Microbial Analysis and Assessment of Heavy Metals of Selected Fresh Meat Samples in Kontagora Local Government Area of Niger State, Nigeria

Abstract

This study assessed and analysed microbes and heavy metals in fresh raw meat (heart, stripes, liver and kidney) of cow, goat and ram from abattoirs and retail stalls in Kawo and Kontagora, Niger State, to ensure safety and quality of meat products. Meat, a good source of basic nutrients needed by the body, is influenced by the level of its nutritive value, pH, water, temperature, storage and processing methods, which predispose it to microorganism’s growth and heavy metals presence. Parts of beef, chevon and mutton (n = 48) were randomly selected and collected at every visitation, into sterile polythene bags with ice packs and transported to the laboratory for microbiological and heavy metals analyses. Micro-organisms analyses were carried out using nutritive MacConkey, Mannitol salt, Salmonella–Shigella (SS) and Potato dextrose agar as standard procedures for enumeration and identification. Laboratory quality control procedures were ensured. The total viable counts of meat samples showed microbial contamination. The overall mean microbial load (TBC) was between 36.0 – 42.5 x 10 2 cfu/g and 14.25 – 15.5 x 102 cfu/g for meat sampled in Kawo and Kontagora respectively. TCC was at 6.5 – 16.25 x 102 cfu/g in Kawo and 2.0 – 7.0 x 102 cfu/g in Kontagora. The TBC in sampled meat from Kawo was significantly higher than Kontagora. A total of 12 isolates belonging to 8 genera were identified, including Staphylococcus aureus, which was dominant in both locations (18.51 %). Salmonella typhi isolate was similar (3.7 %) for both locations. The meat parts studied revealed the presence of all the heavy metals examined in the range 0.00 – 120.96 mg/kg irrespective of sampling location and meat parts. Zn in cow heart and tripe, Cu in cow tripe and Mn in all the cow parts were below detection while Fe recorded the highest concentrations (84.11 – 120.96 mg/kg), followed by Mn (0.00 – 1.70 mg/kg) in all meat samples. Pb, Cd, Zn, Cu, Cr and Ni recorded values < 1.00 mg/kg. All meat samples showed microbial contamination within the satisfactory and borderline levels as well as heavy metals levels below the recommended allowable limits set by the standard organisations. Among others, it is recommended that abattoir practices and meats from retail stalls should be regularly monitored to ameliorate meat safety for public consumption.