In vitro digestibility studies of cereal flours and starches using purified finger millet (Eleusine coracana, ragi, Indaf-15) amylases

Purified finger millet α-amylases designated as α-1, α-2 and α-3 were evaluated for their efficiency to digest pregelatinized cereal and finger millet flours as well as starches derived from them. Ragi and rice flours were hydrolyzed to the same extent by all the three amylases (∼60%), whereas % hydrolysis in case of wheat and maize flours was found to be around ∼50% (α-1), ∼45% (α-2) and ∼70% (α-3). Cereal starches were hydrolyzed to varied extent [60–65% (α-1), 50–55% (α-2) and 60–70% (α-3)]. Maltotetraose was the major oligosaccharide produced by these enzymes from the aforementioned flours as well as starches after 15 min hydrolysis. Higher oligosaccharides (DP-8 and above) have undergone further degradation after 120 min. α-3 was found to be the most efficient followed by α-1 and α-2 in their hydrolyzing capacity of various cereal starches as well as flours.