Effect of UV-C Irradiation on Fatty Acid Profile of Pistachio Kernels and Prevention of Aflatoxin Production

 Pistachio is one of the most crucial exported agricultural products of Iran. Pistachio nut is susceptible to fungal contamination and aflatoxin production.

 This study examined the effect of some functional factors of the optimized rotational UV-C irradiation system on the prevention of aflatoxin production by Aspergillus flavus. The factors included lamp distance from the products (10, 20, and 30 cm), irradiation time (15, 30, and 45 minutes), and the number of UV lamps (3, 5, and 7).

 The best treatment was the lamp distance of 10 cm, 30 minutes of irradiation with three UV-C lamps. The results revealed that aflatoxin levels in the irradiated sample were significantly lower than in the control sample (p<0.05). Also, UV-C irradiation caused significant changes (p<0.05) in some fatty acid profiles, as the amount of linolenic acid in the control sample (0.85±0.07%) was higher than the value in the irradiated sample (0.15±0.07%). However, the values of other fatty acids such as palmitic acid, palmitoleic acid, stearic acid, oleic acid, and linoleic acid were not significantly different between the control and irradiated sample.

 This irradiation system can be installed in different pistachio processing lines to disinfect products, which is very useful in reduction and prevention of the aflatoxins.