EFFECT OF PROCESSING METHODS ON THE PROTEIN AND CYANIDE CONTENT OF AFRICAN YAM BEAN
ABSTRACT
Raw African Yam bean (Sphenostylis stenocarpa) was subjected to various processing methods Viz: steeping in water for 6 hr and then boiling for 10, 20, 30, minutes respectively (samples B); steeping in water for 12 hours and then boiling for 10, 20, 30, minutes respectively (sample C) and finally sample A was raw yam bean which served as control. The entire sample was dry – milled into fine flours. The glycosidic cyanide, crude protein, ash, moisture, some functional properties and bulk density of the flours were analyzed from the results, protein and cyanide content of sample A (raw sample) are 25.20% and 72.23ml. results showed that the toasting, process gave the highest protein (24.12) with no trace of cyanide and it negatively affected the protein content of the samples reducing it from 25.20 to 17.57, 17.51(%) respectively. 12 hours soaking and few minutes boiling process negatively affected the protein content of the samples reducing it from 25.20% to 13.12, 12.78, 12.09 (%) respectively but have the strongest impact in covering the cyanide level from 72.23ml to zero respectively. Moisture content ranges from 400% – 14%, Ash ranges from 2.50% to 5.00%, water absorption ranges from 105g/ml to 290g/ml, oil absorption ranges form 0.98 – 1.95g/m. The bulk density showed 0.74g/ml – 0.88g/ml.
TABLE OF CONTENTS
CHAPTER ONE
Introduction
CHAPTER TWO
2.0 Literature Review
2.1 Legumes
2.2 Nutritive Value Of Legumes
2.3 African Yam Bean
2.4 Utilization Of African Yam Bean
2.5.0 Limitations In The Utilization Of African Yam Bean
2.5.1 Unacceptable Flavour
2.5.2 Hard – To – Cook Phenomenon
2.5.3 The Presence Of Anti – Nutritional Factors
2.4.1 Pre – Conditioning Treatment Used In African Yam Bean Processing
2.7.0 Functionality of Legume Protein/Flour
2.7.1 Nitrogen Solubility
2.7.2 Water And Oil Absorption
2.7.3 Emulsion Capacity
2.7.4 Foam Capacity
2.7.5 Gelation
CHAPTER THREE
3.0 Materials And Source
3.1 Sample Preparation
3.2 Flow Charts For The Production Of The Different flour samples
3.2.1 Flow Chart For The Production Of Sample A (Raw Sample)
3.2.2 Flow Chart For The Production Of Samples B
3.2.3 Flow Chart For The Production Of Samples C
3.2.4 Flow Chart For The Production Of Toasted Sample (D Sample)
3.3.0 Determination Of Functional Properties Of African Yambean Flour
3.3.1 Water Absorption Capacity
3.3.2 Oil Absorption Capacity
3.4.0 Chemical Composition Of African Yam Bean
3.4.1 Determination Of Moisture Content
3.4.2 Determination Of Ash Content
3.4.3 Determination Of Crude Protein Content
3.5 Determination Of Glycosidic Cyanide
3.6 Determination Of Bulk Density
CHAPTER FOUR
Results / Discussion
CHAPTER FIVE
Conclusion and recommendation
References
