Hydrolysis of raffinose and stachyose in cowpea (Vigna unguiculata) flour, using α-galactosidase fromAspergillus niger.

Filamentous fungi, isolated from the enriched surface of garden soil, were screened for α-galactosidase production after growing on wheat-bran/carbohydrate substrate. One isolate,Aspergillus niger, had the highest enzyme activity (5.1×10(-2) units/mg protein) at pH 5.0 and 50°C. Treatment of cowpea flour with the crude enzyme reduced the raffinose and stachyose content by 95% and 82% respectively. This technique could therefore be useful in controlling the flatulence activity of cowpeas.