Listeria monocytogenes in ham sliced in supermarkets in Recife city, Pernambuco state

Abstract

The aim of this study was to investigate Listeria monocytogenes in ham sliced in supermarkets in Recife city, Pernambuco state. In total, 40 samples of sliced ham were collected, and 25 g of ham was added to 225 mL of Demi Fraser broth. After incubation, 0.1 mL was inoculated in Fraser broth and, subsequently, sown in supplemented Listeria Selective Agar, based on Otaviani and Agosti. The following tests were carried out for confirmation purposes: Gram stain, motility test, catalase test and cAMP test. There was L. monocytogenes in 25% (10/40) of the samples. The presence of L. monocytogenes in ready-to-eat food, such as sliced ham, is likely related to lack of proper equipment-cleaning in supermarkets, a fact that poses great risk to public health.