EFFECT OF PRE-PROCESSING OPERATIONS, ANTI-NUTRITIONAL COMPOSITION OF AFRICAN PEAR SEED (DACRYODES EDULIS)

ABSTRACT

African pear (Dacryodes edulis) fruit were sorted, cleaned and divided into three equal Parts. A portion was processed raw while the others were subjected to preheat treatment (roasting in hot ash and blanched in hot water) to soften the pulp. They were all de pulped, dehulled, and sun dried. The cotyledons were milled, sieved through a 2-mm aperture size sieve and packaged for analysis. The proximate analysis and anti-nutrient of the meal were done using an approved methods the result were statistically analyzed using one-way analysis of variance (ANOVA), the means separated using Duncan’s multiple Range test. From the results the preheat treatment slightly reduced the anti Nutritional composition though their levels were low even in the raw samples with the exception of falconoid that the contents ranged from (30.78-34-34.07) mag/100g. the other anti-nutrients such as tannins, phytate and oxalates ranged (0.04-0.05) mg/100g, (0.30-0.50) mg/100g and (0.02-0.04)mg/100g respectively. The ash and crude fibre content increased slightly with pre-heating while moisture, fat, protein and carbohydrates reduced with pre-heat treatment. High temperature and prolonged heat treatment and other pre-processing operations should be applied in the African pear seeds process in other to make them toxic free and safe for human consumption.

TABLE OF CONTENTS

Title page…………………………………………………………………………………i
Certification ……………………………………………………………………………ii
Dedication………………………………………………………………………………iii
Acknowledgement………………………………………………………………….iv
Abstract…………………………………………………………………………………..v
Tables of content……………………………………………………………………vi
CHAPTER ONE
1.1 Introduction………………………………………………………………..1-5

CHAPTER TWO
2.0 Literature review……………………………………………………………6
2.1 African pear ………………………………………………………………6-7
2.2 Nutritional composition of African pear………………………7
2.3 Uses of African pear…………………………………………………8-10
2.4 Anti-nutritional factors in plants used for human food and animal feeds……………………………………………………10-12
2.5 Classes of anti-nutritional factors…………………………12-15
6 Methods for quantification of anti-nutrients………….15-16
2.7 Effect of processing on anti-nutrients in legumes/seeds………………………………………………………16-18

CHAPTER THREE
3.0 Materials and methods…………………………………………………19
3.1 Raw material collection and samples preparation..19-20
3.2 Analysis of samples……………………………………………………..21
3.2.1 Anti-nutriutional content determinate………………..21
3.2.1.1 Determination of tannin content…………………………21
3.2.1.2 Determination of phytic acid:………………………21-22

3.2.1.3. Oxaliate precipitation……………………………………22-23
3.2.1.4 Flavonoid determination:……………………………………23
3.2.2 Proximate composition analysis………………………….24
3.2.2.2. Ash content determination………………………………….25
3.2.2.3 Crude protein determination…………………………25-26
3.2.24. Fat content determination…………………………………26
3.2.2.5 Crude fibre determination……………………………27-28
3.2.2.6 Carbohydrate content determination…………………29
3.3 Statistical analysis…………………………………………29-30
CHAPTER FOUR
4.0 Results and Discussion…………………………………………31-35

CHAPTER FIVE
5.0 Conclusion/Recommendation………………………………………35
References………………………………………………………………………36-38