Aspergillus and Penicillium toxins in chestnuts and derived products produced in Italy

Occurrence of aflatoxins, ochratoxin A, sterigmatocystin, cyclopiazonic acid, citrinin, roquefortine C and mycophenolic acid in fresh chestnuts and dried chestnut products was surveyed. A total of eighty-two samples were collected from retail outlets located in northern Italy. After specific extraction and purification through immunoaffinity or prepacked columns, mycotoxins were analysed using HPLC-FLD or HPLC-MS/MS. In fresh chestnuts, mycotoxins were rarely detected, while a widespread contamination was found in dried products, particularly in chestnut flour. The incidence of aflatoxin B-1 was 92.0 and 40.0% in chestnut flour (maximum value 58.6 mu g kg(-1)) and dried chestnuts, respectively; in chestnut flour, the percentage of samples exceeding the value of 2.0 mu g kg(-1) for aflatoxin B-1 (maximum limit fixed by EC Regulation 165/2010 in dried fruits) was 24.0%. Chestnut flour was also often contaminated with ochratoxin A, citrinin, roquefortine C and mycophenolic acid, showing sometimes high values (particularly for mycophenolic acid); in 80% of samples, more than four mycotoxins were detected. To the best of out knowledge, no data are available from previous studies about the occurrence of citrinin, rogue-fortine C and mycophenolic acid in chestnuts and derived products. These results showed that probably the contamination occurred in the post-harvest, during exsiccation, storage and sorting; the high incidence and concentration found in chestnut flour are probably related to the practice of producing it by grinding of the product coming from sieving of dried chestnuts. (C) 2014 Elsevier Ltd. All rights reserved.