Thesis Abstract

Abstract
Afzelia africana (Akpalata) and Brachystegia spp are commonly consumed in West Africa for their nutritional benefits. This study aimed to investigate the effect of processing on the properties of flour obtained from these plant species for use as soup thickeners. The raw materials were collected, cleaned, and processed into flour using different methods including sun drying, oven drying, and milling. The flours obtained were analyzed for their proximate composition, particle size distribution, water absorption capacity, and viscosity. Results showed that processing methods significantly influenced the nutritional composition of the flours. Sun-dried flour had higher protein content compared to oven-dried flour for both Afzelia africana and Brachystegia spp. However, oven-dried flour had higher carbohydrate content. Both flours had similar fat content regardless of the processing method. Particle size distribution analysis revealed that milling significantly reduced the particle size of the flours, leading to a finer texture which could potentially improve their thickening properties. Water absorption capacity was found to be higher in sun-dried flour compared to oven-dried flour, indicating that sun drying may better preserve the hydration properties of the flours. Rheological studies showed that the viscosity of the flours varied depending on the processing method and concentration. Brachystegia spp flour exhibited higher viscosity compared to Afzelia africana flour, suggesting differences in their thickening capabilities. Overall, processing methods had a significant impact on the properties of Afzelia africana and Brachystegia spp flours as soup thickeners. Sun drying was found to be more favorable in preserving the protein content and water absorption capacity of the flours, while milling improved the particle size distribution and potentially enhanced thickening properties. Understanding the effects of processing on these traditional ingredients can provide valuable insights for optimizing their utilization in food applications, particularly as soup thickeners in West African cuisine.

Thesis Overview

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 product the most acceptable soup for the consumers?
3. To determine the proximate composition of Brachystegia spp (Achi) and Afzelia Africana (Akpalata).