FOOD SAFELY - FOODBORNE ILLNESSfoodborneillness.org/cfi-library/CFI-factsheet-Canning...CANNING Why...

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Why is canning an effective method for preserving food? Canning inactivates enzymes. Enzymes are proteins that speed up chemical reactions. Enzymes are naturally found on foods and help fruits and vegetables to ripen. After fruits and vegetables are harvested, enzymes are still active. Enzymes can cause fruits and vegetables to spoil. High heat during the canning process inactivates the enzymes and preserves the food. Canning kills spoilage bacteria. Spoilage bacteria generally does not make people sick, but it can cause undesired flavors, textures, and tastes on food. The high heat used during canning kills spoilage bacteria. o Some bacteria need oxygen to grow. The canning process forms a vacuum-seal on jars and prevents oxygen from entering. This prevents bacteria from growing and keeps foods from spoiling. o Bacillus coagulans is a spoilage bacteria that produces a sour odor and flavor in improperly canned tomatoes. Even though Bacillus coagulans will not make you sick, the sour smell and taste of a spoiled jar of tomatoes is enough to make you throw away the product. Canning inactivates Clostridium botulinum spores. Botulism is a serious foodborne illness that can cause death if consumed. Botulism is caused by Clostridium botulinum spores. These spores are found on raw fruits and vegetables. Clostridium botulinum can produce the deadly toxin when it is in an environment without oxygen. The vacuum-seal on jars provides an oxygen-free environment that will allow Clostridium botulinum spores to grow IF the canning process is not carried out correctly. In order to kill Clostridium botulinum spores, jars must be heated to 250 o F for low acid foods (pH above 4.6). Following tested recipes and canning methods is necessary to ensure Clostridium botulinum is killed and does not grow in canned food. CANNING FOOD SAFELY Fruits and vegetables not only taste great but also provide vitamins, minerals, and fiber to our diets. During growing season, fruits and vegetables are abundant in farm markets and grocery stores. But, over time, those same juicy, crisp fruits and vegetables will spoil. The high water and nutrient content of produce provides a perfect medium for the growth of bacteria, which can make produce spoil and also make us sick. When many of us see the bounty of summer produce, our thoughts turn to home canning – ensuring that through the year, our tables will be filled with beans, tomatoes, homemade jams, and other treats. While canning provides a great method for preservation, knowing the correct method and recipe for canning is a must. Improper canning can lead to sickness or, even worse, death. By applying heat and removing oxygen, careful canning helps inactivate spores on fruits and vegetables, greatly extending the shelf life of the produce and providing your family with fruits and vegetables that are safe to eat all year long.

Transcript of FOOD SAFELY - FOODBORNE ILLNESSfoodborneillness.org/cfi-library/CFI-factsheet-Canning...CANNING Why...

Page 1: FOOD SAFELY - FOODBORNE ILLNESSfoodborneillness.org/cfi-library/CFI-factsheet-Canning...CANNING Why is canning an effective method for preserving food? Canning inactivates enzymes.

Why is canning an effective method for preserving food?

Canning inactivates enzymes. Enzymes are proteins that speed up chemical reactions. Enzymes are naturally found on foods and help fruits and vegetables to ripen. After fruits and vegetables are harvested, enzymes are still active. Enzymes can cause fruits and vegetables to spoil. High heat during the canning process inactivates the enzymes and preserves the food.

Canning kills spoilage bacteria. Spoilage bacteria generally does not make people sick, but it can cause undesired flavors, textures, and tastes on food. The high heat used during canning kills spoilage bacteria. o Some bacteria need oxygen to grow. The canning process forms a vacuum-seal on jars and prevents

oxygen from entering. This prevents bacteria from growing and keeps foods from spoiling. o Bacillus coagulans is a spoilage bacteria that produces a sour odor and flavor in improperly canned

tomatoes. Even though Bacillus coagulans will not make you sick, the sour smell and taste of a spoiled jar of tomatoes is enough to make you throw away the product.

Canning inactivates Clostridium botulinum spores. Botulism is a serious foodborne illness that can cause death if consumed. Botulism is caused by Clostridium botulinum spores. These spores are found on raw fruits and vegetables. Clostridium botulinum can produce the deadly toxin when it is in an environment without oxygen. The vacuum-seal on jars provides an oxygen-free environment that will allow Clostridium botulinum spores to grow IF the canning process is not carried out correctly. In order to kill Clostridium botulinum spores, jars must be heated to 250oF for low acid foods (pH above 4.6). Following tested recipes and canning methods is necessary to ensure Clostridium botulinum is killed and does not grow in canned food.

CANNING FOOD SAFELY

Fruits and vegetables not only taste great but also provide vitamins, minerals, and fiber to our diets. During growing season, fruits and vegetables are abundant in farm markets and grocery stores. But, over time, those same juicy, crisp fruits and vegetables will spoil. The high water and nutrient content of produce provides a perfect medium for the growth of bacteria, which can make produce spoil and also make us sick.

When many of us see the bounty of summer produce, our thoughts turn to home canning – ensuring that through the year, our tables will be filled with beans, tomatoes, homemade jams, and other treats. While canning provides a great method for preservation, knowing the correct method and recipe for canning is a must. Improper canning can lead to sickness or, even worse, death.

By applying heat and removing oxygen, careful canning helps inactivate spores on fruits and vegetables, greatly extending the shelf life of the produce and providing your family with fruits and vegetables that are safe to eat all year long.

Page 2: FOOD SAFELY - FOODBORNE ILLNESSfoodborneillness.org/cfi-library/CFI-factsheet-Canning...CANNING Why is canning an effective method for preserving food? Canning inactivates enzymes.

Where can you get recipes that are tested and up to current food-safety standards? Many people remember delicious recipes that have been handed down through the family, but it’s important to remember that the way mom or grandma did things may have changed, especially when it comes to safe food preservation. These three sources are excellent places to find canning recipes. They have hundreds of recipes that have all been thoroughly tested to be safe, so you’re sure to find something close to that recipe you’re trying to recreate!

USDA Complete Guide to Home Canning, 2006.

So Easy to Preserve, by Andress et al. University of Georgia Extension Service, Fifth Edition, 2006. Ball Blue Book of Preserving, 100th Anniversary Edition.

What are the common methods of canning at home to ensure your food is safely canned?

Pressure Canning

Necessary for low acid foods such as vegetables, meats, and soups, a pressure cooker kills all spoilage bacteria and Clostridium botulinum spores.

BASIC STEPS: Select a tested recipe. Follow the recipe. Check to ensure the integrity of the canner. Use a two-piece lid. Fill jar and secure the lid to the jar. Place the jar in a pressure canner to treat the jar with high pressure and high temperature. Be sure to vent the canner for 10 minutes before and after you reach and hold the pressure needed in

your recipe. Wait for the canner to cool before removing the lid For more information, please see the USDA’s Completed Guide to Home Canning, or the National

Center for Home Food Preservation at www.uga.edu/nchfp/ Boiling Water Canning

High acid foods (with a pH at or below 4.6), such as fruits and pickled products, naturally have a level of acidity that hinders the germination of Clostridium botulinum spores. For these foods, a boiling water bath canning method may be used.

BASIC STEPS: Follow a recipe to guarantee the pH of the final food product is at or below 4.6. Place the jar in a pot with a rack in the bottom and a tight-fitting lid on top to create a boiling water

bath. Be sure the water level is 1-2” above the top of your jars. Process the jar in the water bath for the time specified in your tested recipe.

Prior to canning, consult the USDA's Complete Guide to Home Canning, which provides important instructions on preparing and canning specific food products. Sources: 1. “Fruits & Veggies Matter: Fruit & Vegetable Benefits: Color Guide | CDC,” http://www.fruitsandveggiesmatter.gov/benefits/nutrient_guide.html. 2. Canned Foods: Principles of Thermal Process Control, Acidification and Container Closer Evaluation. Washington, D.C.: GMA Science And Education Foundation, 2007. 3. “Common Food Safety Questions from FSIS - Bacteria, Spoilage,” http://www.fsis.usda.gov/help/FAQs_Food_Spoilage/index.asp. 4. “Canning Tomatoes and Tomato Products,” http://www.ext.colostate.edu/pubs/foodnut/09341.html. 5. “National Center for Home Food Preservation | USDA Publications,” http://www.uga.edu/nchfp/publications/publications_usda.html.