52 
to give the proportion of corn to liquor of 4to 1. 
es over steam with constant eee 
PRESSURE IN POUNDS PER SQUARE INCH 
Fie. 
No. 2 tin cans, sealed at different uniform temperatures © 
pansion of the air of the head space. 
(QVe= accint © 
ieee ae 
Vf oa 
aes IN MINUTES 
20.—Experimental time-pressure curves for corn in 
and processed for 2 hours at 100°, 116°, and 121° C. 
Prepared ‘“‘ Maine style’’; 550 grams of material used. 
Proportion of corn to liquor, 4:1. Curve for corn: A, 
Precooked at 100° C., sealed at 244° C., and processed at 
100° C.; a, precooked to 100° C., sealed at 244° C., and 
processed at 116° C.; a’, precooked to 100° C., sealed at 
244° C., and processed at 121° C.; B, precooked to 80° 
C., sealed-at 70° C., and processed at 100° C.; 06, pre- 
cooked to 80° C., sealed at 70° C.,-and processed at 
116° C.; 6b’, precocked tc 80° C., sealed at 70° C., and 
processed at 121° C.; U, precooked to 80° C., sealed at 
80° C., and processed at 100° C.; ¢, precooked to 80° 
C., sealed at 80° C., and processed at 116°-£.; ec’, pre 
cooked to 80° C., sealed at 80° C., and processed at 121° 
C.; X, with no precooking, sealed at 20° C., and proc- 
essed at 100° C.; z, with no precooking, sealed at 243° 
C., and processed at 116° C.; 2’, with no precooking, 
sealed at 244° C., and processed at 121° C. © 
BULLETIN 1022, U. S. DEPARFMENT OF AGRICULTURE. 
The corn was then 
until the temperature 
reached 80° 
was then weighed into 
the No. 2 test cans, 
550 grams being used 
in each case, brought 
to the desired uni- 
form temperatures, 
sealed, the tests im- 
mediately begun, and 
the time-pressure 
curves determined. 
This procedure held 
for those cans sealed 
at. (O° sand S0raee: 
The procedure was 
the same with the 
cans sealed at 20° to 
244° C., except that 
in one set of experi- 
ments the corn was 
precooked to 100° and 
in the other the corn 
was placed in the test 
cans without any pre- 
cooking at all. Proc- 
essing in all cases was 
for 120 minutes or 
thereabouts at the re- 
tort. temperatures of 
10025 AG and, cio 
C., respectively. Fig- 
ure 20 shows the 
curves obtained in 
these tests. 
These curves dem- 
onstrate the following 
facts: 
(1) The pressure rises 
almost immediately to 
a high point when the 
steam is turned on, as a 
result of the sudden ex- 
After the first minute the rise is more grad- 
ual, the rate corresponding largely to the rate of temperature change in the corn. 
(2) Relatively low pressures are obtained when the higher sealing temper- 
atures are employed. 
Ges 
ee ee 
