There are many sizes of canning jars. Use these guidelines for each.
Quart jars: Use these for large food, such as whole tomatoes, or for a generous amount, such as spaghetti sauce or soup for a crowd. The jars come in wide-mouth and regular-mouth styles.
Pint jars: The most versatile-size jar, these containers hold nearly anything: smaller amounts of sauce, vegetables to serve a few people, pickles, and relishes. The jars come in wide-mouth and regular-mouth styles.
Half-pint jars: These jars sport straight interior sides that allow you to get every last bit out of each jar. Wide-mouth half-pint jars are shorter than regular-mouth jars. Some have a quilt or other design on exterior.
4-ounce jars: These small jars hold amounts you'll use up quickly or wish to can in small portions.
Decorative jars: For refrigerator-pickled foods that don't require heat processing, decorative glass jars work fine. Just make sure you clean the jars in hot soapy water and rinse well before filling them.
Vintage jars: Old canning jars with colored glass or spring-type lids are pretty collector pieces, but they shouldn't be used in modern canning. They have irregular sizes, might crack, and don't seal properly.
Use only standard canning jars and inspect them carefully; discard any that are cracked or chipped. To remove mineral deposits or hard-water film, soak empty jars in a solution of 1 cup vinegar per gallon of water. Look for canning jars in hardware, discount, or grocery stores.
Wide-mouth canning jars make it easier to pack whole fruit and vegetables into a jar.
Regular-mouth canning jars are the quart and pint jars with shoulders. Regular mouth half pint jars are taller than wide-mouth ones.
Use screw bands and canning lids according to the manufacturer's directions. Screw bands secure lids to jars during processing. Removing the bands after processing is a matter of choice. Although they are no longer needed, the bands do provide some cushioning between jars when stacked on shelves. Screw bands can be reused only if they are not bent or rusty. Look for bands and lids in hardware, discount, or grocery stores.
Canning lids are designed for one-time use and are best purchased for the current canning season (some sealing compounds lose effectiveness when stored). Lids are sized to fit regular-mouth and wide-mouth jars. When purchasing new jars, lids and bands will be included, but you can also purchase lids separately.
The sealing compound is the red substance on the underside of the lid. It helps seal the lid onto the jar.
A boiling-water canner heats jars to 212 degrees F, enough to kill microorganisms found in high-acid foods (pH 4.6 or lower). The rack allows water to flow beneath the jars for even heating and has handles that allow you to lower and lift jars easily into the hot water. Canners come in different sizes and finishes. A traditional speckled enameled finish resists chips and rust. High-end boiling-water canners are available in sleek polished steel.
If you have a large stockpot that has a tight-fitting lid and holds several jars a few inches deeper than their height, you can use that as a canner. You will need a rack to set jars up off the bottom of the pot to allow water to flow under them and heat the jars evenly.
Use this type of canner for fruits, tomatoes (if lemon juice or other acidic ingredient is added), pickles, relishes, jams, jellies, and marmalades.
Use this type of canner for low-acid foods (pH 4.7 or lower), such as vegetables. It will include a heavy pot with a rack, a tight-fitting lid that has a vent or petcock, a dial or weighted pressure gauge, and a safety fuse. Pressure canners allow foods to be heated to 240 or 250 degrees F and to be held at that temperature for as long as necessary. Each type of pressure canner is different; always review the manufacturer's directions. Look for canners where cooking equipment is sold.
Jar lifter: This tool lifts jars firmly and securely in and out of hot water. Use two hands and squeeze firmly. You can also use kitchen tongs, but they are not as secure.
Jar funnels: Much wider and shorter than other funnels, these come in both wide-mouth and regular-mouth versions. They're invaluable for preventing spills when filling canning jars.
Combination ruler/spatula: The notched end is calibrated to match the most common headspace in jars. The tool is somewhat flexible and has a tapered end, making it the ideal tool for slipping in along the sides of filled jars to release air bubbles.
Magnetic lid wand: This wand enables you to drop lids and rings into the hot water of the canner to sterilize them, soften the sealing compound, and easily lift them out from among jars and the racks; there's no need to heat them in a separate pan.