ABSTRACT
The study
examined the nutrient composition of shade and sun-dried fluted pumpkin leaf
and the curd produced from the leaf. The effects of the processed leaves and
the curd on beta carotene, iron, ascorbate, zinc, copper and calcium status of
rats were evaluated. Fluted pumpkin leaf was divided into four (4) portions. One
was shade-dried, another was sun-dried and the other was used to produce leaf
curd. The last portion was not processed and served as the control. All the
processed samples were milled to fine flour and analysed using standard
methods. Each of the pumpkin leaf flour was incorporated into rat chow to
provide 2.1 mg beta carotene daily for a 28-day study period. Twenty (20) male
weanling rats were divided into four (4) groups of five (5) rats each. They
were housed in individual metabolism cages and fed diets and water ad libitum. Blood samples were drawn
before and after the experiment by ocular puncture and were used for
biochemical analysis. Blood plasma was used to determine haemoglobin while
serum was used to determine pro- vitamin A, ascorbate, ferritin, iron, copper,
zinc and calcium. The liver was individually removed and analysed for liver
ferritin, ascorbate and other micronutrients. The results showed that sun-dried
fluted pumpkin leaf had comparable (p>0.05) protein value (23.78%, 23.08%,
19.75%) with the shade-dried and dried leaf curd. The fresh pumpkin leaves had
higher (83.57μg) (p<0.05) pro-vitamin A than all processed samples (41.09μg,
14.56μg, 0.88μg). The iron, copper, zinc and calcium levels of the sun-dried
and dried leaf curd sample were similar (p>0.05). The rats fed rat chow
supplemented with dried leaf curd had higher serum beta carotene, ascorbate,
and ferritin than those of the other groups. The rats fed rat chow supplemented
with shade dried-fluted pumpkin leaf had higher (p<0.05) haemoglobin level,
liver beta-carotene and ascorbate than the other groups. The result showed that
processing fluted pumpkin leaf into leaf curd improved serum beta-carotene,
serum and liver ascorbate, serum ferritin and liver iron of rats more than
other processing methods.
TABLE OF CONTENTS
Title page … … … … … … … … … … i
Acknowledgment … … … … … … … … ii
Dedication… .. … … … … … … … … iii
Table of content… … … … … … … … … iv
Abstract … … … … … .. .. … … v
CHAPTER ONE: INTRODUCTION
- Background of
the study… … …… … … .. … 1
- Problem statement … … …… … … … … 2
- Objectives of the study… … …… … … … … 4
- Significance of the study… … …… … … … … 4
CHAPTER TWO: LITERATURE REVIEW
2.1.1 Vegetables… … … .. … … … … … 5
2.1.2 Utilization … … … … … … … … 6
2.1.3 Nutrient composition … … … … … … … 7
2.1.4 Effect of processing on the nutrient content of green leaf vegetables … 11
2.2.1 Fluted pumpkin leaves… … … … … … … 14
2.2.2 Uses and nutrient composition… … … … … … 15
2.3 Leaf curd… … .. … … … … … … 18
2.4 Vitamin A and iron… … … … … … … … 19
2.4.2 Vitamin A and iron studies… … … … … … … 20
2.4.3 Biochemical studies… … .. .. … … … … 22
CHAPTER THREE: MATERIALS AND METHOD
3.1.1 Fluted pumpkin … … … … … … … 25
3.1.2 Preparation of sample … … … … … … 25
3.2 Chemical analysis … … … … … … … 25
3.2.1 Proximate analysis … … … … … … … 27
3.2.1.1 Crude protein … … … … … … … … 27
3.2.1.2 Total lipids … … … … … … … … 28
3.2.1.3 Total ash … … … … … … … … 28
3.2.1.4 Crude fibre … … … … … … … … 28
3.2.1.5 Carbohydrate … … .. … … … … … 29
3.2.1.6 Moisture … … … … … … … 29
3.2.2 Vitamin … … … … … … … 29
3.2.2.1 Pro- vitamin A … … … … … … … 29
3.2.2.2 Minerals –Iron, Copper, Zinc, d Calcium … … … … 31
3.2.2.3 Measurement of haemoglobin concentration …… … … … 33
3.3 Animal experiment … … … … … … 35
3.3.1 Diet formulation … … … … … … 35
3.3.2 Animal Housing and feeding . … .. … … … 35
3.3.3 Analysis of blood and liver samples … … … … … 35
3.3.3.2 Serum and liver ferritin concentration …… … … … 36
3.3.3.3 Measurement of serum and liver iron concentration … … … 36
3.3.3.4 Serum and liver B-carotene … … … …… … … 36
3.4 Statistical analysis … … … … … … 36
CHAPTER FOUR: RESULTS
4.1 Proximate composition of differently processed fluted pumpkin
(Telfaria occidentalis) leaves “as is”… … … … … … 37
4.2 Proximate composition of differently processed fluted pumpkin
(Telfaria occidentalis) leaves on dry matter basis … … 39
4.3 Vitamin and mineral composition of differently processed fluted
pumpkin (Telfaria occidentalis) leaves on dry matter basis … … 41
4.4a Mean serum beta-carotene, ascorbate and ferritin of rats before
and after feeding … … … … … … … … 43
4.4b Mean serum iron, zinc and copper of rats before
and after feeding … … … … … … … … 44
4.4cMean serum calcium and haemoglobin of rats before
and after feeding … … … … … … … … 45
4.5 Liver beta-carotene, ascorbate, ferritin, iron, copper, zinc and calcium
Levels of the rats … … … … … … … … 47
CHAPTER FIVE: DISCUSSION
5.1 Discussion … … … … … … … … 49
Conclusion … … … … … … … … 54
Recommendation … … … … … … … … 54
References … … … … … … … … 55
CHAPTER ONE
INTRODUCTION
BACKGROUND OF THE STUDY
A vast majority of individuals in the third world countries are not able to satisfy their nutritional requirements for growth and development. This leads to malnutrition, which is one of the major causes of death, particularly in infants and young children. Malnutrition can manifest as protein-energy malnutrition (PEM) and micronutrient deficiency. Micronutrients are involved in metabolism of energy nutrients and their deficiency may precipitate PEM as well as their specific deficiency diseases.
Despite the approaches on the past geared towards combating micronutrient deficiencies through supplementation in form of drugs, fortification of some food products and other measures, the problem still exists. This is because most people do not routinely take their supplements as they view it as drug and others abuse it as prescribed. Most of our fortified food products are costly and the poor in the rural communities and the low socio-economic groups cannot afford to purchase them. They depend on their cheaper and low micronutrient familiar unfortified products.
The World Health Organisation (WHO) has classified Nigeria among the 34 countries in the world with serious problems of nutritional blindness and xerophtalmia. Data from Participatory Information Collection (PIC) survey done in Nigeria showed that the prevalence of vitamin A deficiency (VAD) in 1993 was 9.2% in children and 7.2% in mothers (FGN/UNICEF, G-1994). Iron deficiency anaemia affects more than 3.5 billion people in the developing world (UNICEF/UNU/WHO/MI, 1999).
It has been noted that the prevalence of these micronutrients deficiencies are more in developing countries than in developed countries. WHO/OMS (2003) reported that VAD is a public health problem in 118 countries, especially in Africa and South-East Asia. Young children and pregnant women are vulnerable. The most affected groups in developing countries are pregnant women (56%), school-age children (53%), non-pregnant women (44.6%) and preschool children (42%) (ACC/SCN, 2000).
The problems associated with these micronutrient deficiencies are much and irreversible proceeding death. In children, it greatly increases the chances of morbidity and disability. Maternal night blindness was associated with almost four fold increase in the risk of mortality (Christian et al., 2000).
Based on the diverse effects of iron and vitamin A deficiencies, it is important that preventive measures capable of combating these deficiencies be adopted, especially diversification of diets at the reach of the low income groups.
- PROBLEM STATEMENT
The inherent problem of micronutrient deficiency is very difficult to combat because as hidden hunger, it is not easily detected. An estimated 250,000 to 500,000 vitamin A deficient children get blind every year (WHO/OMS, 2003). Half of them die within 12 months of loosing their sight. Nearly 600,000 women die from childbirth-related causes each year, the vast majority of them from complication which could be reduced through better nutrition, including provision of vitamin A. Vitamin A deficiency (VAD) is the leading causes of preventable blindness in children and raises the risk of diseases and death from severe infection. Lack of vitamin A in children causes severe visual impairment and significantly increases the risk of severe infections and death from such common childhood infections as diarrhoea disease and measles. It has been shown that iron deficiency and anaemia affect more people than any other condition constituting a public health problem. It is well documented that iron deficiency leads to impaired cognitive development and lower school achievement (Granthan – Mc Gregor and Ani, 2001; WHO/NHD/Verney and Nabarro, 2003).
As a result of these life threatening effects of both vitamin A and iron deficiencies, there is a need to adopt an intervention programme that would be within the reach of the low socio-economic groups who are mostly affected. Dietary diversification using locally available foods within the communities appears to be a more feasible approach in rural communities than other approaches. However, the problem with this approach is dietary bulk and bioavailability of nutrients, particularly in the complementary infant food. This is because the stomach capacity of infants is too small (200-250ml). They will consume little quantity of food at a time, which may not meet the recommended requirement for all the nutrients (WHO, 1998). It is necessary to reduce the bulk of infant foods so that the little quantity consumed would be concentrated to meet the nutrient requirements of the infant. This study would address the problem of dietary bulk in infants feeding by developing leaf curd from fluted pumpkin (Telfaria occidentalis) leaf. This effort is directed towards improving micronutrients intake of the infants particularly the vitamin A and iron status since fluted pumpkin leaf is a good source of the nutrients. The leaf curd would be used as supplement to infant food.
1.3 OBJECTIVES OF THE STUDY
The general objective of the study was to evaluate the fluted pumpkin leaf curd as possible ingredient for the formulation of complementary food.
The specific objectives were to:-
- develop leaf curd from fluted pumpkin leaf.
- determine the nutrient composition of differently processed fluted pumpkin leaf (sun and shade-dried fluted pumpkin leaf and the curd).
- determine the effect of the processed leaves on the beta carotene, iron, ascorbate, zinc, copper and calcium status of rats.
- SIGNIFICANCE OF THE STUDY
The study will provide baseline information on the beta carotene and iron nutritional value of pumpkin leaf curd for its possible use as ingredients for infant food formulation.
The study will shed more light on processing methods that could be used to reduce bulk of locally available vegetables for use in infant feeding. The work will highlight the contribution of leaf curd as possible means of increasing micronutrient density of the locally available vegetables particularly their vitamin A (pro-vitamin A) and iron levels. Such vegetables if used on infant food formulation would increase nutrient intake without necessary increase in dietary bulk.
