EXTENSION COURSE IN VEGETABLE FOODS. 63 
LESSON XIII. PRESERVING AND CANNING VEGETABLES. 
The home canning of fruits and vegetables is a matter of more 
importance to those who grow such products than to those who 
must buy them in any case. The cost of labor and fuel, added to the 
cost of the raw material, makes it wiser for many to buy the canned 
article. But there is no question that the surplus products of the 
home garden should be preserved in some form for future use. A 
number of the publications of the United States Department of 
Agriculture treat different phases of this subject fully and can be 
used as supplemental textbooks for lessons. (See especially Ref. 
Nos. 1, 4, 5, 6.) 
The essential points in all canning are few—absolute cleanliness, 
good sterilization, and suitable containers—which mean the destruc- 
tion and exclusion of molds, bacteria, and spores. 
Poisonous or doubtful preservatives never should be used. The 
housekeeper should limit herself to the use of the approved household 
preservatives, such as spice, vinegar, salt, wood, and smoke. The 
use of sugar, salt, vinegar, and spices as flavorings has gone on so 
long that it is frequently forgotten that such use is very often sec- 
ondary to their preservative effect. 
A practical point worth remembering in canning and preserving 
is that, roughly speaking, 1 quart of some vegetables, for instance, 
spinach well packed down, onions, and cranberries, will weigh prac- 
tically a pound, while with others, such as apples, cucumbers, and 
peas, the weight of a quart would be more nearly 2 pounds. When 
canning vegetables or preparing them for the table it is well to re- 
member that on an average a quart of vegetables, as purchased, will 
be required to fill a pint jar or dish; the shrinkage being due to 
loose measure, the removal of skin, and other inedible portions, and 
condensation in cooking. 
PRESERVING WITH SUGAR. 
The earliest method of preserving fruit aside from drying appears 
to have been to coat it with honey and allow it to dry somewhat. 
From that may have been derived the plan of packing in jars and 
filling the spaces with strained honey. This might have been the 
result of observation of the way in which flowers, etc., accidentally 
coated with honey retained their original freshness. In any case it 
was unconscious application of the fact that bacteria and molds do 
not grow readily in the presence of concentrated sugar solutions. 
Preserving with sugar is, of course, more important for fruits 
than for vegetables, but is worth consideration here, partly because 
it shows an important principle in the general science of food 
