SOY AND RELATED FERMENTATIONS. 7 
After being soaked for 20 to 24 hours the swollen beans are cooked 
in an open kettle or under pressure until they are soft enough to be 
easily pressed flat between the thumb and finger. This desired soft- 
ness can be obtained by autoclaving at 15 pounds pressure for 50 
minutes and also by much longer cooking in an open kettle. Auto- 
claving under pressure has the advantage of sterilizing the material. 
A slight excess of water, just more than enough to cover them, is 
added to the beans before autoclaving. The beans are drained as 
soon as the autoclave runs down. 
When the cooking and draining have been completed the beans 
are spread out to cool in about a 1-foot layer on a large traylike plat- 
form, being turned over from time to time to hasten the cooling. Or 
they may be spread in wire trays and cooled with the draft of air 
from an electric fan. The rapid cooling of the hot sterile beans pre- 
vents the growth of organisms collected from utensils and handling 
and further lessens the exposure incident to stirring or turning. 
The wheat is first roasted and then crushed unevenly. The roast- 
ing should be continued until the wheat is crisp but not tough, and 
is browned to produce a slightly charred flavor. It is said that 
some manufacturers of soy sauce roast the wheat only slightly while 
others char the cereal. The browned wheat is believed by the 
Japanese to add flavor to the finished product through the forma- 
tion of maltol due to activity of yeasts during the moromi stage 
of the fermentation. It also adds a desired brown color. In the 
roasting of the wheat practically all microorganisms are killed. If 
the wheat were browned slightly more than was the practice and 
heaped up hot in large quantities, as in shoyu factories of Japan. 
FlG - 4 - — Increase in volume of beans caused by soakim 
number of beans. 
Each pile contains the same 
