) and Afzelia Africana (Akpalata).