ISOLATION AND CHARACTERIZATION OF BACTERIA ASSOCIATED WITH HAWKED SUYA-MEAT IN ENUGU METROPOLIS
This project work was carried on the isolation and characterization of pathogenic bacteria from hawked suya meat. Suya meat were bought from the sellers and was collected in raps of aluminum foil. It was then taken to the laboratory for analysis. The sample was homogenized then pipette using 5ml sterile pipette and test tube. The dilution were then cultured on different media, MacConkey agar, Nutrient agar and blood agar then incubated at 370C for 24 hours. Discrete bacteria colonies were observed and each colony was gram-stained and examined microscopically. Biochemical test were carried out to confirm the particular bacteria present. Bacteria isolated were Staphylococcus aureus 32.4%, Bacillus subtilis 51.9%, and Escherichia coli 15.6%. This microorganisms isolated from contaminated suya meat are capable of causing illness. For instance Staphylococcu aureus produce air exo-toxin and can withstand temperature of 1000C for 30 minutes, when ingested, it causes intoxication manifesting in 4 – 5 hours with acute diarrhea, vomiting and gastroenteritis lasting 6 – 8 hours.
1.1 BACKGROUND OF THE STUDY
Meat is the flesh of animals which serves as food, it is obtained from sheep, cattle, goat and swine (Haman, 2002) meat is a major sources of protein and an important source of vitamins for most people in many parts of the world, thus they are essential for the growth, repair and maintenance of body cells which is necessary for our every day activities.
Meat could be traced back to human history, when primitive men use raw flesh of dead animals. But as man develop, he domesticated wild animals. Beef have been the major supply of meat in Nigeria as a result of extensive and semi-intensive cattle production system in Nigeria by Fulani and Hausa people of the northern Nigeria (Umoh, 2004).
Suya meat is a boneless lean meat of mutton, beef, goat or chicken meat staked on sticks, coated with sauces, oiled and then roasted over wood using fire from charcoal. It is a traditionally processed meat product and is usually not done with strict hygiene condition because they are still done locally. This is served hot and sold along streets, at clubs, picnics centers, and restaurants and within institutions. Suya meat is one of the intermediate moisture products that are easy to prepare and highly relished.
Due to the chemical composition and characteristics, meat are highly perishable foods which provide an excellent medium for growth of many hazardous microorganisms that can cause infection in human and also lead to meat spoilage and economic loss. The most important bacterial meat spoilage is caused by lactic acid bacterial which is physiologically related group of fastidious and ubiquitous gram-positive organisms. These include many species such as lactobacillus, leuconostoc, pediococcus and streptococcus. Since meat has a high nutritive valve, microorganisms could easily grow on it. The possible sources of contamination are through slaughtering of sick animals, washing the meat with dirty water, handling by butchers, contamination by flies, processing close to sewage or refuse dumps environment, spices, transportation and use of contaminated equipment such as knife and other utensils (Igyor and Uma, 2005).
The slaughtering process affords extensive contamination of sterile tissue with gram-negative enteric bacteria from animal intestine including salmonella species and Escherichia coli as well as contaminant such as gram – positive lactic cocci associated with humans, animals and the environment. Enterococci and clostridia have been isolated from lymph node of red animals (Lawries, 2006).
Microorganisms grow on meat causing visual, textural and organoleptic changes when they release metabolite they includes Salmonella typhi, Staphylococcus aureus, Clostridium botulinum, Clostridium perfringens, Bacillus cereus, Streptococcus pyogenes. (John et al, 2001).
The microbial load in meat and meat product increases as long as growth conditions are favourable. The factor influencing microbial growth includes acidity, pH, temperature, water activity, Gaseous requirement, nutrient and competition of microbes for the nutrient. Controlling these factors implies maintaining long shelf