Produce preservation has several options

By Kathy Hatfield
Gardening Columnist

Back to Gardening Articles List

Now that the gardening season is winding to a close, it's time to consider preserving some of that produce for the upcoming winter months. There are several methods from which to choose, each with its advantages and disadvantages.

Canning is a fairly economical way to preserve fruits and vegetables, and when produce is picked at peak ripeness just before canning, the nutrient content of canned foods is comparable to fresh or frozen. In some cases, the canning process may actually enhance certain nutrients of some foods. For example, lycopene, an essential phytochemical that is receiving a lot of attention for its role in prostate cancer prevention, is significantly higher in canned tomatoes than in fresh ones.

The disadvantage of canning is that it takes more time than some other methods, and some vegetables get mushy when subjected to the long cooking times.

One method of canning is using a hot water bath. Food is placed in canning jars and heated to a temperature high enough to destroy bacteria. Subsequent cooling creates a vacuum seal that prevents additional bacteria from getting into the jars. This method works for foods with a high acid content, such as pickles, relishes, tomatoes and fruits. Jams and jellies have a high sugar content that prevents bacterial growth and can also be canned using the boiling water bath method.

Low-acid vegetables or meat must be processed in a pressure canner to safely destroy all bacteria. The amount of time required for processing depends on the food being preserved, the size of the jar and elevation above sea level. Old-fashioned methods such as open-kettle or steam canning, and using the microwave or crockpot for canning, are not safe or reliable.

Freezing is probably the method that preserves a taste closest to fresh, and the process is simple and less time-consuming than canning. Again, the quality of the end product depends on the quality of the produce at the time it was frozen. Many vegetables need to be blanched before they are frozen so that the enzymes present in them will not cause a loss of color, flavor or nutrients. The disadvantage to freezing is the cost of obtaining and operating a freezer.

Drying is an economical, though time-consuming way of preserving food. If you don't have a food dehydrator, you can use your oven or our dry climate and abundant sunlight as the energy source. Drying removes the excess moisture from foods so that bacterial growth is stopped. Most of the caloric and nutrient value is retained, although in a more concentrated package.

You can find lots of detailed information on preserving food, including recipes, at the library, from county extension bulletins or online. Make sure you follow directions carefully, especially when canning, to ensure food safety.

Pickled Green Tomato Relish

This is a good recipe if you find you have too many green tomatoes and a frost is approaching.

• 10 pounds small, hard green tomatoes
• 1 1/2 pounds red bell peppers
• 1 1/2 pounds yellow bell peppers
• 2 pounds onions
• 1/2 cup canning or pickling salt
• 1 quart water
• 4 cups sugar
• 1 quart vinegar (5 percent)
• 1/3 cup prepared yellow mustard
• 2 tablespoons cornstarch

Wash and coarsely grate or finely chop tomatoes, peppers and onions. Dissolve salt in 1 quart water and pour over vegetables in large kettle. Heat to boiling and simmer 5 minutes. Drain vegetables and return them to the kettle. Add sugar, vinegar, mustard and cornstarch and mix well. Heat to boiling and simmer 5 minutes. Fill sterile pint jars with hot relish, leaving 1/2-inch headspace. Adjust lids and process 10 minutes in a boiling water bath. Yield: 7 to 9 pints. Consult a good canning reference if you are not familiar with hot water bath canning.

Peach Leather

Wash ripe peaches, remove seeds and cut into pieces. Purée fruit in a blender until smooth. To retain color and prevent darkening, add 1/8 teaspoon of ascorbic acid or 2 teaspoons of lemon juice to each 2 cups of fruit. If you want sweeter fruit, add corn syrup or honey to taste. Granulated sugar can be used, but you might get crystals forming on the fruit leather.) Pour the pureed fruit onto plastic wrap-lined trays. Spread the fruit evenly so that it is about 1/8 inch thick. Dry in a food dehydrator, the oven or in the sun.