SCALDING, PRECOOKING, AND CHILLING 13 
ing the scalding process; and of various other factors concerned in 
the preliminary treatment of peas were made upon this raw material. 
The results will be discussed briefly in turn. 
RELATION OF WASHING AND SCALDING TO THE WEIGHT OF PEAS. 
Freshly shelled peas, after washing and draining, showed an in- 
crease in weight of about 6 per cent. After scalding for 4 minutes 
and draining for 3 minutes, these peas lost 3 to 4 per cent of their 
original weight; and when they were chilled in cold water for 30 
seconds after scalding, they showed an increase of about 7 per cent 
over their original weight. 
SHRINKAGE OF PEAS. 
The amount of shrinkage in peas varies with the degree of 
maturity, the young tender peas showing more and the mature 
ones much less reduction in bulk. The quantity of peas available 
was not sufficient to determine shrinkage in the various grades, 
and the figures obtained were on mixed peas. Most of them were 
full but not hard; that is, in prime condition for the table. The 
loss in bulk as a result of scalding was determined by measuring 
into No. 2 tin cans, both before and after the scalding treatment. 
Lots aggregating approximately 20 kilograms in weight after 
being scalded 4 minutes in boiling water, showed a loss in bulk 
of from 10 to 14 per cent. Peas of the same picking when scalded 
for 8 minutes in boiling water lost approximately 15 per cent of 
their bulk, showing that the greatest amount of shrinkage takes 
place in the first 4 minutes of treatment. When heated with steam 
for 4 minutes, peas of the same age and kind showed a loss in bulk 
of 6 to 9 per cent. 
When placed in cold water for a short time after scalding, these 
peas regained their original volume. This taking up of water is 
of practical importance, and especially when canning in tin, 
because overfilling, with the undesirable attendant conditions of 
cloudy liquor and the swelling of cans, may easily result unless 
great care is exercised. With older peas, the taking up of water 
was greater, and resulted in an actual increase over the original 
volume of the peas. 
Bitting (9) has noted an actual increase in size in peas follow- 
ing a 10-minute scalding. According to this writer, 28 per cent 
of even the " petit pois " of grade 1 showed an increase in size, and 
82 per cent of grade 3. The results were due doubtless to the 
swelling of starch in the peas, as the increase was less marked 
when the scalding period was shorter. 
Chilling in cold water, therefore, does not cause further shrinkage, 
as is sometimes stated in the literature, at least in the case of peas. 
LOSSES IN SCALDING PEAS. 
The losses resulting when peas are scalded varies with the age of 
the peas, proportion of peas to scalding liquor, vigorousness of 
boiling, and length of the scalding period. Where chemicals are 
used in the water, these may also have an influence upon the amount 
of substances lost. In the present experiments, the losses of the 
various constituents were considerable. 
