MICROBIOLOGICAL EVALUATION OF RAW AND SMOKED PORCUPINE MEAT CONSUMED
ABSTRACT
The microbiological status of raw and smoked porcupine meat sold in Benin City were investigated. The samples (raw and smoked porcupine meat) were sourced from three different locations (Egor, Ovia North-east and Oredo L.G.As) in Edo State. Bacteria growth was determined using nutrient agar, the presence of Streptoccocus aureus was detected and Fungi growth was determined by using potato dextrose agar. The culturing and isolation of each smoked and raw porcupine meat samples was done by putting one gram of each smoked and raw porcupine meat in 10ml of sterile distilled water.1ml was pipetted from it and added to next distilled water, making a dilution of 10-2.Dilutions were made by mixing 1.0ml of the homogenate in 9.0ml of sterile distilled water to obtain 10-3 dilution. Total viable counts of bacteria were determined by enumerating the colony forming units ( cfu/g) by pour plating 1.0ml of 10-1 and 10-2 diluents on nutrient agar plates supplemented with anti-fungi mixture to inhibit fungi growth and incubated at 370C for 48 hours. Total fungi counts were determined by pour plating Potato Dextrose Agar plates supplemented with antibiotic mixture to inhibit bacterial growth and incubated at room temperature ( 26±2oC) for 72 hours.The experiments were carried out in triplicates. Pure cultures of bacterial and fungal isolates were obtained on the Nutrient Agar and Potato Dextrose Agar respectively.
Microbiological analyses of the smoked porcupine meat indicates that the mean values of Bacteria count ranged from 6.20 x 102 cfu/g to 3.54 x 103 cfu/g for smoked porcupine meat samples and 2.58 x 103 to 1.44 x 102 cfu/g for raw porcupine meat samples and the mean values of fungi count ranged from 2.00 x 102 cfu/g to 3.36 x 103 cfu/g for smoked porcupine meat samples and 2.24 x 103 cfu/g to 1.15x 102 cfu/g raw porcupine meat samples. Six genera of bacteria and five genera of fungi were isolated. The samples from Egor LGA recorded the highest count with 3.54 x 103cfu/g and 2.58 x 103 cfu/g for smoked and raw porcupine meat samples respectively. The samples had no E. coli and other serious food-borne pathogens; such as Klebsiella sp. and Enterobacter. sp. It is worthy to note that the aerobic counts of bacteria and fungi were below that of the international food standard (< 105 cfu/g), the absence of E.coli and other serious food-borne pathogens indicates the microbiological safety of the products.
TABLE OF CONTENT
Title page———ii
Abstract———iii
Acknowledgement ——–iv
Certification———v
Dedication———vi
Table of Contents——–vii
List of Tables———x
List of Plates——–xi
CHAPTER ONE
1.0Introduction——–1
1.1Justification and Objective of Study—–2
CHAPTER TWO
2.0Literature Review——-4
2.1Porcupines——–4
2.2Porcupine Consumption and Popularity in Edo State—4
2.3Porcupine Diseases and Infestations—-6
2.4Food-borne Diseases——-6
2.5Food Poisoning——-7
2.5.1Allergic Reactions——8
2.5.2Food Intoxication——8
2.6Prevention of Food Contamination —–9
CHAPTER THREE
3.0Materials and Methods——10
3.1Samples Collections——-10
3.2Preparation of Media——-10
3.2.1Nutrient Agar for Bacteria Evaluation—10
3.2.2Potato Dextrose Agar for Fungi Evaluation—10
3.3Isolation of Microorganisms——11
3.3.1Isolation of Pure Cultures—–11
3.3.2Identification of Isolates—–11
3.4Gram Staining——–12
3.4.1Spore Stain——-12
3.5Biochemical Test——-12
3.5.1Oxidase Test——-12
3.5.2Catalase Test——-13
3.5.3Coagulase Test——13
3.5.4 Urease Test——-13
3.5.5Indole Test——-14
3.6Fungal Identification——-14
3.7Statistical Analysis——-14
CHAPTER FOUR
4.0Results———16
4.1Result on Microbial Analysis——22
CHAPTER FIVE
5.0Discussion——–23
5.1Discussion on Microbial Analysis—–23
CHAPTER SIX
6.0Conclusion and Recommendation—–25
References——–26
Appendix ———30
LIST OF TABLES
Table 4.1:Total Viable Bacterial Counts (cfu/g) of smoked
porcupine meat —–16
Table 4.2:Total Viable Fungal Counts (cfu/g) of smoked porcupine
meat ——-17
Table 4.3:Total Viable Bacterial counts ( cfu/g) of raw porcupine meat 18
Table 4.4:Total Viable Fungal counts ( cfu/g) of raw porcupine meat -19
Table 4.5:Cultural, Morphological and Biochemical Characteristics of the
Bacterial Isolates from Raw and Smoked Porcupine Meat 20
Table 4.6:Cultural and Microscopic Characteristics of the Bacterial
Isolates from Raw and Smoked Porcupine Meat –21
LIST OF PLATE
Plate 4.1:Serial dilution Process——41
Plate 4.2:Presence of Bacterial Isolates—–42
Plate 4.3:Microbial Isolation——43
Plate 4.4:Numbering of Sterile Petri-dishes—-44
Plate 4.5:Smoked Porcupine Meat—–45
CHAPTER 1
INTRODUCTION
Microbiological evaluation has been and continued to be a useful tool for determining the ability of a food (meat) to support the growth of spoilage organisms or pathogens. It also plays an important role in the validation of processes that are intended to deliver some degree of lethality against a target 0rganism or group of target organisms (Vasteergard, 2004).Porcupine meat (Raw and Smoked) potential shelf life can be determined through microbiological challenge studies. The evaluation of spoilage organisms or microbes can be on the increase in raw than smoked due to the latter having undergone processing as Pathogens do not survive under heat (Vesteergard,2004).Meat processing hygiene is a part of quality management of meat which refers to the hygienic measures to be taken during the processing steps in the manufacture of meat products (WHO,2002).Regulatory authorities usually provide the compulsory national frame work for food (meat) hygiene programmes through laws and regulations and monitor the implementation of such laws. Operations in meat processing plants comprises the manufacture of value added products from primary products of meat origin and non-meat origin such as Prof’s kilishi factory in University of Benin, Benin City (Igene.2009).There are three principles of meat hygiene which are crucial for meat processing operation: prevent microbial contamination of raw materials, intermediate (semi-manufactured) goods and final products during meat products manufacturer through absolute cleanliness of tools, working tables, machines as well as hands and outfits of personnels, minimize microbial growth in raw materials, semi-manufactured goods and final products storing them at a low temperature, Reduce or eliminate microbial contamination by applying heat treatment at the final processing stage for extension of shelf life products,(except dried and fermented final products which are shelf stable through low ph).However, processing of meat in Nigeria with reference to Edo state is in a high deplorable state(lgene,1984).The brush-tailed porcupine (Atherurus africanus) is a rodent species that occurs predominantly in the forests of equatorial Africa. It has an average body weight of 3kg and is a widely hunted and favoured protein source for both rural and urban populace In Nigeria ( Jori et al., 1998).In these regions, the porcupine meat frequently fetches higher prices than that from domestic or other game species. It is the most abundant bushmeat sold in Gabon. It reportedly accounts for 19% of the total species sold by the road side in Bendel States in Nigeria (Martin 1983, Colyn et al.,1987).However,current reports shows that porcupine is of low acceptance because of the bitterness of the meat making its counterpart species-grasscutter more readily acceptable by consumers in Edo State. Bitterness of porcupine meat is due to its consumption of local fruits called ‘’oosu’’ (Report from New Benin Market,2014).
1.1 JUSTIFICATION
It is important to know and evaluate the microbial population of porcupine meat consumed in Edo state because bacteriological studies showed that various bacteria which are potential pathogens inhabit different organs and tissues including lungs, liver, kidney, and stomach and the gastro-intestinal tract of African porcupine species and also those sold and processed in the markets are not well packaged for consumption, hence they are susceptible to microbial re-contamination after processing.
Disease-causing agents present in porcupine meat have been known for the cause of some health risk involving diseases and therefore, the need to employ some strategies towards evaluating the microbial load of this food commodity since it also helps in achieving food security as a mini-livestock. Due to high level of hunting of these species leading to a larger market of these products in Edo state, there is need for perpetual microbiological analysis and also to check contaminant in foods from the surrounding environment in order to know their risk levels and thus making the public aware on health risks in consuming raw or undercooked and under processed snail meat to prevent zoonotic diseases e.g Ebola. These organisms may remain in porcupines not as pathogens but as normal flora, but they can also cause diseases if eaten raw or improperly cooked, hence this study will help evaluate the various species of micro-organisms that are of public concerns.
This work will also help evaluate microbiological load before processing, after processing the quantity of micro-organisms that re-contaminate smoked porcupine meat sold for consumption in the various locations in Edo State where the study was conducted. This work will also examine the possible sources of contamination and re-contamination of porcupine meat sold in Edo State with respect to the zones or locations where the meat was purchased.
OBJECTIVES OF THE STUDY
The objectives of the study were to:
1. To evaluate the microbial population(cfu/g) of raw porcupine
2. To evaluate the microbial status of smoked ready-to-eat porcupine.
3.To compare the microbial status of raw and smoked porcupine meat.
MICROBIOLOGICAL EVALUATION OF RAW AND SMOKED PORCUPINE MEAT CONSUMED
