ASSESSMENT OF PERCENTAGE CHEMICALS PRESENT IN APPLE PEEL AND APPLE FLESH IN EXOTIC APPLE FRUITS FROM SELECTED MARKETS IN ILORIN, KWARA STATE, NIGERIA
ABSTRACT
Global production of apples is extremely high as its demands increased yearly, to meet this demand, the grower and marketer ensure that they maintain the quality of apple after harvest, during storage and delivery by using preservatives. This research provides information about the types and levels of chemical preservatives contained in exotic apple fruits being sold in Nigerian markets. Two different samples of apple (red and lemon) wereboughtfrom Oja-Oba market in Ilorin, Kwara Statefor analysis. The apples were peeled separately and juice was extracted using the fruit juice extractor. Analysis of the juices from the peel and fleshy part of the apple were carried out using n-Hexane and GCMS (Gas chromatography Mass Spectrophotometer). Out of seventeen chemicals identified in the juice from apple flesh, two chemicals were pronounced with high composition which are 3a, 4, 5, 6, 7, 7a-hexahydro-4,7-methanoindene (17.65%), hydroxymethylfurfural (11.76%), from the apple peels, two major chemicals were identified in apple peels which are 2,4 dihydroxy 2, 5- dimethyl-3 (2H)- furan-3-one(50%) and dodecane (150%).Chemical preservatives in fruit make consumers to be at risk of chemical ingestion, and revealed the presence and concentration of chemical preservatives in fruit that make consumers to be at risk of chemical ingestion.From the seventeen chemical preservatives identified in the apples samples, three chemicals were identified as beneficial which are basically used for apple wax while the other three pose less threat to health and the environment.
Key words: Apple, Peel, Juice, Chemical.
TABLE OF CONTENTS
Title page………………………………………………………………………………..i
Declaration………………………………………………………………………...........ii
Certification……………………………………………………………………..……...iii
Dedication……………………………………………………………………………....iv
Acknowledgement………………………………………………………………............v
Table of content………………………………………………………………...……....vii
Abstract………………………………………………………………………………….viii
1.0 INTRODUCTION………………………………………………………….………..1
1.1Statement of the problem……………………………………….…………………...4
1.2Justification of the study………………………………………………..……............5
1.3Research questions………………………………………………….……….………..6
1.4Aim and objectives……………………………………………………………............7
1.5Research hypothesis…………………………………………………..…………….....7
2.0 LITERATURE REVIEW………………………………………………………...........7
3.0 RESEARCH METHODOLOGY………………………………………....……...........22
3.1 Description of area of study……………………………………………………….…..22
3.2 Sample collection………………………………………………..……………….........23
3.4 Sample preparation………………………………………………………………….....24
3.5 Sample analysis……………………………………………………………………...…28
4.0 RESULT AND DISCUSSION……………………………………….……………...…29
5.0 CONCLUSION AND RECOMMENDATION…………………………...................…40
5.1 References……………………………………………………………………………....43
5.2 Appendices…………………………………………………………………………….. 45
CHAPTER ONE
1.0INTRODUCTION
Apple (Malusdomesticus) is one of the most widely cultivated tree fruit (Harris et al., 2007), and is generally believed to have originated from somewhere in Central Asia. It is the fourth most widely produced fruit in the world after banana, orange, and grapes (Aliet al., 2004).The apple is the most ubiquitous of temperate fruits and has been cultivated in Europe and Asia from antiquity. It was known to the Greeks and Romans and mentioned by Theophrastus in the third century B.C. Since then the apple has been distributed into almost all parts of the world. Apples are popular because of the many ways that they can be consumed and because of their convenience and durability.
Global production of apples is extremely high, indeed estimates by the Food and Agricultural Organization (FAO) suggested that in 2005 over 62 million Metric Ton were produced. Clearly in order to sell for premium (highest) prices, it is essential that growers produce the best quality fruit to international market standards - and then ensure that they maintain the quality after harvest, during storage and delivery. The leading countries in apple production are China, United States, France and Italy.Apple is consumed not only because of their flavor, but also because of their nutritional importance due to vitamins, dietary fibers, and rich phenolic content in comparison to other fruits (Suneet al.,2002).
Apple contains carbohydrates (13.9 g/100 g), fiber (0.8 g/100 g), proteins (0.4 g/100 g), lipid (0.3 g/100 g), ash (0.3 g/100 g), vitamin C (8 mg/100 g), sodium (0.3 mg/100 g), potassium (145 mg/100 g), calcium (7 mg/100 g), magnesium (6 mg/100 g), iron (480 μg/100 g), phosphorus (12 mg), and iodine (2 μg/100 m) (Hussain, 2001). Apples have very strong anti-oxidant activity mainly due to the polyphenols, such as quercetin, catechin, phloridzin, and chlorogenic acid present in them (Boyer and Liu, 2004). Due to high levels of phytochemcialspresent, consumption of apple is associated with reduction in cardiovascular diseases (Knektet al., 1996).
Apple consumption is also effective in treating infant intestinal disorders, such as diarrhea and dysentery (Considine, 1982). And helps in weight reduction in adults (Conceiçãoet al., 2003). Weight loss associated with a daily intake of three apples or three pears among overweight women. Apple is mostly consumed as fresh fruit, but due to its perishable nature, its quality deteriorates and cannot be stored for a long time. Quality of apple changes rapidly during storage that substantially affects the consumer acceptability (Vieira et al., 2009).
In order to preserve the fruit for longer periods, it is processed to different products, such as juices, jams, and jellies and even stored as pulp. The preservation techniques are aimed to slow down the changes that are caused by foods deterioration, due to large number of physical, chemical, enzymatic, or biological reactions (Gould,2000). Chemical preservation is the most commonly and widely used method among several methods of preservation because it is simple and economical. The chemical preservatives are used to prevent microbial contamination and thus are effectively used in combinations with other preservative techniques for increasing the shelf life. No single chemical preservative is completely effective against all micro-organisms (Chiply, 1983). Sodium benzoate (SB) and potassium metabisulphite (KMS) are commonly used as preservatives for long-term storage of fruit pulp because of their better antimicrobial activity and prevention of browning (Lueck, 1990).
Majority of foods available in the market contain different types of additives, among which preservatives are playing an important role. These additives, applied in order to maintain:food quality, reduce food deterioration and prolong storage time (Daniel, 2007). Fruits are important components of the human diet since they provide essential nutrients that are required for most of the reactions occurring in the body.A high intake of fruits has been encouraged not only to prevent consequences due to vitamin deficiency but also to reduce the incidence of major diseases such as cancer, cardiovascular diseases and obesity.
In order to reduce the loss and maintain the quality of fruits additives especially preservatives are applied (Pandey and Upadhyay, 2012).Fruit which is over-fortified with additives such as preservatives, antioxidants, and sweeteners, etc. could adversely affect human health as they are consumed (Dhatt and Mahajan, 2007).
Therefore, the identification and quantification of chemical preservatives in fruits are important in terms of food safety and disease prevention.
According to (Dhatt and Mahajan, 2007), postharvest handling is the stage of production immediately following harvest. The instant an apple is separated from its parent plant, it begins to deteriorate. Postharvest treatment largely determines final quality. The most important goals of postharvest handling are keeping the product cool, to avoid moisture loss and slow down undesirable chemical changes, and avoiding physical damage such as bruising, to delay spoilage.Processes in postharvest handling includes;
I. Packing house operation: dumping, pre-sorting, washing and cleaning, sizing and grading.
II. Precooling:room cooling, forced air cooling, hydrocooling, package icing.
III. Treatment:washing with chlorine, ethylene inhibitors/growth regulators/fungicide treatment, calcium application, thermal treatment, fumigation with SO2, irradiation, waxing.
Chemical preservatives
Chemical food preservatives are those substances which are added in very low quantities (up to 0.2%) and which do not alter the organoleptic and physico-chemical properties of the foods.Preservation of fruit products containing chemical preservatives is usually based on the combined or synergistic activity of several additives, intrinsic product parameters and extrinsic factors (Pandey and Upadhyay, 2012).
1.2 Statement of the problem
Preservatives in fruits are designed to prevent bacteria growth and spoilage, but sometimes they can also prevent consumers from enjoying good health. Many studies revealed reported cases of harmful effects of chemical preservatives in fruits which include breathing difficulties, cancer, behavioural changes, heart damage, obesity, infertility, etc. (Tuula,2009).
Apple fruits are visible in most of the fruit stalls and supermarkets inIlorin Kwara State, Nigeria, and the consumption pattern is also increasing by the day. However, there are growing public health concerns among the general populace about the safety of exotic apple fruit due to increased awareness especially from the social media on the Abuse of chemical preservatives on fruit and there is little effort towards addressing this in the country.
This research provides information about the types and levels of chemical preservatives contained in exotic apple fruits.
1.3 Justification of the study
The study would be useful in unveiling the different types and levels of chemicals used in preserving exotic apples before they arrive Nigerian markets for consumption. Information from this study can be used by relevant regulation in tracking non-compliance with permissible limits of chemical preservatives on fruits. Concerns raised by consumers on their safety would also be addressed.
1.4 Research questions
1. Are there chemicals on exotic apple fruits found in Nigerian markets?
2. Are the chemicals in higher level or not?
1.5 AIM AND OBJECTIVES
1.5.1 Aim
To determine the types and compositions of chemicalscontained in exotic apples from selected market in Ilorin, Kwara State, Nigeria.
1.5.2 Objectives
1. To identify the types of chemicals found in exotic apple fruits sold in selected markets in Ilorin, kwara state Nigeria.
2. To determine the composition of these chemicals in the exotic apple fruits.
1.6.1 Research hypothesis
1.6.2 Null hypothesis
1. Ho: There are no chemical preservatives on exotic apple fruits found in both SHOPRITE supermarket in Ilorin and from market within Ilorin.
2. Ho: There are no chemical preservatives at higher levels on exotic apple fruits found in Ilorin Markets.
1.6.3 Alternative hypothesis;
1. H1: There are chemical preservatives on exotic apple fruits found in Ilorin Markets.
2. H1: There are chemical preservatives at higher levels on exotic apple fruits found in Ilorin Markets.
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