ABSTRACT
This study investigated the extraction via different solvents and characterization of oils from microwave and sun dried red and yellow pulp pawpaw (Carica papaya) seeds obtained from Calabar, Cross River State, Nigeria. The results showed a higher yield (40-50.5%) for oils extracted from microwave dried seeds using n-Hexane to sun dried seeds (20-40.5%). The physicochemical properties of seed oil revealed; pH (5.27±0.06 – 6.45±0.001, P≤0.05), specific gravity (0.95±0.01 to 0.98±0.01, P≤0.05), melting point (45.54±0.45-47.53±0.450-47.53, P≤0.05), viscosity (721.333±33.03 – 1162.00± 301.46, P≥0.05), peroxide value (2.16±0.29 – 4.33±0.63, P≤0.05), Acid value (2.43±0.32 – 4.01±0.58, P≤0.05), iodine value (24.11±2.91 – 94.54±1.91, P≤0.05) with saponification value being highest for sample MUT-DCM (207.57±5.61). The mineral content varied and showed significant difference in zinc (0.05±0.00 – 0.16±0.00mg/100g), magnesium (0.18±0.00 – 0.41±0.00 mg/100g), phosphorus (0.18±0.00 – 28.53±0.06 mg/100g), potassium (4.76±0.00 – 7.23±0.91m/100) and calcium (24.55±0.00 – 44.33±0.00mg/100g) having the highest concentration in GUT-DCM. On the other hand, the vitamin content of the oil showed fat soluble vitamin with higher values reported for vitamin A (7.850±0.000 – 11.050±0.00 IU/g, P≤0.005), compared to vitamin E (0.350±0.000 – 0.640±0.000 IU/g, P≤0.005), vitamin K (0.005±0.00 – 0.015±0.001 IU/g) and vitamin D (0.024±0.001 – 0.044±0.001 IU/g). It can be deduced that both species of Carica papaya seed oils are rich source of nutrients with respect to minerals and fat soluble vitamins present, making it useful in the cosmetic and pharmaceutical industries.
TABLE OF CONTENT
Title page – – – – – – – – i
Certification – – – – – – – – ii
Dedication – – – – – – – – iii
Acknowledgments – – – – – – – – iv
Abstract – – – – – – – – – v
Table of contents – – – – – – – – vi
List tables – – – – – – – – – x
List of figures – – – – – – – – – xi
List of plates – – – – – – – – – xii
CHAPTER ONE: INTRODUCTION
1.1 Background to the Study – – – – – – 1
1.2 Statement of the Research Problem – – – – – 3
1.3 Justification of the Study – – – – – – 4
1.4 Scope of the Study – – – – – – – 4
1.5 Aims/Objectives of the Study – – – – – – 4
CHAPTER TWO: LITERATURE REVIEW
2.1 Pawpaw (Carica papaya) – – – – – – 5
2.2 Pawpaw (Carica papaya) Seed – – – – – 6
2.3 Adaptation – – – – – – – – 10
2.4 Diseases of pawpaw (Carica papaya) – – – – 10
2.5 The Medicinal Values of Carica papaya. – – – – 10
2.6 Allergies and Side Effect of Carica papaya – – – – 19
2.7 Uses of Carica papaya Seed Oil – – – – – 20
2.8 Extraction – – – – – – – – 21
2.9 Methods of oil Extraction – – – – – – 22
2.10 Solvent Extraction – – – – – – – 30
2.11 Pawpaw Oil Extraction – – – – – – 33
2.11.1 Factor affecting Rate of Leaching – – – – – 34
2.11.2 Factor Governing Choice of Solvent – – – – – 34
2.12 Characterization of Oils – – – – – – 35
CHAPTER THREE: MATERIALS AND METHODS
3.1 Experimental Method – – – – – – – 37
3.2 Study Area – – – – – – – – 37
3.3 Preparation of seeds – – – – – – – 38
3.4 Extraction – – – – – – – – 38
3.6 Physicochemical Properties of Oil – – – – – 40
3.6.1 Determination of physical properties – – – – 40
3.6.1.1 pH – – – – – – – – – 40
3.6.1.2 Viscosity measurements – – – – – – 40
3.6.1.3 Specific Gravity – – – – – – – 40
3.6.1.4 Melting Point – – – – – – – 41
3.6.1.5 Yield – – – – – – – – – 41
3.6.2 Determination of Chemical Properties – – – – 41
3.6.2.1 Determination of Acid Value – – – – – 41
3.6.2.2Saponification Value – – – – – – – 42
3.6.2.3 Peroxide Value – – – – – – – 43
3.6.2.4 Iodine Value – – – – – – – – 43
3.7 Mineral content analysis – – – – – – 44
3.8 Vitamin profile analysis – – – – – – 44
3.9 Sample description – – – – – – – 44
CHAPTER FOUR: RESULTS AND DISCUSSION
4.1 Yield of the oil extracted – – – – – – – 46
4.2 Physiochemical properties of oil – – – – – 47
4.3 Mineral content of the oil – – – – – – 52
4.4 Vitamin content of the oil – – – – – – 55
CHAPTER FIVE: CONCLUSION AND RECOMMENDATIONS
5.1 Conclusion – – – – – – – – 55
5.2 Recommendation – – – – – – – –
REFERENCES – – – – – – – – 56
APPENDIX – – – – – – – – 56
