It is not so much a matter of choice, as a matter of safety. All fresh foods naturally contain a combination of water and bacteria. Canning, by definition, creates a vacuum, and a certain bacteria called Clostridium Botulinum thrives in this environment and can reach toxic and potentially fatal levels. By using the correct canning process, you can be assured of proper sterilization. The canning method is determined by the acidity of the foods you wish to preserve. Always follow recipes and directions from a good canning book.
HIGH-ACID FOODS such as most fruits, pickles, relishes and chutney can be processed by the boiling water bath canner or steam canner method. Because of their acidity, they do not provide an environment conducive to the growth of Clostridium Botulinum.
LOW-ACID FOODS such as most vegetables, meats, and seafood need canning temperatures higher than that of boiling water to destroy the deadly bacteria so that it won't grow in the vacuum created by canning. Those foods must be processed by the pressure canner method.
TOMATOES are a special case. By themselves they should be processed as any other vegetable, that is, using the pressure canner method. However, the boiling water bath or steam canner method can be safely used, provided more acidity is added to the tomatoes. For example, use 2 tablespoons of bottled lemon juice or 1/2 teaspoon of citric acid per quart of whole, crushed or juiced tomatoes. You may also use 4 tablespoons of vinegar, but this may impart undesirable flavors to the tomatoes.
It is very rewarding to grow and preserve your own fresh foods, and canning is a means by which you get the added pleasure of extending the life of your harvest with your own two hands, so that you may savor and share the fruits of your labor throughout the year. It is a very caring act for yourself, your family and the environment.
When preparing for a canning project, gather together all the equipment before starting the recipe. This way you will avoid confusion and frustrating delays. Also, try preserving in small batches, especially if you are a beginner. Start as early as possible in the day and allow plenty of time.
Use only the very best-quality fruits and vegetables. Choose vegetables that are still young and tender. Older vegetables are likely to be more fibrous and tough. Immediately after fresh produce is picked, it begins to undergo changes and its vitamin C content declines. Refrigerate fruits and vegetables if you must wait several hours before starting the preserving process and do not wash them until you are ready to use them. However, tomatoes and herbs actually lose flavor at lower temperatures, so it is best to keep them at room temperature. Stand herbs in water, like flowers.
Recycling commercial glass jars, such as mayonaise or pickle jars, for use in home canning may sound practical, but it greatly jeopardizes the preserving process and increases the risk of injury. These jars are simply not designed for canning and are not made with the same sturdy quality as jars made specifically for canning. They may not withstand the lengthy exposure to high temperatures. Clean, glass CANNING JARS, free of chips and cracks, are the ONLY containers you should use for canning. Each jar must have a two-piece lid that consists of a NEW metal vacuum lid and a new or used screw ring. They are the only acceptable lids to use to insure a proper seal. Furthermore, twenty-four hours after the canning process, when the jars have thoroughly cooled, the screw rings must be removed from the jars prior to storing. Screw rings left on jars may rust. If a screw ring is stuck, DO NOT force it and risk breaking the seal. Leave it in place. And never tighten a screw ring further after processing. This can break the seal and leave the food vulnerable to spoilage.
Canning requires adequate preparation of foods and equipment. Scrub sturdy produce under warm water with a soft vegetable brush. Delicate fruits or veggies, however, are best cleaned by soaking in several sinkfuls of water. Place them in a strainer or colander, so they may be lifted out to allow the grit to sink to the bottom. Pit and peel produce as necessary, and cut into uniform size pieces. Keep prepared raw produce in a gallon of water with one teaspoon of ascorbic acid or lemon juice to prevent darkening and brown spots. Make sure the jars you are going to use are thoroughly clean. Should your recipe call for a processing time that is below 10 minutes, pre-washed jars must first be sterilized in a boiling water bath canner. For recipes with processing times above 10 minutes, washing the jars in a dishwasher or hot soapy water is sufficient. Rinse all equipment very thoroughly. Always very diligently read and follow jar manufacturer's directions.
After your jars have been filled and cooled completely (12 to 24 hours), test the lid seal by pressing hard in the center with both thumbs. There should be no movement whatsoever. Any lid that gives or moves downward indicates an improperly sealed jar, which should be refrigerated at once and consumed first, within a day or two. Another way to test seals is to lift the jar by the lid (after the ring has been removed and above a sink fitted with a towel), using the weight of the jar to test the strength of the seal.
A simple cool, dry shelf, in a dark cupboard, is sufficient for storing canned foods. The best temperature for storing canned goods, as recommended by the USDA, is between 50° and 70° F.When you retrieve a jar for consumption, remember to USE YOUR EYES & NOSE FIRST! Look for signs of spoilage:
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