Effects of different temperatures and durations of heating on the reduction of Ochratoxin A in bread samples

Document Type : Original Article


1 Department of Microbiology, Islamic Azad University, Tonekabon Branch, Tonekabon, Iran

2 Department of Microbiology, Islamic Azad University, Babol Branch, Babol, Iran


Ochratoxin A (OTA) is a mycotoxin produced in corn, rice, and flour. It is a major concern for animal and human health. The purpose of this study was the evaluation of OTA contamination in bread samples gathered from bakeries, in different temperatures and durations of heating. In this study, 32 samples (4 samples of flour and 28 samples of bread) were randomly collected from different bakeries in Babol city, Mazandaran province, Iran, in fall 2013. The OTA content of the samples was measured in different temperatures and durations of heating using competitive direct enzyme-linked immunosorbent assay (CD-ELISA) method. Nonparametric Kruskal-Wallis was applied for data analysis. Results proved that reduction in the amount of OTA in samples during the heating process was significant and longer duration of heating was more effective, than raising the temperature, on OTA reduction. The highest percentage of OTA reduction occurred in constant temperature and when 2 minutes were added to the original time of heating. The lowest reduction rate of this toxin was observed in constant temperature and when 4 minutes was deducted from the original time in each bakery. Our study showed that bread and flour samples do in fact contain OTA, but this toxin is being reduced through heating. Since bread is the most consumed food in the world and also Iran, determination, management, and reduction of OTA in bread should be considered seriously. 


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