ASCORBIC ACID CONTENT OF ORANGE AND VEGETABLE (PUMPKIN) OBTAINED FROM OGBETE, ENUGU STATE UNDER DIFFERENT STORAGE CONDITIONS

ABSTRACT                        

The ascorbic acid (vitamin C) of fruits (orange) and vegetable (pumpkin) was estimated after storage for three days under different temperatures. The storage conditions were deep freezing temperature, domestic refrigeration temperature, storage in dark cupboard and open shelf both at room temperature and finally exposure to sunlight outdoors. The titrimetric method using 2,6-dichlorophenol idophenol was employed. The titres were obtained for each titration and the results averaged. Chloroform in a very small amount was used to aid the observation of the titraphy which interferes with the colour of the titration end point. The result showed decrease in the ascorbic acid content of food stuffs over the storage period of three days. The degrees were expressed as percentage loss of original fresh materials viz: refrigerated (domestic) sample (6-22%); Deep frozen (0.99-2.82%); Dark cupboard storage (12 – 26.66%); Room temperature (Open shelf) sunlight 16.69 – 23.35%); and finally outdoor sunlight exposed sample (19.09 – 29-33%).

CHAPTER ONE

INTRODUCTION

1.1     BACKGROUND OF THE STUDY

Vitamin C (ascorbic acid) appears to have been the first nutrient to be associated with major outbreak of disease Stewart et (2002). Even primitive tribes know that insufficient consumption of fresh food, particularly fresh fruits and vegetables for several months would become sick and may ultimately die with the symptoms characteristics of scurvy. Although very unstable under most circumstances, this vitamin was one of the first to be identified in crystalline form as pure substance, Freed (1999) commercial production with high yield form glucose Burn et al  (2000).

Apparently all form of life, both plants and animals with the possible exception of simple forms through such as bacteria that have not been studied through either synthesized the vitamin form other nutrient or require it as a nutrient. Dormant seed contain no measurable quantity of the vitamin is formed

Except for synthetic supplies the most universal requirement for fresh food as a source of vitamin C is readily explained  by the extreme sensitivity of vitamin C to destruction by reaction with oxygen in the air. This tendency is generated by the presence of minute quantities of enzyme that occur in most living tissue in which copper or iron is combined with protein to form a catalysts for the reaction of vitamin C with oxygen. Many other chemicals such as quinines or high tendency of salts of manganese, chromium and iodine can also oxidize the vitamin readily in aqueous solutions. Most of these reactions increased in proportion on exposure to air and rising temperature. Encyclopedia Britanica (2oo1).

Ascorbic acid on oxidation produced dehydroascorbic acid which is much less stable than ascorbic acid and tends to yield products such as oxalate threonic acid and carbon dioxide. When administered to animals or consumed in food dehydro-ascorbic acid has almost the same antiscorbutric activity as ascorbic acid. It can be quantitatively reduced to ascorbic acid. Encyclopedia Britannica (2000 – 2009).

In its biochemical function ascorbic acid clearly acts as a regulator in tissue respiration and may serve as antioxidant in vitro by reducing oxidizing chemicals. Ascorbic acid also participate in a number of reaction systems such as glutathione system of oxidation and reducing and also there is a strong evidence that electron transfer reaction involving ascorbic acid are characteristics of animal systems.

Pauling et al (1995), championed the administration of mangadose (gram quantities rather than mg quantity as recommended by nutritionist) not just in treating scurvy but also against common cold and maintaining the good health necessary to avoid other illness as cold. Nutritionist to not support these claims advocating that in milligram quantities provides the body tissues with saturating levels of the vitamin as excessive amount of consumed vitamin C being water soluble are not maintained or stored in the body but are excreted.

1.2     STATEMENT OF THE PROBLEM

Many people are suffering from different kinds of diseases as a result of inadequate intake of ascorbic acid such problem include scurvy. This has prompted the lead to project work to be carried on the determination of ascorbic acid content of some natural fruit and vegetable such as orange and pumpkin and also to recommend  on the daily intake of orange and pumpkin.

1.3     AIM AND OBJECTIVES OF THE STUDY

To identify ascorbic acid content of orange and pumpkin under different storage conditions.

To identify the percentage loss of ascorbic acid under different storage conditions.

1.4     SIGNIFICANCE OF THE STUDY

The significance of this work is to study the effects of vitamin C supplement (250/day).

To study the impact of antioxidant suppimentation on aortic stenoisis, an age associated heart value disorder that have an inflammatory component

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