SCALDING, PKECOOKING, AND CHILLING 27 
TOMATOES. 
Because of its delicate structure and highly perishable nature, the 
preliminary treatment of the tomato preparatory to canning is a 
matter requiring careful attention. In no branch of canning is the 
exercise of good judgment more important. 
Scalding, when properly done, is the best method known to facil- 
itate the efficient and economical removal of the peel — but the scald- 
ing treatment must be under careful control or considerable losses 
are likely to occur and the quality of the product may be seriously 
affected. The need is to loosen the skin quickly and effectively, with- 
out too much softening of the pulp. 
The tissues of the tomato collapse very rapidly when exposed to 
high temperatures, and along with this collapse goes loss of juices. 
Furthermore, if the scalding is too prolonged, the entire pulp softens, 
the tomato becomes mushy, and it is impossible to make an attractive 
and satisfactory pack. When scalding is properly done the skin is 
loosened, but the underlying pulp is not seriously affected. 
In a commercial cannery, the skin is loosened by either steam or a 
boiling- water bath. In home canning only the latter is feasible, be- 
cause scalding with steam requires an abundant supply of steam, and 
this under some pressure. The entire surface of the tomato must be 
subjected to the scalding medium instantaneously, and steaming in a 
boiler or colander over a kettle of boiling water, as is sometimes 
done with certain vegetables in the home, would heat and soften the 
pulp too much. If steam is used, there must be a vigorously flowing 
supply of it, it must be applied by means of properly arranged jets, 
and its application must be brief — just long enough to loosen the 
skin. The same applies to scalding in water. The best results can 
be obtained only when the water is boiling vigorously ; otherwise, the 
tomatoes will be too much softened, and the losses will be entirely 
too great. 
With tomatoes fully ripe but not soft, about 30 seconds' treatment 
with steam or boiling water is sufficient; but the person doing the 
scalding must be allowed a little latitude in order that the scalding 
may be suited to the particular tomatoes in hand. The rule should 
be, however, the shortest possible scalding that will sufficiently loosen 
the skins. 
Immediately after scalding, the tomatoes should be either sprayed 
with cold water or plunged into a vessel or vat of clean cold water. 
The purpose of this is to check the softening, and to facilitate 
handling without waste. 
Comparison of canned tomatoes peeled without scalding with 
others peeled after scalding and chilling in the usual way showed 
that these operations did not in any way improve the color or 
flavor of the finished product. The function of scalding and chill- 
ing in the handling of tomatoes is to make possible the economical 
removal of the skin. 
Some form of preheating before sealing is necessary to get a good 
fill in the cans and jars, to prevent undue strain on tin cans during 
processing, and to assure good vacuum in the cans after cooling. 
