Microbiological quality of industrial and artisanal pasta from italian market

Abstract

The aim of this study was to evaluate the microbiological quality of fresh and dried pasta products, both industrial and handicraft. A total of 85 different samples (5 aliquots per sample) were collected from retail market. Parameters investigated were enumeration of total count of aerobic mesophilic bacteria at 30 °C, coliform bacteria, β-glucuronidase-positive Escherichia coli, presumptive Bacillus cereus, coagulase-positive Staphylococci, Moulds, Listeria monocytogenes and the detection of Salmonella spp. None of the samples tested contained Salmonella spp. and Listeria monocytogenes. Dried pasta showed generally an excellent hygienic-sanitary profile. Among fresh pasta the share of compliant samples, according to local regulation, was 78.8%. Not packed fresh pasta was more contaminated and in particular if stuffed. Moreover, presumptive Bacillus cereus was present in almost 50% of the samples examined, confirming the importance of introducing the research of this microorganism in official control plans. A water activity greater than 0.92, the processing steps and some ingredients used (in particular ricotta cheese) may increase bacterial growth by limiting the health and the shelf-life of this products. This study suggests that presumptive Bacillus cereus can be considered an indicator of process hygiene with different characteristics respect to coagulase-positive Staphylococci, because it appear more oriented to reveal problems with ingredients present in filling (almost cheese) from both industrial and artisanal production.