Effect of Penicillium nalgiovense as protective culture in processing of dry-fermented sausage “salchichón”

In this work the implantation of a protective culture of Penicillium nalgiovense on commercial dry-fermented sausages “salchichón” and its effect over presence of mycotoxin-producing moulds belonging to contamination origin was evaluated. In addition, the suitability of real-time quantitative PCR (qPCR) as a rapid and sensitive method to test implantation of protective culture throughout the “salchichón” processing was also tested. Dry-fermented sausages “salchichón” inoculated with a non-toxigenic protective P. nalgiovense and subjected to three different commercial ripening processes were analysed. At first, ability of P. nalgiovense strain to avoid growth of an ocratoxin A (OTA)-producing strain and its mycotoxin production in a controlled model system was demonstrated. P. nalgiovense was quantified by a qPCR designed on the basis of the ITS region and values higher than 106 ufc/cm2 in both inoculated and non-inoculated “salchichón” were obtained. This technique should be considered a good tool to verify the implantation of protective culture of P. nalgiovense. Producing moulds of aflatoxins, OTA, patulin, sterigmatocystin and verrucosidin and the corresponding mycotoxins were not detected in any dry-fermented sausages tested, including those non-inoculated ones. Thus, presence of P. nalgiovense is inhibiting growth of toxigenic moulds. Utilization of a non-toxigenic fungal protective culture in dry-fermented sausage “salchichón” processing should be considered as a good tool in the preventive programmes to avoid growth of toxigenic moulds.

► Penicillium nalgiovense avoids presence of toxigenic moulds on salchichón. ► OTA is not detected in salchichón with P. nalgiovense as protective culture. ► ITS-based qPCR is a reliable method to monitor growth of P. nalgiovense in salchichón.