Residual cyanogens, chemical composition and aflatoxins in cassava flour from Tanzanian villages

Abstract

Cassava samples processed by wet fermentation, solid-state fermentation and sun-drying were analysed for residual cyanogens and the presence of mycotoxins. Wet fermentation was very effective in reducing cyanogen content in bitter varieties. The total cyanogen content of 5.84 mg HCN kg −1 was less than that for samples processed by solid-state fermentation which had a residual cyanogens content of 14.0 mg HCN kg −1. Sun-dried cassava samples (sweet varieties) had 6.8 mg HCN kg −1. The chemical composition of cassava flour, processed by wet fermentation, solid-state fermentation and sun-drying in Tanzanian villages, was also determined. Wet fermentation resulted in lower contents of vitamin C, reducing sugars and protein and also low pH values compared to samples processed by solid-state fermentation and sun-drying. Solid-state fermented samples had higher reducing sugars and protein contents than sun-dried samples. No mycotoxins (aflatoxins) were detected in the cassava samples.