Determination of Nutritional Composition and Antioxidant Properties of Selected Local Fruits

CHAPTER ONE

1.0 Background of the Study

Fruits are essential components of a balanced diet because they provide vitamins, minerals, and dietary fiber that support good health. They also contain natural antioxidants that protect the body against oxidative stress and related disorders (Slavin & Lloyd, 2012).

The nutritional composition of fruits varies depending on the species, maturity, and environmental conditions. These differences influence their health benefits and potential for industrial use. Many local fruits in Nigeria are underutilized despite being rich in nutrients and bioactive compounds. Scientific evaluation of their nutritional and antioxidant properties can help increase their consumption and economic value (Oduro et al., 2009).

Antioxidants found in fruits play a key role in neutralizing free radicals. These unstable molecules cause cell damage that leads to chronic diseases such as cancer, diabetes, and heart disease (Lobo et al., 2010). Regular consumption of fruits rich in antioxidants improves overall health and strengthens the immune system.

In Lagos, Nigeria, a wide variety of local fruits such as pawpaw, mango, guava, and African star apple are available throughout the year. However, the nutritional and antioxidant composition of many of these fruits remains poorly documented. Therefore, this study seeks to determine the nutritional composition and antioxidant properties of selected local fruits in Lagos, Nigeria.

1.1 Statement of the Problem

Although Nigeria is blessed with many indigenous fruits, most people still prefer imported varieties. This preference is often due to inadequate knowledge of the nutritional and antioxidant potential of local fruits. As a result, many nutrient-rich fruits are underexploited and wasted.

In addition, cases of malnutrition and non-communicable diseases are on the rise. Promoting the consumption of locally available fruits with proven nutritional and antioxidant benefits can help address these health challenges. Hence, there is a need for scientific evaluation of the nutritional and antioxidant properties of selected local fruits in Lagos.

1.2 Aim and Objectives of the Study

Aim:
To determine the nutritional composition and antioxidant properties of selected local fruits in Lagos, Nigeria.

Objectives:

1. To identify and select commonly consumed local fruits in Lagos.

2. To determine their proximate composition, including moisture, protein, fat, and carbohydrate contents.

3. To analyze their vitamin and mineral content.

4. To evaluate their antioxidant properties using standard assays.

5. To compare the nutritional and antioxidant profiles among the selected fruits.

1.3 Significance of the Study

This study provides valuable information on the nutritional and antioxidant properties of selected local fruits in Lagos, Nigeria. The findings will help promote their consumption and improve public awareness of their health benefits.

Furthermore, the results will assist food industries and nutritionists in developing fruit-based products. It also encourages farmers to cultivate and preserve indigenous fruit species, contributing to national food security and economic growth.

1.4 Scope of the Study

The study focuses on selected local fruits such as pawpaw (Carica papaya), mango (Mangifera indica), guava (Psidium guajava), and African star apple (Chrysophyllum albidum) commonly found in Lagos. Laboratory analysis includes proximate composition, vitamin and mineral determination, and antioxidant assays such as DPPH and FRAP tests. Post-harvest and storage studies are excluded from this research.

1.5 Definition of Terms

Antioxidant: A compound that prevents or delays oxidation by neutralizing free radicals.
Nutritional Composition: The analysis of nutrients such as protein, fat, carbohydrate, vitamins, and minerals in a food item.
Phytochemicals: Naturally occurring plant compounds that provide health benefits.
Free Radicals: Unstable molecules that can cause oxidative damage to body cells.
Proximate Analysis: A basic method used to determine the main nutrient components of food, such as moisture, ash, protein, and fat.
Local Fruits: Indigenous fruits grown and consumed within a specific region, such as Lagos, Nigeria.