MICROBIAL QUALITY OF PALM WINE SOLD IN ELELE COMMUNITY
BY
ELUMA IFEANYI EMMANUEL
MB/12/032
BEING A PROJECT PROPOSAL
PRESENTED IN A PARTIAL FULFILMENT OF THE REQUIREMENT
FOR
THE AWARD OF BACHELOR OF SCIENCE (B.SC) DEGREE IN MICROBIOLOGY
DEPARTMENT OF MICROBIOLOGY
FACULTY OF SCIENCE
MADONNA UNIVERSITY NIGERIA, ELELE CAMPUS.
SUPERVISOR: DR IKEH
MAY, 2016.
CHAPTER ONE
INTRODUCTION
Palm wine is an alcoholic beverage produced only from the sap of certain species of palm trees. The palm wine is a major drink product from the palm tree and its production is popular especially in rural villages of certain countries and continents such as the Caribbean, African, Asia and South American. The palm wine sap is usually extracted and collected by a palm wine tapper and its mainly produced through fermentation of the sugary palm sap collected from palm trees. Palm tree is botanically known as arecacea and belongs to the family of palmaceae or palmae. Palm wine sap is mainly obtained from wild date palms, Palmyra, coconut palms, raffia palms, kithul palms, silver date palm and nipa palms (Nwokeke, 2011). According to Bassir (1982), palm wines major constitute are; carbohydrate, organic acid, protein, vitamin C and ash. There are various species of palm trees among which are Elias guineensis, Raphia regalis, R. sudanica, R.vinifera and R. hookeri (Obire, 2005).
1.1 SOURCE OF PALM WINE
This is gotten by tapping the top of the truck of the felling palm tree and boring a hole into the trunk. Sap is collected by tapping the palm. This is achieved by making an incision between the kernels and a gourd is tied around to collect the sap which is collected a day or two later. The fresh palm juice is a sweet, clear, colourless juice containing 10 -12% sugar and is neutral. The quality of the final wine is determined mostly by the conditions used in the collection of the sap (Okafor,1975).
1.2 MICROORGANISM PRESENT IN PALM WINE
The organisms responsible are mainly Saccharomyces cerevisiae and Schizosaccharomyces pombe and the bacteria Lactobacillus plantarum and Lactobacillus Mesenteroides. It’s reported that yeast and bacteria originate from the gourd, palm tree and tapping implements. However the high sugar content of the juice would seem to selectively favour the growth of yeasts which might originate from the air. This is supported by the fact that fermentation also takes place in plastic containers. Within 24hours the initial PH is reduced from 7.4-6.8 to 5.5 and the alcohol content ranges from 1.5-2.1%. The organic acids present are lactic acid, acetic acid and tartaric acid. The bacteria that are predominant in palm wine fermentation are micrococcus, leuconostoc, lactobacillus and acetobacter (Uzogara et al., 1990).
1.3 STATEMENT OF PROBLEM
Certain factors are responsible for palm wine contamination and these factors include; collection of palm sap with unwashed, repeatedly used instruments and storage condition. The numbers of genera of microorganism found in this kind of sap are high unlike those collected with sterile instrument. Although attempts have been made towards the preservation and shelf life extension of palm wine through bottling, use of chemical additives and addition of plant extrats have greatly affected the organoleptic quality of the product (Bassir et al.,2006)
1.4 AIMS AND OBJECTIVE
This is to determine the microbial quality of locally consumed palm wine sold in Elele community and to ascertain the microbial quality and several sources of contamination of palm wine sold.
1.5 SCOPE OF STUDY
This study is limited to palm wine tappers and palm wine bars in elele community targeting up to 20 samples.
1.6 SIGNIFICANCE OF STUDY
The result of this research will be able to inform and acquaint the general public on the microbial quality and also the nutritional properties of palm wine sold in Elele.
MATERIALS AND METHOD
1.7 COLLECTION OF SAMPLES
10 samples of palm wine will be collected from two different source in Elele which include drinking bar and palm wine tapper. A sterile container will be used to put the samples after which the sample will be taken to the laboratory in a covered container loaded with packs of freezing mixture of salt and ice block for microbial analysis within one hour of collection, this method is known to reduce effectively fermentation rate of the sample.(Bassire and Obire, 2006.)
1.8 PREPARATION OF DILUTION
About 9mls of normal saline will be dispensed into each of the ten series capped tubes using sterile 10mls pipette and they are sterilized for 15mins at 121c in an autoclave.
1.9 PREPARATION OF SAMPLE FOR BACTERIAL ENUMERATION ANALYSIS
After sterilization of the diluents 1ml of each suspension will be introduced into the test tubes using the tenfold serial dilution technique and labeled 10-2 .It will be thoroughly mixed by shaking tube with its capped closed properly, after which 1ml will be removed from the test tube labeled 10-2and dispensed in the one labeled 10-3 this dilution continues until the last tube labeled 10-10 where after mixing.1ml will be withdrawn and discarded (Cruickshank et al.,1995)
2.0 ENUMERATION OF MICROORGANISM
After tenfold serial dilution has been 0.1ml aliquots from 10-4 – 10-6 dilutions will be aseptically transferred on a petri dish and 18-20ml of nutrient agar will be poured on the Petri dish and swirled clockwise, anticlock wise and rocked up and down for distribution and will be left to solidify. The MacConkey agar plate will be use for the coliform count. Nutrient agar for total aerobic count. Eosin methylene blue for Escherichia coli count & potato dextrose agar plate will be use for fungal count & also for fugal isolation. The agar plate will then be inverted and allowed to stay for 60sec and excess stain was washed off in running water. Acetone will be used to flood the stain to decolorize the stain film for 25sec and immediately washed with running tap water and then will be counter stained with safarine red for 120sec. Finally the slides will be washed, blotted dry and observed under oil immersion objective of the microscope. The colour for gram negative organism is pink while colour for gram posistive organism is purple. (Cheesbrough,2003).
2.1 WET PREPARATION OF FUNGI
A needle will be used to smear some colonies on a clean grease free glass slide, this will then be stained lightly using lacto phenol cotton blue & cover with a cover slip & examined under the light microscope using x40 objective.
2.2 BIOCHEMICAL TEST
These test will be use in differentiation of isolated organism which are preserved on nutrient agar slant will be kept at room temperature & subcultured onto fresh nutrient agar to obtain fresh cultures, that will be used for biochemical test. Gram positive cocci would be tested with the catalase & coagulase test while gram negative rods would be tested on citrate indole test. Other test such as urease test, sugar fermentation test, determination of PH & alcohol content. Determination of acetic acid concentration will be done.
2.3 NUTRITIONAL ANALYSIS
This is the study and the determination of nutritional qualities of the sample under study (palm wine). The sample will be tested for various nutrients and the proportion they occur in the samples. The determination of the availability of the quality of nutrients such as carbohydrates & proteins. Also other qualities such as content & fiber are determined. This is especially an important role in determining the type of organism that can cause spoilage in them, thus giving room for better understanding of how foods can be handled and preserved (Buchons and Caibbons, 1994).
2.4 STATISTICAL ANALYSIS
Data obtained from this study will be analysed using the statistical package for social science (SPSS) version 18.0 for windows. Analysis or variance (ANOVA) and t-test will be use to compare means & values will be considered significant at p‹0.05. (Agwung-fobellah, 2007).
CONCLUSION
By the end of this research project the health benefits and microbial load of palm wine will be air to the public.
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