RESUMO
BACKGROUND: Nuts are one of the main consumed snacks worldwide and also have an important role among Iranian's food habits. Natural contamination of nuts with aflatoxin is unavoidable and causes a special challenge for nuts safety and quality. OBJECTIVES: The purpose of this research was to study the aflatoxin contamination in commercially-available nuts (pistachio, walnut and peanut) in the markets of Tabriz, Iran. MATERIALS AND METHODS: Sixty two samples of 50 g salt-roasted peanuts and pistachios and 109 samples of 50 g pure pistachios, walnuts and peanuts were collected from different areas of local markets. After the initial preparations, ELISA test was performed for Aflatoxin measurement. RESULTS: Result showed that walnut (90%) and pure pistachio (2.3%) were the most and least contaminated samples, respectively. Mean aflatoxin contamination in the salt-roasted samples (19.88 ± 19.41 µg/kg) was significantly higher than the pure ones (6.51 ± 9.4 µg/kg) (P < 0.001). Respectively, 58.6%, 48.4% and 47.6% of salt-roasted pistachios, salt-roasted peanuts and walnut samples had aflatoxin contamination, which were more than the maximum tolerated level of Iran (MTL, 15 ppb). CONCLUSIONS: It was concluded that aflatoxin content of nuts should be monitored regularly to minimize the risk of aflatoxin hazard and ensure the food safety and quality.
RESUMO
BACKGROUND: Nuts are one of the main consumed snacks worldwide and a significant component of Iranian's diet. Natural contamination of nuts with fungus is unavoidable and is a major challenge to nuts safety and quality. OBJECTIVES: The purpose of this research was to study fungal contamination in commercially available nuts (pistachios, walnuts and peanuts) in the markets of Tabriz, Iran. MATERIALS AND METHODS: 100 samples of 50 gr roasted with salt peanuts and pistachios and 300 samples of 50 gr pure pistachios, walnuts and peanuts were collected from different areas of the local markets. After initial preparation, the samples were cultured on Sabouraud's dextrose agar (SDA). 19 fungal isolates were identified. RESULTS: The results show that Aspergillus niger was the predominant mold among pure (44%) and roasted with salt (14%) nuts (P < 0/001). In addition, percentage of mycotoxigenic fungal contamination was 18% for roasted with salt nuts and 11% for pure samples. CONCLUSIONS: The overall results of the analysed samples showed that the rate of fungal contamination in pure samples was higher than roasted with salt ones (P < 0.005). Results of the current survey could be useful for minimizing fungal contamination and can educate people about the dangers of mold in nuts.
