Comparative Analysis Of Selected Soft Drinks (With Reference To Physiological Analysis, Ph, Sugar-Glucose Content, Acidity, Carbonate, Metals Present)

Soft drinks are sold and consumed daily in Nigeria due to its affordability, characteristic taste, and thirst quenching potential. However, the high demand may compromise the quality of production with possible contamination of heavy metals and excessive constituents which have shown to cause intoxication and death in humans. This study evaluated some constituents of twenty-six soft drinks in Nigeria and investigated the presence of some heavy metal contaminants. The soft drinks were screened for the presence of sugar, carbon dioxide, phosphate and alcohol as well as the pH and acidity determined. The level of cadmium, mercury and lead were determined using atomic absorption spectrophotometer. The study showed the presence of sugar, carbon dioxide, phosphate, and alcohol in the soft drinks. The soft drinks were acidic in nature, pH ranging from 3 to 5 with a mean of 3.6 and the acid concentration was relatively low between 3 and 12 g/L with a mean of 8.1 g/L. Lead was present in all the samples ranging from 0.17 to 3.39 mg/L with a mean of 0.8, mercury was present in 22 samples ranging from 0.29 to 11.32 mg/L with a mean of 2.08 mg/L while cadmium was present only in one sample (0.149 mg/L). When compared to EPA, WHO and NIS standards, the levels of the heavy metal contaminants were above the tolerated limits for good quality drinking water in most samples. These results suggest that soft drinks in Nigeria may be contaminated with heavy metals which constitute a major public health problem. Thus, quality control is recommended during the production process especially at the stages of sterilization and purification.

TABLE OF CONTENTS

COVER PAGE

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

CHAPTER ONE

• • INTRODUCTION

• • BACKGROUND OF THE PROJECT

• • PROBLEM STATEMENT

• • AIM AND OBJECTIVE OF THE PROJECT

• • SCOPE OF THE PROJECT

• • SIGNIFICANCE OF THE PROJECT

• • LIMITATION OF THE PROJECT

• • METHODOLOGY

• • PROJECT ORGANISATION

CHAPTER TWO

LITERATURE REVIEW

• • OVERVIEW OF HEAVY METALS

• • REVIEW OF THE STUDY

• • REVIEW OF CADMIUM, LEAD AND MERCURY

CHAPTER THREE

MATERIALS AND METHODS

• • TEST FOR SUGAR

• • TEST FOR REDUCING SUGAR

• • TEST FOR PHOSPHATES

• • TEST FOR ALCOHOL

• • TEST FOR CARBON DIOXIDE

• • QUANTIFICATION OF ACID CONCENTRATION

• • DETERMINATION OF PH

• • QUANTIFICATION OF HEAVY METALS

3.8.1. Sample preparation

3.8.2. Preparation of metal ion and ASS analysis

3.8.3. Analysis for heavy metal contamination in soft drink

3.9. STATISTICAL ANALYSIS

CHAPTER FOUR

• • RESULTS

• • DISCUSSION

CHAPTER FIVE

• • CONCLUSION

• • REFERENCES

CHAPTER ONE

1.0                                          INTRODUCTION

1.1                            BACKGROUND OF THE STUDY

In Nigeria today, soft drink is one of the most consumed beverages. The consumption of non-alcoholic beverages in Nigeria was rated at 159.85 g/person/day in 2007 [FAO, 2011]. Soft drinks exist in various forms and brands and are marketed by different brewery industries across the country [I.F. Asiegbu, 2011]. These drinks are readily consumed on daily bases especially when undergoing tedious activities like hard work and sport. Also, with the relatively affordable prices, they are highly consumed during leisure and relaxation outings and serve the general public in celebrations such as traditional marriages, weddings, funerals, etc. [EFSA, 2016].

The high consumption rate of soft drink is attributed to the characteristic taste and flavour as well as their thirst quenching potential [B.B. Phillip, 2013]. These characteristics are defined by the constituents present such as sugar which is responsible for its sweetness, carbonated water which is water compressed with carbon dioxide to make it an ultimate thirst quencher and flavouring agents to add flavour to the drinks. In addition to taste satisfaction, soft drinks contain other constituents such as vitamins, phosphates, acids, antioxidants, etc. which are of nutritional and health benefits to the body (G.M. Pofahl , 2005).

However, due to the high level of consumption and demand of soft drinks, quality control within the process of production especially during sterilization and purification may be compromised and the quality of soft drinks may be challenging. As such, soft drinks have been shown to contain traces of alcohols as a result of microbial contamination. Also, the presence of some heavy metals such as cadmium, lead, mercury arsenic, zinc, etc. in soft drinks which may be due to environmental pollution from surface and underground water, food and fruits utilized during production have been reported.

Heavy metals are metals that have shown to be harmful and toxic to the human body and constitute a major public health concern. These metals have the potential of causing acute and chronic toxicity by various modes of action in both children and adults. Some heavy metals act as catalyst in oxidative reactions of biological macromolecules, therefore their intoxication may lead to oxidative tissue damage. Others have genotoxic/carcinogenic potential causing chromosomal aberrations and mutation as well as cancer. One of the major mechanisms by which heavy metals exert toxic effect is through impairment of cellular respiration by inhibition of various mitochondrial enzymes, and the uncoupling of oxidative phosphorylation. Some of the heavy metals of health importance include: cadmium, lead, mercury, etc. (C. Rubio, 2016).

Cadmium is a heavy metal whose long term accumulation may lead to cancer since it is a carcinogenic element [C. Rubio, 2016]. Also, over a long period of intake, cadmium may accumulate in the kidney and liver because of its long biological half life and may lead to kidney damage. Lead is known to affect humans and animals of all ages but the effects of lead are most serious in young children. The most common childhood presentation of lead poisoning is central neurotoxicity. Other symptoms of childhood lead toxicity include; anaemia, peripheral motor neuropathy, gastrointestinal complaints such as anorexia, vomiting, and abdominal pain, and growth delay. Mercury is also another critical health hazard. Its intoxication can occur in infants and adults and has shown to interfere with numerous cellular processes including protein and nucleic acid synthesis, oxidative stress, calcium homeostasis, and protein phosphorylation.

Thus, this study was aimed to evaluate some constituents of soft drinks in Nigeria which may be characteristic of their taste and consumption and also assessed some heavy metal for possible contamination.

1.2                                   PROBLEM STATEMENT

There have been reports of the presence of heavy metals, pH, sugar-glucose content, acidity, and carbonate at a concentration above the limit specified by the World Health Organization (WHO) for food and drink products in Nigeria. This work was designed to compare the levels of zinc, copper, lead, cadmium, pH, sugar-glucose content, acidity, and carbonate in selected Nigerian soft drinks with the specified recommended limits by the World Health Organization. These heavy metals in selected Nigerian soft drinks were estimated by Atomic Absorption Spectroscopy after digestion of soft drinks with nitric acid.

1.3                          AIM / OBJECTIVE OF THE STUDY

The main aim of this work is to determine the levels of pH, sugar-glucose content, acidity, carbonate, metals present in some selected. The objectives of this project are:

• • To find out the level of heavy metals in soft drink.

• • To find out the level of other constituents such as pH, sugar-glucose content, acidity, carbonate in soft drink.

• • To ensure that soft drink is safe for human consumption

• • To ensure that soft drinks are up to WHO standard.

1.4                                    SCOPE OF THE STUDY

This study highlight the importance of soft drink consumption and how it can be produced to meet up with WHO standard by ensuring they are free from heavy metals and by ensuring that they contain a moderate level of pH, sugar-glucose content, acidity, carbonate which are recommended by WHO.

1.5                             SIGNIFICANCE OF THE STUDY

This research work will throw more light on the best techniques for ensuring that soft drinks are safe for human consumption.

It also throw light on the standard recommended by WHO for soft drinks in other to ensure a safe soft drink.

Finally, it will also serve as a useful piece of information for both producers and consumers in that it will help them to be very careful and when producing or consuming soft drinks.

1.6                                                  LIMITATION OF STUDY

As we all know that no human effort to achieve a set of goals goes without difficulties, certain constraints were encountered in the course of carrying out this project and they are as follows:-

1. 1. Difficulty in information collection: I found it too difficult in laying hands of useful information regarding this work and this course me to visit different libraries and internet for solution.

1. 1. Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).

• • Time Constraint: The researcher will simultaneously engage in this study with other academic work. This consequently will cut down on the time devoted for the research work.

1.7                                             RESEARCH METHODOLOGY

In the course of carrying this study, numerous sources were used which most of them are by visiting libraries, consulting journal and news papers and online research which Google was the major source that was used.

1.8                                     PROJECT ORGANISATION

The work is organized as follows: chapter one discuses the introductory part of the work, chapter two presents the literature review of the study, chapter three describes the methods applied, chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.