Home-canned foods will be no better than the raw products with which you
begin. Fruits and vegetables should be of good quality with no bruises
or soft spots. Be sure to choose fresh, firm, ripe fruits and young
tender vegetables. Use them before they lose their freshness. Do not use
overripe produce because some foods lose acidity as they mature, and the
recommended processing time may not be adequate.
Wash all fruits and vegetables thoroughly, but gently, to remove dirt
which contains bacteria. Wash small quantities at a time under running
water or through several changes of water. Lift fruits and vegetables
out of the water so the dirt will not resettle on the food. Do not let
fruits or vegetables soak, as they may lose flavor and food value. Peel
and cut or slice produce as indicated in instructions for each specific
fruit or vegetable.
Fruits and vegetables may be packed raw into jars, or preheated and
packed hot. Raw or cold pack means that raw, unheated food is placed in
jars and covered with boiling hot sirup, juice, or water. When foods are
hot packed they are heated in sirup, water or steam, or juice for a
specified length of time and then packed hot into jars.
Most raw fruits and vegetables can be packed fairly tightly into
containers because they cook down during processing. However, raw corn,
lima beans, and peas should be packed loosely because they expand during
processing.
Hot food should be packed fairly loosely. It should be at or near the
boiling temperature when packed. There should be enough sirup, water, or
juice to fill in around the solid food in the container and to cover the
food. Food at the top of the container may darken if not covered with
liquid.
Do not overpack containers as this may result in underprocessing. It is
necessary to leave headspace between the lid and the top of the food or
liquid in the jar because there will be some expansion of food during
processing. The amount of headspace varies with the product, style of
pack, and method of heat sterilization, so follow directions for each
fruit or vegetable.
When using the flat metal lid with sealing compound, put the lid on a
clean jar rim, with sealing compound next to the glass. Then screw the
metal band down firmly. The lid will still have enough "give" to let
steam escape during processing. Do not tighten the band further after
removing the jar from the canner.
When using the porcelain-lined zinc cap, fit the wet rubber ring down on
the jar shoulder. Fill the jar and wipe clean the rubber ring and jar
rim. Screw the cap down firmly and turn back ¼ inch. When the jar is
removed from the canner, tighten the cap to complete the seal.