Traceability of artisan raw milk cheeses of the Marche region: a preliminary approach

The aim of the study was to distinguish artisan raw milk cheeses (Pecorino, Caciotta, Caprino and Caserotto), which are typically manufactured in the Marche region, from pasteurized milk competitors, available on the market with the same denomination. Raw milk cheeses were collected from four local dairy farms, while pasteurized milk cheeses were picked up at the retail level from supermarkets. All the samples were subjected to: (i) pH and aw measurements; (ii) determination of the main compositional parameters (NaCl, lipids, proteins, rancidity, peroxides); (iii) viable counting of lactobacilli, mesophilic lactococci, thermophilic cocci, total coliforms, Escherichia coli, Staphylococcus aureus, Salmonella spp. and Listeria monocytogenes; (iii) PCRDGGE analysis of the bacterial DNA extracted directly from the food matrices and the bulk cells harvested from the MRS and M17 dilution plates; (iv) solidphase microextraction coupled with gas chromatography (GC‐SPME). Physicochemical and microbiological data were subjected to principal component analysis (PCA). Except for Caserotto, which was characterized by a short ripening period, a high hygienic standard of both the artisan and industrial manufactures was verified. The polyphasic PCR‐DGGE approach, combined with traditional plating methodology, revealed slight differences in the microbial composition of raw and pasteurized milk cheeses, while a neat diversification was highlighted by SPME‐GC. PCA allowed the artisan manufactures to be definitely distinguished from the industrial competitors. Given the increasing importance of food traceability for safety, quality and typicalness issues, the polyphasic approach proposed may represent a suitable tool for tracing traditional dairy specialties, as those considered in the present study.