SCALDING, PRECOOKING, AND CHILLING 5 
Carefully weighed lots were washed thoroughly in cold running 
water, drained, and weighed again. This showed the increase in 
weight resulting from the washing process. To obtain a base line 
for comparison in the determination of the amount of shrinkage re- 
sulting from the scalding process, weighed quantities of the spinach 
without washing or other treatment were packed firmly into> No. 2 
open-top tin cans and the yield in cans of material noted. These 
findings were later compared with yields obtained similarly from 
the material subjected to the various methods of treatment. 
Lots weighing 1,700 grams, after thorough washing, were packed 
tightly into tin cans and glass jars without other preliminary treat- 
ment. In the case of the tin cans, hot water was placed in the can, 
the freshly washed spinach packed in as tightly as possible by dis- 
placement of water, and the cans sealed immediately. In the case 
of the glass jars, a small quantity of water only was added to the 
jar after the spinach was packed in. The test cans and jars were then 
processed, part by the intermittent treatment in boiling water for 1 
hour on each of 3 successive days, part by boiling continuously 
for 3 hours or more in the water bath, and another part by the appli- 
cation of steam under pressure at 116° C. for 1 hour 1 in the auto- 
clave. These furnished information upon the quality of the un- 
treated spinach as compared with the scalded material. 
Lots weighing 1,700 grams were plunged into 16,000 cubic centi- 
meters of boiling distilled water for 2 minutes, drained, weighed 
again, placed in cans and jars as before, the yield in cans recorded, 
the cans sealed, and then processed as before. Samples of the raw 
material, scalded material, and scalding water were taken and sub- 
jected to chemical analysis. 
The same procedure was followed with other 1,700-gram lots, ex- 
cept that the scalding period was increased to 4 minutes. These tests 
made possible an observation of the effect of scalding upon the ap- 
pearance and quality of the product and a determination of the losses 
caused by the treatment. 
The effect of plunging the freshly scalded spinach into cold 
water immediately after scalding was determined upon other 
samples handled as just described by draining for 30 seconds after 
scalding, chilling in cold water for 30 seconds, draining, and then 
canning. Here, also, samples for chemical analysis both of the 
spinach and of the scalding and chilling waters were taken at the 
various stages of the process. The canned product from these tests 
was used for comparison with the material from the various other 
tests. 
In addition to the scalding tests using distilled water, other 
experiments of a similar character were performed using boiling 
2 per cent brine, 0.1 per cent sodium bicarbonate, and 1 per cent 
citric- acid solutions. 
Since scalding in live steam, instead of in boiling water, has 
been quite widely recommended for vegetable greens (see refer- 
ences, p. 8) because of the saving in nutrients lost in the boiling- 
water treatment, tests were carried out in this work to throw 
further light upon the merits of this method. The effect of steam 
upon the physical properties of the spinach, and the table qualities 
of the product, received special consideration. 
