Enzymic processing of vegetable protein foods.

Defatted sesame and peanut meals,
and four kinds of beans—chickpea,
green gram, black gram and field bean—
were tested as raw materials for extracting
protein after enzymic hydrolysis.
Conditions required for enzymatic
digestion have been standardized. A
10% suspension is most suitable for
cooking the material, which has been
found to be a prerequisite for enzyme
attack. Sesame meal requires 15 min
steaming, while chickpea has to be
cooked for 20 min. Acid and salt
solutions were tested as dispersion
media to obtain optimum pH, and it
was found that adjusting the pH to
3.0 by dilute acid, after cooking, was
the most suitable treatment.
Sesame meal requires enzyme at
0.25% concentration while 0.15% is
enough for chickpea. Hydrolysis is
completed within 5 hr at 45°C. Of
the commercial proteases tested the
one obtained from Trametes sanguina
was the best for hydrolyzing sesame
meal and chickpea. The products obtained
by enzyme digestion are comparable
to predigested foods prepared
from soybeans, in their chemical composition.
Enzymic hydrolysis increases the
soluble protein content of sesame meal
from 7.21 to 64.14% and that of
chickpea from 16.68 to 86.12%. Lyophilized
hydrolysates of sesame, chickpea
and blend of these two contain
more than 60, 28 and 42% protein respectively.
By suitable blending of
these materials, a protein rich food
with reasonably well-balanced amino
acid composition can be prepared.