Survey of mycotoxigenic fungi and mycotoxins on italian rice used for baby foods during storage

Italy is the main rice producer in Europe covering about 50% of the European production. Depending on climate registered during the growing season and on environmental conditions during storage, mycotoxins contamination of rice may result higher than fixed levels by European Commission (Regulaments CE 1881/2006, UE 165/2010, UE 488/2014 and UE 1006/2015). In particular, for aflatoxin B1 (AFB1) and deossinivalenol (DON), maximum amounts admitted are very low in rice (0,1 µg/kg and 200 µg/kg, respectively) becoming even more severe for rice destined to baby-foods. Since few data on contamination of Italian rice are available, a study was planned taking into account 2 different storage methods (traditional warehouse and refrigerated silos) and 6 different rice varieties. Samples were collected at the beginning and at the end of the storage period and, when possible, every 3 weeks for a maximum of 4 months. Samples were analysed for fungal incidence, with particular attention to Fusarium spp. and Aspergillus spp. and for AFB1, DON and sterigmatocystin (STC), a mycotoxin recently signalled in rice, using, respectively, HPLC-FLD, GC-MS and LC-MS/MS. Fusarium spp. were the most represented fungal species found in rice (incidence from 2 to 43%) but also Aspergillus spp. were found in several samples, in particular A. section Flavi (found in 1 variety), A. section Nigri (found in 2 varieties) and A. versicolor (found in all varieties sampled). Mycotoxins tested resulted always below legal limits, but a direct correlation occurs between DON and Fusarium spp. incidence and between STC and A. versicolor incidence.