Evaluation of aflatoxins B1, B2, G1 and G2 traditional and industrial barley malts in Ethiopia

Abstract

Background: The commonly used ingredient in home-made and conventional beer brewing is the traditional and industrial barley malt. However, this cereal grain is prone to pre-harvest and post-harvest contamination with aflatoxin. Aflatoxins have been shown in many studies to be teratogenic, mutagenic, genotoxic and hepatocarcinogenic to humans and animals.

Objective: This research was conducted to evaluate the presence of aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) in both traditional and industrial barley malts in Ethiopia.

Methods: Samples of 24 traditional barley malts (8 samples from each towns) were collected from Debremarkos, Finoteselam and Enjibarra towns. Six industrial barley samples (3 local and 3 imported) were collected from three breweries. Aflatoxins B1, B2, G1 and G2 were determined by immunoaffinity column clean up and high performance liquid chromatography with fluoresce detection.

Results: The mean aflatoxin level of traditional barley malts from Debremarkos, Finoteselam and Enjibarra towns were 5.30 μg/kg, 1.90 μg/kg and 6.72 μg/kg, respectively. The percentages of barley malt samples contaminated by aflatoxins are 37.5% in both Debremarkos and Finoteselam and 50% in Enjibara. The mean moisture content of the barley malt samples were 6.6%, 9.7% and 7.4% for Debremarkos, Finoteselam and Enjibara, respectively. Mean aflatoxin content of traditional malts from Debremarkos and Enjibara exceed the regulation of the European Commission. The aflatoxin content of imported malts exceeds those of industrially produced local malts. The aflatoxin content of industrially produced local malts are below the permitted limits of EU regulation in contrast to imported malts. In conclusion, the present study provides information about the occurrence of aflatoxins in traditional and industrial barley malts. The results of the study revealed that, consumption of both home-made and conventional beer may pose a risk of aflatoxin exposure.