_Raw pack or hot pack._—Fruits and vegetables may be packed raw into
glass jars or tin cans or preheated and packed hot. In this publication
directions for both raw and hot packs are given for most of the foods.
Most raw fruits and vegetables should be packed tightly into the
container because they shrink during processing; a few—like corn, lima
beans, and peas—should be packed loosely because they expand.
Hot food should be packed fairly loosely. It should be at or near
boiling temperature when it is 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 tends to darken if not covered with liquid. It takes from
½ to 1½ cups of liquid for a quart glass jar or a No. 2½ tin can.
_Head space._—With only a few exceptions, some space should be left
between the packed food and the closure. The amount of space to allow at
the top of the jar or can is given in the detailed directions for
canning each food.