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Bring Summer Back this Winter!

Posted by Mary Liz Wright -


The days are beginning to shorten, I can hear the locusts calling –fall is in the air. Our gardens know it too. The plants are offering their last fruits before they succumb to frost. Will we be ants or grasshoppers? How will we prepare for the winter? Perhaps you have thought of preserving your harvest. You walked through the exhibit hall at your county fair and thought the canned goods were beautiful. They are and the taste is unparalleled. Home grown, home canned produce tastes better. There is a great satisfaction knowing that you planted a seed and ended with jars full of spaghetti sauce or pickles. How can you do that?

I often hear that "canning is scary", " Aunt Martha's pressure canner blew peaches all over her ceiling" from my food preservation workshop participants. And, although accidents can happen, with proper knowledge and up to date instructions canning is not only enjoyable it is easy. Food preservation is science, however, it is not rocket science.

Before you dust off Grandma's canner let's talk about safety. Make sure your canner has the UL seal of approval and follow the manufacturer's directions exactly. Never use the open kettle or oven methods of canning---these methods are not safe! Do not "make up" recipes or add extra ingredients. Canning is a scientific process that can preserve the taste of summer for your family to enjoy in those long cold months of winter, if you follow some basic guidelines.

Begin with wholesome, unblemished fruits and vegetables. Wash both the produce and your hands after coming in from the garden; it is best to use warm water. The deadly microbe Clostridium botulinum lives in the soil and on most fresh food surfaces—it really does not pose a threat until it is exposed to its favorite environment—the moist, low acid, low oxygen atmosphere inside a canning jar full of food. This deadly germ can be destroyed by using an approved canner and following recipes exactly to ensure proper acid levels of foods. Follow instructions and recipes from approved sources (USDA, Extension, Ball, Kerr, Mrs. Wages). Please go to or call your local Extension office for more information.
Below are the most frequently asked questions :

  1. Must I process jars in a boiling water bath?

Yes, all foods must be processed. High acid foods (fruits, jams, jellies, pickled products and tomatoes that have been acidified) can all be processed in a boiling water bath—follow recipe instructions for times.

  1. Am I allowed to "process" foods like my grandmother?

No, the following methods are not considered safe!

  • Open-kettle method; no processing is done, and thus is unsafe
  • Sealing jams, jellies, preserves, and butters with wax or paraffin; often allows harmful mold growth.
  • Do not use recipes from celebrity chefs and unreliable internet sources; they often use unsafe, outdated, non-research based methods
  • Do not invert hot jars of jam, jelly, etc.
  • Steam canning; inadequate research for processing times
  • Do not use a microwave oven, electric oven, slow cooker, crock pot, convection oven, dishwasher, sun canning, or other methods besides a Boiling Water Bath Canner or Pressure Canner
  1. Can I process green beans in a boiling water bath if I boil it for 3 hours?

No, low acid foods must be processed in a pressure canner to kill clostridium botulinum,

a deadly form of food poisoning.

Low-acid foods include red meats, seafood, poultry, milk, and all fresh vegetables. Most mixtures of low-acid and acid foods are also low acid, unless their recipes include enough lemon juice, citric acid, or vinegar to make them acid foods.

Botulinum spores are very hard to destroy at boiling-water temperatures; the higher the canner temperature, the more easily they are destroyed. Therefore, all low-acid foods should be sterilized at temperatures of 240° to 250°F, attainable with pressure canners operated at 10 to 15 PSIG.

  1. Must I add lemon juice to my tomatoes?
    1. Yes. To ensure safe acidity in whole, crushed, or juiced tomatoes, add two tablespoons of bottled lemon juice or 1/2 teaspoon of citric acid per quart of tomatoes. For pints, use one tablespoon bottled lemon juice or 1/4 teaspoon citric acid. Acid can be added directly to the jars before filling with product. Four tablespoons of a 5 percent acidity vinegar per quart may be used instead of lemon juice or citric acid. However, vinegar may cause undesirable flavor changes.
  2. Can food be re-canned if the lid does not seal?
    1. Yes, if discovered within 24 hours. To re-can, remove the lid and check the jar rim for nicks. Change the jar, if nicks are present, add a new lid and reprocess using the original processing time.
  3. Do I really need to leave a certain amount of head space?
    1. Yes, leaving the specified amount of head space in a jar is important to assure a vacuum seal. If too little headspace is allowed the food may expand and bubble out when air is being forced out from under the lid during processing. The bubbling food may leave a deposit on the rim of the jar or the seal of the lid and prevent the jar from sealing properly. If too much head space is allowed, the food at the top is likely to discolor. Also, the jar may not seal properly because there will not be enough processing time to drive all the air out of the jar.
  4. How long will canned food keep?
    1. For best quality, use within a year.
  5. Is it necessary to sterilize jars before canning?
    1. Only if the jars are to be processed in a water bath and only if the processing time is less than 10 minutes.
  6. Is it safe to can foods without salt?
    1. Yes. Salt is used for flavor only and is not necessary to prevent spoilage. If salt is used, it must be canning salt. Table salt may make the contents of the jar cloudy.
  7. Can I can my own salsa recipe?
    1. NO! Salsas are usually mixtures of acid and low-acid ingredients. The specific recipe, and sometimes preparation method, will determine how the salsa should be processed. The process must be scientifically determined for each recipe. You must use a tested recipe! Contact your local Extension office for a recipe. If you want to customize your salsa, do it after it has been processed, just before you serve it!

  1. Can I can bread or cake in a jar?
    1. These items are not really "canned". Rather the batter is baked in the jar and then a lid is placed on the jar while still hot. Cakes and breads are low acid foods that have the potential for supporting the growth of bacteria like Clostridium botulinum.
  2. Can I use artificial sweeteners when canning fruit?
    1. It is best to add these types of sweeteners just prior to serving. Saccharin-based sweeteners can turn bitter and Aspartame-based sweeteners can lose their sweetening power during processing.

Sugar is added to improve flavor, help stabilize color, and retain the shape of the fruit. It is not added as a preservative.

  1. How do I can oil with herbs? Can I can pesto?
    1. No, canning this mixture is not safe, freeze it.


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