most popular canning method.
Find new recipes to preserve old favorites for more variety in your pantry.
Understand why water-bath canning is safe for certain foods and not for others.
Chapter 4
Come On In, the Water’s Fine! Water-Bath Canning
IN THIS CHAPTER
Discovering water-bath canning
Recognizing high-acid foods
Stepping up to high-altitude canning
Knowing the proper processing procedures
With water-bath canning, you essentially use a special kettle to boil filled jars for a certain amount of time. Common foods for water-bath canning include fruits and tomatoes, as well as jams, jellies, marmalades, chutneys, relishes, pickled vegetables, and other condiments.
You’re probably wondering whether water-bath canning is safe for canning food at home. Rest assured: The answer is a most definite “Yes!” — provided that you follow the instructions and guidelines for safe canning.
In this chapter, you discover which foods are safely processed in a water-bath canner and step-by-step instructions for completing the canning process. In no time, you’ll be turning out sparkling jars full of homemade delicacies to dazzle and satisfy your family and friends.
Water-Bath Canning in a Nutshell
Water-bath canning, sometimes referred to as the boiling-water method, is the simplest and easiest method for preserving high-acid food, primarily fruit, tomatoes, and pickled vegetables.
To water-bath can, you place your prepared jars in a water-bath canner, a kettle especially designed for this canning method (see the section, “Key equipment for water-bath canning,” for more on the canner and other necessary equipment). You then bring the water to a boil and maintain that boil for a certain number of minutes, determined by the type of food and the size of the jar. Keeping the water boiling in your jar-filled kettle throughout the processing period maintains a water temperature of 212 degrees. This constant temperature is critical for destroying mold, yeast, enzymes, and bacteria that occur in high-acid foods.
Water-bath canning is one of the two recommended methods for safely home-canning food (the other method is pressure canning, covered in Chapter 9). Although each processing method uses different equipment and techniques, the goal is the same: to destroy any active bacteria and microorganisms in your food, making it safe for consumption at a later time. This is accomplished by raising the temperature of the food in the jars and creating a vacuum seal.
Water-bath canning and pressure-canning methods aren’t interchangeable because the temperature of a water bath only reaches 212 degrees, while the temperature of a pressure canner reaches 240 degrees, the temperature necessary to safely process low-acid foods. Boiling for any amount of extra time should not replace the higher temperature of a pressure canner. For more on pressure canning, go to Chapter 9.
Foods you can safely water-bath can
You can safely water-bath can only high-acid foods — those with a pH factor (the measure of acidity) of 4.6 or lower. So just what is a high-acid food? Either of the following.
Foods that are naturally high in acid: These foods include most fruits.
Low-acid foods that you add acid to, thus converting them into a high-acid food. Pickled vegetables fall into this category, making them safe for water-bath canning.You may change the acid level in low-acid foods by adding an acid, such as vinegar, lemon juice, or citric acid, a white powder extracted from the juice of acidic fruits such as lemons, limes, or pineapples. Some examples of altered low-acid foods are pickles made from cucumbers, relish made from zucchini or summer squash, and green beans flavored with dill. Today, tomatoes tend to fall into this category. They can be water-bath canned, but for safety’s sake, you add a form of acid to them.
If your recipe doesn’t tell you which processing method (water-bath canning or pressure canning) is appropriate for your food, don’t guess. Instead, use litmus paper to test the pH level of your food (see Chapter 3). If your food has a pH of 4.6 or lower, use the water-bath canning method; if it has a pH of 4.7 or higher, use the pressure-canning method.
Key equipment for water-bath canning
Just as you wouldn’t alter the ingredients in a recipe or skip a step in the canning process, you don’t want to use the wrong equipment when you’re home-canning. This equipment allows you to handle and process your filled jars safely.
The equipment for water-bath canning is less expensive than the equipment for pressure canning (check out Chapter 9 to see what equipment pressure canning requires). Water-bath canning kettles cost anywhere from $25 to $45. You may want to purchase a “starter kit” for about $50 to $60, which includes the canning kettle, the jar rack, a jar lifter, a wide-mouth funnel, and jars.
Following is a list of the equipment you must have on hand, no exceptions or substitutions, for safe and successful water-bath canning.
A water-bath canner: The water-bath canner consists of a large kettle, usually made of porcelain-coated steel or aluminum, that holds a maximum of 21 to 22 quarts of water, has a fitted lid, and uses a rack (see the next item) to hold the jars (see Figure 4-1). Do not substitute a large stock pot for a water-bath canner. It is important for the jars to be sitting off the bottom of the canner, and racks that fit this purpose are included in your canner kit. Although aluminum is a reactive metal (a metal that transfers flavor to food coming in direct contact with it), it’s permitted for a water-bath canner because your sealed jar protects the food from directly touching the aluminum.
A jar rack: The jar rack for a water-bath canner is usually made of stainless steel and rests on the bottom of your canning kettle. It keeps your jars from touching the bottom of the kettle, or each other, while holding the filled jars upright during the water-bath processing period. The rack has lifting handles for hanging it on the inside edge of your canning kettle (refer to Figure 4-1), allowing you to safely transfer your filled jars into and out of your kettle.FIGURE 4-1: A water-bath canning kettle with the rack hanging on the edge of the kettle.
Canning jars: Canning jars are the only jars recommended for home-canning. Use the jar size recommended in your recipe. For more on canning jars, refer to Chapter 2.
Two-piece caps (lids