Effects of some processing methods on the toxic components of African breadfruit (Treculia africana)

A variety of breadfruit (Var africana) was evaluated for the presence of some anti-nutrients. It was found to contain some hydrogen cyanide (26.45 mg/kg), tannin (184.10 mg/g), starchyose (1.8%) and rafffinose (1.01%). Different methods of processing such as fermentation, boiling, autoclaving and germination was found to have effect on the anti-nutritional factors. Fermentation for 48 h reduced hydrogen cyanide activity to 0.01 mg/kg, tannin to 6.42 mg/g, haemagglutinin to 6.80 Hu/g, phytate to 0.80 mg/g, starchyose and raffinose to 0.32% and 0.01%, respectively. Boiling for 120 min reduced hydrogen cyanide activity to 4.40 mg/kg, tannin to 6.2 mg/g, haemagglutinin to 3.6 Hu/g, phytate to 0.56 mg/g, starchyose and raffinose to 0.44% and 0.02%, resppectively, while autoclaving for 60 min markedly reduced HCN to 3.40 mg/kg, tannin to 4.42 mg/g, haemagglutininin to undetectable, phytate to 0.42 mg/g, starchyose in traces and raffinose to undetectable. Finally, germination for 120 h reduced the HCN to 4.68 mg/kg, tannin to 18.16 mg/g, haemagglutininin to 10.0 Hu/g, phytate to 0.78 mg/g, starchyose to 0.24% and raffinose to 0.01%. From this research work, any of the processes could be employed in detoxifying the anti-nutritional factors in breadfruit. However, autoclaving was found to be best in the elimination of haemagglutinin, starchyose and raffinose while fermentation was effective in the reduction of hydrogen cyanide.