"Wash the jars in real hot water, but they need not be sterilized by boiling them in water; the cooking process later sterilizes the jars as well as the contents. Use only good jars and lids, and always news rubbers. As an extra precaution rubbers may be boiled for a minute or so. Test each jar first for leaks, thus eliminating chance for spoiled contents. Spoiled food also means wasted time. To do this fill the jar with water and screw or clamp the lid on tightly; turn upside down and look for leaks. If using Economy jars or jars of that type, be sure the rim is clean and see that there is no flaw in the rubber or the lids.
After the jars are ready, peel, hull, wash, etc., the vegetables or fruit as the case may be, and blanch or scald as needed. Plunge the basket or sack up and down in the cold water a few times, drain thoroughly and pack carefully into the jars.
The liquid which is poured in after the jars are filled should come only to the shoulder of the jar, but must cover the contents entirely. Do not overpack or overfill jars. Fill them only as directed above. Food expands when heated and this expansion is taken care of by not packing or filling jars too full. It is preferable to add the water, brine or syrup while hot, applying the hot liquid at this time partially expands the contents, as well as raising the temperature to nearer the boiling point, which saves much time. If using jars of the Economy type, be sure to adjust the lid and spring clamp, nothing more need be done until the sterilization or cooking is complete, as the jar automatically seals itself when a vacuum is forced by the cooling of the contents. However, do not remove clamp until contents of jar are cold. If using the Mason jar type, screw the lid on almost tight; if using" the type with a glass lid and a bail clamp, do not tighten the clamp, only adjust it. This is to allow for expansion of the materials during heating.
For Cleaning Fruits and Vegetables
It is not necessary to use cans or jars for putting up preserves, jams, marmalades, pickles, catsup, jellies, etc. For these use some of the ordinary glass containers that may be found in almost every home, such as olive bottles, candy and tobacco jars, pickle bottles, mustard and salad dressing jars, etc. The above products which are preserved by sugar, spices or vinegar, need only to be sealed with paraffine coating, and are nicely adapted to such containers.