Effect of Clove (Syzygium aromaticum) spice as microbial inhibitor of resistant bacteria and Organoleptic Quality of meat

For centuries, spices have been utilized as flavourants, colourants and as preservatives in food. Moreover, spices possess various antimicrobial properties with massive health benefits for the treatment and management of ailments and diseases. The present study was focused on three (3) aspects; (1) isolation and molecular identification of bacteria from the meat; (2) to determine the antimicrobial activity of the spices against the pathogens; (3) to assess the organoleptic properties of the spiced meat. A total of twelve (n = 12) spices evaluated against forty (n = 40) spoilage food-borne pathogenic bacteria (Escherichia coli and Enterococci spp.). The spice extracts were tested using disk diffusion method to determine the inhibition abilities. The results show that clove and black seed cumin extract exhibited excellent antibacterial activity against most pathogenic bacteria. Clove displayed the highest inhibition zone of 18 mm against E. coli (EcFwS1). Clove extract was the most inhibitor followed by black cumin, whereas extracts of thyme and cinnamon showed weak antibacterial activities against the tested strains. The most sensitive strain to spice extracts was Enterococcus spp. (EnFmL1) and the most resistant strain being E. coli. (EcFmS1 and EcFpL1). Untreated meat showed that E. coli and Enterococcus spp. count was 4.4 * 10⁵ ± 3.4 * 10⁵ and 2.2 * 10⁵ ± 3.6 * 10⁴ cfu/mL respectively after 7 days while the single dose of clove showed 5.4 * 10⁴ ± 4.4 * 10² cfu/mL of E. coli and 1.7 * 10⁵ ± 4.1 * 10⁴ cfu/mL of Enterococcus spp. The organoleptic characteristics such as colour, texture, odour, pH, shape of the single dose of clove on the meat was overall acceptable.