بررسی مقایسه اثرات خشک کردن آفتابی و خشک کردن دستگاهی در کاهش آلودگی دانه های پسته به اسپور قارچهای مولد آفلاتوکسین

‭Aflatoxins are produced by certain strains of Aspergillus flavus and Aspergillus parasiticlls. Being ubiquitous the potential of these fungi to contaminate food stuffs and animal feeds is widespread. The occurrence and magnitude of aflatoxin contamination varies according to geographical and seasonal factors, and also with the conditions under which a crop is grown, harvested and stored. In the last decade, many producers used sunlight for drying pistachio after harvesting and pealing them. According to them, compared to mechanical drying, sun drying induces very little change in taste and quality of pistachio. This study evaluates sun drying pistachio method, from the view point of spore density of aflatoxin producing fungus, and compares it to mechanical drying. A group of pistachios from different pistachio processing lines were taken and spread in the sun fie1d for drying. Then Samples were selected from all around the sun field at 8-hour interva1s until 48 hours. In the mechanical dryer, sampling was done at 4‬ص‭hour intervals until 24 hours. Spore density of all the samples was evaluated in the laboratory using AFP A media culture. Results indicated that different areas of sampling had different contamination as different spore density was observed in different samples. Another important finding was the period of exposure of pistachio in the sun field. The spore density decreased with longer exposure in sun field. Same results were found in the samples fropl the mechanical dryer too, leading to the conclusion that decrease in the moisture content in pistachio caused the spore density to decrease.‬