CAN ALL FOOD THAT CAN BE CANNED 7 
canning purposes may be used as containers 
for jams, etc. The top-bail should go into 
position with a light snap. If too loose it 
should be taken off and bent slightly inward 
in the center. If too tight bend outward. 
2. Screw-top Jars . — Use only enameled, 
lacquered or vulcanized tops. Screw the top 
on tightly 
without the 
rubber. If the 
tip of a knife 
or finger - nail 
can be inserted 
under the rim, 
the tops should 
not be used for 
cold-pack can- 
ning. If the 
defect is very 
Fig. 9. Wire rack for jars. slight, how- 
ever, it may 
be remedied by pressing a knife handle on 
the lower edge against a hard surface, thus 
straightening the offending bulge. Another 
test is made by putting on the rubber, screw- 
ing the top on tightly and then pulling the 
rubber out. If the rubber returns to place, 
the top does not fit and should not be used 
on that jar. 
3. Vacuum seal jars may be tested in the 
same way as the glass-top jars. See if the tops 
rock if tapped, when placed on the jar without 
fastening. 
STANDARDS AND TESTS FOR RINGS 
1. Good Rubber Essential . — Buy new rub- 
bers every year, as rubbers deteriorate from 
one season to another. A good rubber for 
Fig. 10. Simple test for rubbers. A perfect rubber 
will show no crease or break after being folded tightly 
several times. 
cold-pack canning must be such as to stand 
four hours of continuous boiling or one hour 
under 10 pounds of steam pressure. The 
combination of moist heat plus acids and 
mineral matter in vegetables and fruits tends 
to break down the rubbers during steriliza- 
tion. Rubbers kept in a hot or very warm 
place, as for example, on a shelf near the 
kitchen range, will deteriorate in quality. 
Be very particular about the rubbers used. 
Spoilage of canned goods has been traced 
frequently to the use of poor rubbers. 
‘ 2. Testing Rubbers . — It is always well to 
test rubbers when buying. A good rubber 
will return to its original size when stretched. 
It will not crease when bent double and 
pinched (Fig. 10). It should fit the neck 
of the jar snugly. It is cheaper to discard a 
doubtful rubber than to lose a jar of canned 
goods. 
GRADING 
Vegetables and fruits should be sorted ac- 
cording to color, size and ripeness. This is 
called grading. It insures the best pack and 
uniformity of flavor and texture to the canned 
product, which is always desirable. 
BLANCHING AND COLD-DIPPING 
The most important steps in canning are 
the preliminary steps of blanching, cold- 
dipping, packing in hot, clean containers, 
adding hot water at once, then immediately 
half sealing jars and putting into the sterilizer. 
Spoilage of products is nearly always due to 
carelessness in one of these steps. Blanching 
is necessary with all vegetables and some 
fruits. It insures thorough cleansing and re- 
moves objectionable odors and flavors and 
excess acids. It starts the flow of coloring 
matter. It reduces the bulk of greens 
and causes shrinkage of fruits, increasing the 
quantity which may be packed in a con- 
tainer, which saves storage space. 
Blanching consists of plunging the vege- 
tables or fruits into boiling water or exposing 
them to steam for a short time. For blanch- 
ing in boiling water place them in a wire 
basket (Fig. 17) or piece of cheesecloth (Fig. 
18). The blanching time varies from one to 
fifteen minutes, as shown in the time-table 
on page 2, and the products should be kept 
under water throughout the period. Begin 
counting time when the articles are first 
placed in boiling water or steam. 
Spinach and other greens should not be 
blanched in hot water. They must be 
blanched in steam to prevent the loss of 
mineral salts, volatile oils and other valuable 
substances. To do this place them in a 
colander and set this 
into a vessel which has 
a tightly fitting cover. 
In this vessel there 
should be an inch or 
two of water, but the 
water must not be al- 
lowed to touch the greens 
(Fig. 12). Another meth- 
od is to suspend the 
greens in the closed 
vessel above an inch or 
two of water. This may be done in a wire 
basket or in cheesecloth. Allow the water to 
boil in the closed vessel fifteen minutes. Ex- 
cellent results are obtained, also, by the use 
of a steam cooker or steam pressure canner. 
When the blanching is complete remove the 
vegetables or fruits from the boiling water 
or steam and plunge them once or twice 
Fig. 11. Wire rack 
for jars. 
