Assessment of aflatoxin B1 and ochratoxin A levels in sorghum malts and beer in Ouagadougou

Abstract

Mycotoxins are natural metabolites produced by fungi that can cause disease and death in human and animals alike, even in low concentrations. More than thirty mycotoxins that contaminate sorghum (Sorghum bicolor L.) and its derived products are known. This work aimed to investigate the presence of aflatoxin B1 and ochratoxin A in sorghum malt and beer, sampled between January and April 2012 in Ouagadougou. Mycotoxins in fifty samples of sorghum beer and twenty samples of sorghum malts have been purified using immunoaffinity columns, and later identified and quantified using high performance liquid chromatography (HPLC). Aflatoxin B1 and ochratoxin A were no found in any of the sorghum beer samples. However, 25% of the sorghum malt samples contained aflatoxin B1 with an average of 97.6 ± 88.2 ppb (p < 0.05), while none contained ochratoxin A above the level of 0.8 ppb (ochratoxin A limit of detection). From the samples collected in this study, consumption of sorghum beer seems to be safe concerning contamination in aflatoxin B1 and ochratoxin A but a dietary assessment of exposure should be conducted.   Key words: Aflatoxin B1, ochratoxin A, sorghum beer, sorghum malt, HPLC.