100. Ochratoxigenic moulds in the air of a salami ripening room in Pavia Oltrepò

Ochratoxin A (OTA) is a mycotoxin synthesized by several Aspergillus and Penicillium species when certain condition of temperature, humidity and pH occur. Mycotoxins are produced and released in cereals and vegetal foodstuffs but also in fermented meat products. Traditional salami are colonized by fungi present in the air of ripening room, because no fungal starter is usually added. Even if moulds play an important role in the correct ripening of fermented meat, the presence of OTA proved to be nephrotoxic, carcinogenic, teratogenic and immunotoxic (1) has to be monitored. This work is part of a project funded by Ministry of Health aimed to search for ochratoxin A and ochratoxigenic moulds presence in salami manufactured in Lombardy and Emilia Romagna. Since in Pavia Oltrepo’ were found Aspergillus westerdijkiae, a strong OTA-producer and the OTA above law’s limits (1µg/kg of meat) (2) in two salami manufactured from the same producer in two different periods of 2014, we have sampled the air and the surfaces of this family-run factory to identify the source of contamination. Quantitative air sampling was conducted with SAS Super ISO 100 using PDA medium (Potato Dextrose Agar). The air volumes aspirated were 200 and 100 liters in each ripening room and 200 liters in the other environments (the laboratory, the bakery and the outdoor environment). For the qualitative analysis, the same medium was used. For surface sampling five swabs from different points of the ripening rooms and two from salami belonging to different batch produced in 2015 were collected. Fungal loads were evaluated on PDA and DRBC (Dichloran Rose Bengala Cloramphenicol Agar) media after 5 days at 25 °C incubation (3). Moulds identification was performed observing macroscopic and microscopic features as suggested by dichotomic keys for Aspergillus and Penicillium species (4,5). All fungal loads resulted high and A. westerdijkiae was the predominant species in all rooms, except for the outdoor environment in which it was anyway found. As regarding the surfaces, A. westerdijkiae was isolated from 4/5 points of the ripening rooms and from both the salami produced in 2015. This massive contamination of ochratoxigenic strains is very dangerous because it was proved that these strains are able to produce ochratoxin A, 691 µg/kg and 9,4 µg/kg respectively in two salami manufactured in 2014. For this reason is crucial to sanitize all rooms and implement the strategies to prevent this kind of contamination or at least ochratoxin A synthesis.