PCR-based Quality Control of Listeria spp. and L. monocytogenes in Ready-To-Eat Salads Sold in Italy

Title: PCR-based Quality Control of Listeria spp. and L. monocytogenes in Ready-To-Eat Salads Sold in Italy

Volume: 7 Issue: 1

Author(s): Ari Q. Nabi, Anna Vernile, Giuseppe Spano, Giovanna Lasalandra, Luciano Beneduce, G. Colelli and Salvatore Massa

Affiliation:

Keywords: Minimally processed foods, Listeria monocytogenes, pathogens, PCR technique, food quality, ready to-eat salads (RTE), pathogenic bacteria, mesophilic aerobic, DNA Extraction, PCR Analysis

Abstract: A total of 48 samples of ready to-eat salads (RTE), containing different varieties of salads, of different brands sold in Italy, were purchased from several supermarkets, during period 2008 – 2009. This study was performed to determine whether microbial contamination, and in particular pathogenic bacteria, such as Listeria monocytogenes, were present in these food products. Samples were examined for mesophilic aerobic counts, yeasts and moulds, total and fecal coliforms, and presumptive Listeria monocytogenes counts.

Results showed that, in general, the highest microorganism counts were associated with samples containing grated carrot (6.3 Log cfu g-1 of aerobic mesophilic microorganisms; 4.6 Log cfu g-1 of yeast and moulds; 2.8 Log cfu g-1 of total coliforms), while the lowest counts were, generally, associated with samples containing lettuce (2.8 Log cfu g-1 of aerobic mesophilic microorganisms; 2.3 Log cfu g-1 of yeast and moulds; 2.3 Log cfu g-1 of total coliforms). Of all the samples analyzed, only three (6 %) harboured L. monocytogenes.

Cite this article as:

Q. Nabi Ari, Vernile Anna, Spano Giuseppe, Lasalandra Giovanna, Beneduce Luciano, Colelli G. and Massa Salvatore, PCR-based Quality Control of Listeria spp. and L. monocytogenes in Ready-To-Eat Salads Sold in Italy, Current Nutrition & Food Science 2011; 7 (1) . https://dx.doi.org/10.2174/157340111794941102