Complete Material Cost #3,000
Order for Complete Material now
ABSTRACT
Microbial profile of unbranded vegetable oil was investigated in this resent study. Three vegetable oil samples were collected and examined. Microbiological analysis carried out revealed the total heterotrophic bacterial count (THBC) and total heterotrophic fungal count (THFC) To range between 6.0×107 CFU/ml and 4.6×107 CFU/ml, and from 1.6×108 CFU/ml and 2.1×108 CFU/ml for THFC and THBC respectively. The bacteria genera isolated were Escherichia sp, Bacillus sp, Micrococcus sp, Proteus sp, Streptococcus sp, Staphylococcus sp, Clostridium sp, Klebsiella sp, Pseudomonas sp and the fungal genera include; Mucor sp, Penicillum sp, Rhizopus sp, Candida sp and Yeast. This study revealed that unbranded vegetable oil has THBC and THFC far above the World Health Organization and the National Agency for Food and Drugs Administration and Control approved guidelines, and most of these organisms isolated are pathogenic in nature. Hence, critical control points should be identified during production, handling and distribution of vegetable oils with strict regulatory measures applied by regulatory agencies.
TABLE OF CONTENTS
TITLE PAGE- – – – – – – – – i
DECLARATION – – – – – – – – ii
CERTIFICATION- – – – – – – – – iii
DEDICATION- – – – – – – – – iv
ACKNOWLEDGEMENT- – – – – – – – v
ABSTRACT- – – – – – – – – – vi
TABLE OF CONTENTS- – – – – – – – vii
LIST OF TABLES- – – – – – – – – ix
SYMBOLS- – – – – – – – – – x
CHAPTER ONE
1.0 INTRODUCTION- – – – – – – – 1
1.1 BACKGROUND OF THE STUDY- – – – – – 4
1.2 STATEMENT OF PROBLEM- – – – – – 5
1.3 OBJECTIVES OF THE STUDY- – – – – – 6
1.4 SIGNIFICANCE OF THE STUDY – – – – – 6
1.5 SCOPE OF THE STUDY- – – – – – – 7
CHAPTER TWO
2.0 LITERATURE REVIEW- – – – – – – 8
2.1 EXTRACTION OF VEGETABLE OIL- – – – – 8
2.1.1 EXTRACTION BY PRESSURE- – – – – – 9
2.1.2 EXTRACTION BY LIQUID- – – – – – 9
2.2 MANUFACTURING PROCESS OF VEGETABLE OIL- – 9
2.2.1 MECHANICAL EXTRACTION- – – – – – 10
2.2.2 DEODORIATION/SPARGING- – – – – – 10
2.3 TYPES OF OIL- – – – – – – – 11
2.3.1 ESSENTIAL OIL- – – – – – – – 11
2.3.1.1 USES OF ESSENTIAL OIL- – – – – – 12
2.3.2 HYDROGENATED OIL- – – – – – – 13
2.3.2.1 USES OF HYDROGENATED OIL- – – – – 14
2.4 LIMITING FACTORS IN THE INDUSTRIAL USE OF
VEGETABLE OIL- – – – – – – – 14
CHAPTER THREE
3.0 METHODOLOGY- – – – – – – – 16
3.1 COLLECTION OF SAMPLES/MATERIAL- – – – 16
3.2 STERILIZATION OF GLASSWARES- – – – – 17
3.3 PREPARAYION OF MEDIA- – – – – – 17
3.3.1 PREPARATION OF NUTRIENT AGAR- – – – 18
3.3.2 PREPARATION OF MAC CONKEY AGAR- – – – 18
3.3.3 PREPARATION OF POTATO DEXTROSE AGAR- – – 19
3.4 ISOLATION OF TEST ORGANISMS – – – – – 19
3.4.1 PREPARATION OF DILUENT- – – – – – 19
3.4.2 SERIAL DILUTION- – – – – – – 20
3.4.3 PROCEDURE FOR ISPLATION- – – – – 20
3.5 CULTURE PURIFICATION AND CHARACTERIZATION- – 20
3.6 CULTURE STORAGE- – – – – – – 21
3.7 IDENTIFICATION OF COLONIES- – – – – 21
3.7.1 PREPARATION OF SUGARS- – – – – – 21
3.7.2 GRAM STAINING PROCEDURES- – – – – 22
3.7.3 BIOCHEMICAL TESTS- – – – – – – 22
CHAPTER FOUR
4.0 RESULTS- – – – – – – – – 29
4.1 DISCUSSION- – – – – – – – 32
CHAPTER FIVE
5.0 CONCLUSION AND RECOMMENDATION- – – – 34
5.1 CONCLUSION- – – – – – – – 34
5.2 RECOMMENDATIONS- – – – – – – 35
REFERENCES- – – – – – – – 36
APPENDIX- – – – – – – – – 38
CHAPTER ONE
1.0 INTRODUCTION
Oils constitute one of the essential components o balanced diets as good source of energy as well as complementing the energy needs of the society as biodiesel. Oil is considered contaminated or unsafe if a substance or condition is present that render the oil useless for a particular purpose. E.g. oil when consumed by human is considered contaminated when it contains pathogens or toxic substances. Oil that is contaminated for human consumption can be used in making biodiesels and plastics.
The term “vegetable oil” can be narrowly defined as or referring to plants oil only that is liquid at room temperature or broadly defined without regard to a substance state of matter at a given temperature. For this reason, vegetable oils that are solid at room temperature are sometimes called vegetable fats. Vegetable oil is a triglyceride extracted from a plant; such oils have been part of human culture for millennia.
The quality of vegetable oil is a measure of identity and edibility. This is also related to the method of obtaining the oils from vegetable source (i.e. whether it is virgin oil or cold pressed oil) both obtained without altering the nature of the oil, by mechanical procedures (e.g. expelling or pressing), and the application of heat. This may be purified by washing with water, settling, filtering and centrifuging only (Codex, 2015).
Vegetable oil sources include coconut, cotton seed, groundnut, maize germ, mustard seed, palm nut, sesame seed; soya beans and sunflower seed. According to Codex (2005), vegetable oils are “foodstuffs which are composed primarily of glycerides of fatty acids being obtained only from vegetable sources. They may contain small amounts of other lipids such as phosphatides of unsaponifiable constituents and of free fatty acids naturally present in the fat or oil”.
There is need to carry out microbial profile and quality assessment of unbranded vegetable oil in Port Harcourt major markets. This would provide the basis for maintenance for some standard for unbranded vegetable oil. Oil can be perfectly clear, tasty, have a golden yellow colour and yet be unsafe for human consumption.
Contaminants that pollute oils are classified into three (3) categories namely;
- Chemical
- Physical
- Biological
The pathogens most frequently transmitted through oils are those which cause intestinal tract congestions, heart disease and cancer.
In living plants and animals’ fats, carbohydrates and proteins are synthesized in a complicated series of steps with the aid of certain enzymes. These enzymes are capable of assisting the reverse as well as the forward reactions and hence under proper conditions may promote the degradations of the very substance that have previously been instrumental in synthesizing (Duka, 1993).
Oils in general are known to be susceptible to microbial attack. The composite of the various oils determines the extent and types of organisms likely to thrive in them. They are also known to support the growth of fungi and bacteria since it contains moisture.
When vegetable oil is contaminated with any pathogen such that bacteria, fungi and protozoans are usually present, it is usually tested for faecal contamination by isolating Escherichia coli to determine if the vegetable oil sample has faecal contaminants. Escherichia coliare called indicator organisms because it is a natural habitat (normal flora) of the human intestinal tract. Presence in oil indicates that the oil is contaminated with faecal material. Vegetable oil safe for human consumption should be free from disease producing microorganisms and chemical substance harmful to human health.
Manufacturing and purification method of this vegetable oil depends on the source of oil, use of the oil and amount of oil needed. Vegetable oil from a particular type of plant such as olive tree will require very extensive treatment to make it safe for consumption.
1.2 BACKGROUND OF THE STUDY
Vegetable oil constitutes a significant part of human diet as source of energy, fat soluble vitamins and essential fatty acids (FAO, 2009). They are extracted from seeds and nuts of various plants and are composed mainly of triacylglycerol. Studies have revealed that over the years, about 200,000 Nigerians have been dying yearly from various forms and levels of food poisoning, and unhealthy cooking oil is one of them, more are suffering from several diseases. Day by day, residents in Port Harcourt are buying and consuming more quantities of the unhealthiest (due to high cholesterol and fat content) form of unbranded vegetable oil. These unbranded vegetable oils sold in Port Harcourt are packaged in used or oil jerry cans, used bottle water cans, used plastic Coca-Cola containers, no content details are written on them, most of packaging done under unhygienic conditions. These used containers can contain over 5million germs sticking to the bottle neck alone (another 15million or more exploring the bottom). Washing thoroughly with hot water will only kill a one third of that amount leaving the rest dissolve into the oil.
1.3 STATEMENT OF THE PROBLEM
A number of shopkeepers in the markets of Port Harcourt are selling unbranded vegetable oil which, according to health experts may pose serious threats to the health of the general public. Bio deterioration covers a wide range of biological activities where the effect is to make things worse and this adversely affect man’s health and economy. Microorganisms known to cause chemical characteristics that lead to deterioration in quality and quantity of vegetable oils are derived from the seeds or fruits of plants. The keeping qualities of these oils are basically dependent on the chemical compositions for instance, the percentage of the degree of unsaturation (Gilbert et al., 1997).
Some slight deterioration at least is to be expected in any commercial oil bearing material and is in fact, inherent in the processes by which fat is formed.
Branded vegetable oil costs twice more than it did four (4) years ago, so it is even more difficult to get it now than ever.
1.4 OBJECTIVES OF THE STUDY
In this work, the term unbranded vegetable oil (UVO) is used to indicate or refers to locally produced and extracted edible vegetable oil without branding. This was obtained specifically from the raw materials processed in Port Harcourt, Nigeria. Thus, this work is carried at determining the microbial load of these unbranded vegetable oils with the following objectives:
- To determine the bacterial and fungal loads of these unbranded vegetable oil.
- To isolate and identify the various fungi and bacteria genera present in these vegetable oils.
- To compare the result with the approved World Health Organization (WHO) and National Agency for food and Drug Administration Commission (NAFDAC) standard.
1.5 SIGNIFICANCE OF THE STUDY
The importance of this study is to isolate and identify microorganisms associated with unbranded vegetable oil from various markets in Port Harcourt. The major activity is the necessity to examine the quality of this unbranded vegetable oils on the level of bacterial and fungal properties in Port Harcourt major markets of Rivers State. It also gives a summary of the level of these properties investigated/examined in the randomly selected market sites within the study area leaving consumers informed of these facts.
1.6 SCOPE OF THE STUDY
The scope of this research work covers microbial profile of unbranded vegetable oil samples obtained from three (3) randomly selected markets in Port Harcourt, Rivers State.