ABSTRACT
Proximate, mineral and vitamin analysis were carried out on three land snails (white skinned, black skinned and limicolaria species) for nutritional assessment using their muscular foot tissues. The mean of moisture ranged from 8.50 ± 0.10% in limicolaria to 10.40 ± 0.05% in white skinned. Crude fibre was not detected in any of the species. Crude fat of 1.23 ± 0.25 in limicolaria to 2.82 ± 0.25% in white skinned were obtained. Ash content Values as low as 1.50±0.50 in limicolaria to 2.50 ± 2.25% in white skinned were obtained. Crude protein ranged from 7.41± 0.02 in white skinned to 8.37 ± 0.02% in black skinned which had the highest value. Carbohydrate ranged from 60.40 ± 2.26% to 67.20 ± 0.67%. Mineral analysis of the snail species revealed relatively high amount of minerals in the white skinned compared to the black skinned and limicolaria species. Calcium values of 4.44 ± 0.02 in limicolaria spp to 6.77 ± 0.02mg /100g in White skinned were obtained. Magnesium ranged from 22.77± 0.01 in limicolaria to 26.44± 0.04 mg/100g in black skinned and Iron content ranged from 1.97 ± 0.01 in limicolaria to 2.44 ± 0.01mg/ 100g in white skinned with low potassium content of 79.50±0.05 in limicolaria species to 97.88 ± 0.02mg/100g in white skinned. Zinc ranged from 4.66 ± 0.01 in Black skinned to 5.66 ± 0.02 in white skinned.
Vitamin profile in white skinned were 6.25 ± 0.006%, 0.66 ± 0.006%, 0.025 ± 0.001% and 0.048 ± 0.001% for vitamin A, E, K and D respectively. While the black skinned was 8.37 ± 0.006%, 0.55 ± 0.006%, 0.035 ± 0.001% and 0.035 ± 0.001% for vitamin A, E, K and D respectively. The limicolaria ranged from 7.45 ± 0.006%, 0.49 ± 0.006%, 0.038 ± 0.001% and 0.037 ± 0,001%. This results therefore, encourages increase in production and consumption of snail species hence snail could complement the required trace minor elements needed for proper growth and development in human.
TABLE OF CONTENTS
TITLE PAGE – – – – – – – – i
CERTIFICATION – – – – – – – – – ii
DEDICATION – – – – – – – – – iii
ACKNOWLEDGMENTS – – – – – – – iv
ABSTRACT – – – – – – – – – vi
TABLE OF CONTENTS – – – – – – – – vii
LIST TABLES – – – – – – – – – ix
LIST OF FIGURES – – – – – – – – x
CHAPTER ONE: INTRODUCTION
1.1 Background of study – – – – – – – – 1
1.2 Justification of the study – – – – – – – 5
1.3 Aim of study – – – – – – – – – 5
1.4 Objective of study – – – – – – – 5
CHAPTER TWO: LITERATURE REVIEW
2.1 Land snail – – – – – – – – – 6
2.2 Nutritional value of snail meat – – – – – – 8
2.3 Uses of snail meat – – – – – – – – 12
2.4 Economic importance of land snail – – – – – 14
2.5 White skinned and black skinned (Archachatina marginata) – – 16
2.5.1 Limicolaria snail – – – – – – – – 21
2.6 Features of land snails – – – – – – – 23
2.7 Factors affecting snail meat – – – – – – – 25
2.8 Growth of snails – – – – – – – – 26
2.9 Food and feeding pattern of snails – – – – – – 27
2.10 Disease – – – – – – – – – – 28
2.11 Climatic conditions and soil characteristics – – – – 29
2.12 The Nature of snail nutrition – – – – – – 30
2.13 Health benefit of snail – – – – – – – 32
CHAPTER THREE: MATERIALS AND METHODS
3.1 Collection of samples – – – – – – – 34
3.2 Preparation of samples – – – – – – – 34
3.3 Proximate Analysis Procedure – – – – – – 38
3.3.1 Moisture determination using oven method procedure – – 38
3.3.2 Determination of ash content – – – – – – 38
3.3.3 Determination crude fibre – – – – – – – 39
3.3.4 Determination of fat – – – – – – – 40
3.3.5 Determination of protein – – – – – – – 40
3.3.6 Determination of carbohydrates – – – – – – 41
3.4 Mineral content determination – – – – – – 41
3.5 Vitamin determination – – – – – – – – – 42
3.5.1 Vitamin A and E assays – – – – – – – 42
3.5. 2 Vitamin K assays – – – – – – – – 42
3.5.3 Vitamin D assays – – – – – – – – 42
3.6 Data analysis – – – – – – – – – 42
CHAPTER FOUR: RESULTS AND DISCUSSION
4.1 Proximate composition of different breeds of land snail – – 44
4.2 Mineral composition of the land snail species – – – 47
4.3 Vitamin profiles – – – – – – – – 40
CHAPTER FIVE: CONCLUSION AND RECOMMENDATION
5.1 Conclusion – – – – – – – – – 50
5.2 Recommendation – – – – – – – – 50
REFERENCES – – – – – – – – – 51
APPENDIX – – – – – – – – – 55
CHAPTER ONE
INTRODUCTION
1.1 Background of study
The nutrients needed for life, growth and repair of body tissues are carbohydrates, protein, fats, minerals, water and fibre. The nutrient known to be usually in short supply is protein. Protein is of two origins: those from plants and those from animals. The FAO (Food and Agricultural Organization) in Nweze (2007) recommended 65-70g of protein per day per adult, out of which 35g must be of animal origin. The animal protein intake of many people is generally low leading to an acute malnutrition especially in developing countries. Oyenuga Amusan and Omidiji (1998) stated that the essential amino acids in animal protein are more balanced and readily available to meet human dietary requirements than those of plant origin. In support of this, Akinnusi, Oso, Afolabi, Sogunle and Bamgbose (2007) stated that animal proteins are known to be preferable and better when compared with plant proteins based on their balanced amino acid profile.