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Changes in [alpha]- and [beta]-amylase activities in African finger millet (Eleusine coracana (L) Gaertener) were followed during germination. Germination on a small scale was performed at 15[degrees]C for 1-10 days and at 20, 25 and 30[degrees]C for 1-8 days. [alpha]- and [beta]-Amylase activities in malt crude extracts of germinated finger millet were evaluated spectrophotometrically using chromogenic methods. The highest [alpha]-amylase activity was exhibited in malt flour of finger millet germinated at 15[degrees]C for 9 days and at 20[degrees]C for 6 days, while the highest [beta]-amylase activity was displayed in the malt flour germinated for 5 days at 30[degrees]C. Thermo-stability of these enzymes in malt extracts was also evaluated. Malt extracts incubated at 40 and 50[degrees]C for up to 4 h retained about 84 and 64% of [alpha]-amylase activities, respectively. There was a substantial decrease in [alpha]-amylase activity to more than 90% when malt extracts were incubated at 70 and 90[degrees]C for 40 and 10min, respectively. [beta]-Amylase was completely inactivated when the crude extract was incubated at 70[degrees]C for only 10 min. At pH 5.4, [alpha]-amylase displayed maximum catalytic activity at around 45[degrees]C. Optimum temperature for [beta]-amylase activity at pH 6.0 was between 50 and 55[degrees]C. Activity staining for [alpha]-amylase was also performed and three bands of activity were found in malt extract, each possibly representing an isozyme of [alpha]-amylase from finger millet.

The flowability of oat bran porridge increases when it is cooked under conditions of a steady increase in temperature in the presence of amylase obtained from malt. The starch granules which gelatinize in the porridge are liquefied during cooking. Using this method, the solid content of the porridge can be increased without increasing its viscosity.