بررسی آفلاتوکسین و قارچ های مولد آن در فندق استان گیلان

Approximately 2 00 hectares of hazelnut trees were grown in Guilan province in the North of Iran. Aflatoxin contamination of exported Turkish hazelnut to Europe and USA has remained as an important problem. Aflatoxins are the secondary metabolites which produced mainly by Aspergillus flavus and A. parasiticus. This work was conducted to clear the contamination risk of aflatoxin and aflatoxin producing fungi in the hazelnut produced in Iran and mainly consumed internally. In this research project during two consequences years aflatoxin producing - Aspergillus species were monitored in hazelnut samples collected from Eshkevarat and Deilaman dry land areas in Guilan province at harvest time, after two months storing at local storages and after processing at the local processing sites. The samples were included of 20- 33 samples collected from hazelnut trees at harvest time, five to ten samples from local storages and five samples after processing stages for each year. To study the fungal contaminations, 100 shells and kernels hazelnut pieces of each sample plated on PDA and AFPA artificial media separately followed by surface disinfection with 0.5% Sodium Hypochlorite and incubated at 28C؛ for 10 days. Aflatoxin contaminations of the samples were estimated using reversed-phase high performance liquid chromatography (HPLC) + IAC. In spite of the high occurrence frequency of aflatoxin producing fungi (45%), the contamination level of aflatoxin producing fungi and afltoxins were low (1-1.7% and 0.1- 0.4 ppb respectively) in hazelnuts samples collected at harvest time samples. The population density of Aspergillus flavus and A. parasiticus increased to 2.9% in hazelnut samples after 3 months of storing at local storages but due to closing the shells aflatoxin contamination was not occurred and aflatoxins were not found in the storages samples. High levels of aflatoxins (54ng/g) were determined and Aspergillus flavus and A. parasiticus were found more frequently (55%) after processing stages. Based on the results obtained from this project it is recommended that the traditional stores must be improved using HACCP principals.