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Tag: Food Preservation

Preserving Melons

Posted on by Karen Blakeslee
cantaloupe
Fresh cantaloupe
Photo: USDA ARS

Melons are another summer treat! They are best eaten fresh, but there freezing them for later use is an option.

Rinse with water and scrub the rind to remove dirt, then dry. Slice the melon into cubes or use a melon baller. Place pieces on a parchment-lined baking sheet and freeze. Then place frozen melon pieces in a freezer container. Just know the texture may change during freezing.

Melons, by themselves are not suitable for canning. In fact, they are a low acid food. There are a couple options to make cantaloupe into pickles or a conserve at www.canr.msu.edu/uploads/resources/pdfs/melons_(e3250).pdf. Watermelon rind can be made into pickles also. See https://nchfp.uga.edu/how/can_06/watermelon_rind.html.

 

Why is Headspace Important in Canning?

Posted on by Karen Blakeslee
Headspace
Photo: USDA Complete Guide to Home Canning

Headspace is the space in the jar between the inside of the lid and top of the food or its liquid.  The amount of headspace needed depends on the type of food being processed.

If the jars are filled too full the contents may boil out during processing.  Solids or seeds may be caught under the sealing compound and prevent the jar from sealing.

If too much headspace is left at the top of the jar, the processing time may not be long enough to drive out all the extra air from the top of the jar.  This would mean that a tight vacuum seal may not be formed.  Also, the air left inside the jar could cause the food to discolor.

For the correct headspace for each food, check the processing directions for each specific food.

Starchy foods, such as beans or potatoes, tend to swell when heated and therefore require more headspace.

The extent of expansion during processing  it determined by the air content in the food and by the processing temperature.  Air expands more at higher temperatures.

The USDA Complete Guide to Home Canning recommends the following headspace measurements:

  • Jams and Jellies—1/4 inch
  • Fruits and tomatoes to be processed in a boiling water bath—1/2 inch
  • Low acid food to be processed in a pressure canner—1– to 1-1/4 inches

Source: USDA Complete Guide to Home Canning and National Center for Home Food Preservation

 

Freezing Food for the Fair

Posted on by Karen Blakeslee
Fair judging
Kansas State Fair, Photo: KSRE Flickr

To help save time and stress at county fairs, prepare food entries early and freeze them.  Most baked goods freeze well and can still be blue ribbon quality.  This includes cookies, yeast and quick breads, and cakes.  Here are some tips:

  • Bake the product as usual. Cool completely!  This helps prevent condensation inside the wrapping and development of ice crystals.
  • Use moisture-vapor resistant packaging. This includes freezer-safe plastic containers or bags, heavy-duty aluminum foil, and rigid containers.
  • Separate layers of cookies with wax paper or parchment paper.
  • If a cake or bread is to be frosted, freeze the product only and frost after it is thawed.
  • Make pie crusts ahead of time and freeze. Freezing whole prepared pies can cause the filling to soak into the crust.
  • Thaw all baked goods in the freezer packaging. They can be thawed at room temperature.  Remove from the freezer the night before the fair.  Once thawed, repackage into the proper packaging according to your fair rules.

Source:  Univ. of Georgia, www.uga.edu/nchfp/publications/uga/FreezingPreparedFoods.pdf

Source:  Univ. of Georgia, www.uga.edu/nchfp/publications/uga/FreezingPreparedFoods.pdf

 

Safely Preserving Tomatoes

Posted on by Karen Blakeslee
Canned tomatoes
Canned tomatoes, University of Georgia

Tomatoes are borderline in pH between acid and low acid foods, so the USDA preparation directions for these products call for acidification to allow a less severe heat treatment than would be required without it. To ensure safe acidity in whole, crushed, or juiced tomatoes, add two tablespoons of bottled lemon juice or ½ teaspoon of citric acid per quart of tomatoes. For pints, use one tablespoon bottled lemon juice or ¼ teaspoon citric acid. Add acid directly to jars before filling. Sugar may be added to offset an acid taste, if desired, but the acid cannot be decreased to taste.

No matter how you choose to can your tomatoes, all steps in preparing and cooking the foods still need to be followed for the process time(s) printed with them. The process times are very different for tomatoes packed in water compared to tomato juice or without added liquid. For many of these tomato products, there are canning options for both boiling water and pressure canning available in our directions.

Source: https://nchfp.uga.edu/tips/summer/canned_tomato_types.html

See KSRE Preserving Tomatoes for more information

 

Reminder About Elderberries

Posted on by Karen Blakeslee

While elderberries are a fruit, they are actually low acid which can be problematic for canning.

There are some guidelines and instructions to make elderberry jam or jelly safely at www.rrc.k-state.edu/preservation/doc/july-august-presnews2021.pdf.

Do not use low or no-sugar pectin as sugar is critical for safety. Do not replace any sugar with honey.

Freezing is always a safe option for preserving elderberries.

Food Preservation Resources

Posted on by Karen Blakeslee

NCFSENAs gardens are getting planted, so are plans to preserve the harvest to enjoy in later months. To safely preserve food, education is key to know the best method and recommendations. The North Central Food Safety Extension Network is working to provide educational resources for a unified message. Here are some resources for your use.

Jar It Right! – Best practices for canning with Mason-type jars. Be sure jars are clean and free of nicks or cracks. Wash jars before use. Warm jars before filling with prepared food. Sterilizing jars is not required for processing times longer than 10 minutes.

Put a Lid On It! – Best practices for ensuring a safe seal on canning jars. Wash lids prior to use, do not heat or boil lids as they may not seal properly. Clean the jar rim before applying the lid to reduce seal failures.

Pressure Can It Right! – Tips to safely use a stovetop or electric pressure canner. Pressure canners must be used for canning plain vegetables or any meat product to destroy Clostridium botulinum spores.

Steam Can It Right! – Guidelines on using a steam canner for preserving high acid foods. This method can be used for any water bath canned food with a total processing time of 45 minutes.

Learn more at www.ncrfsma.org/north-central-food-safety-extension-network-ncfsen.

 

Peeling Produce Before Preserving

Posted on by Karen Blakeslee
Peeling Carrots
Peeling carrots
Photo: KSRE Douglas county

When preserving food, there are certain steps to take to be sure the food is safe after preserving. One of those steps is peeling produce. Why? Bottom line is food safety.

While the outside peels of many types of produce are nutritionally beneficial, those peels can hold onto microorganisms and dirt. Rinsing produce with water before peeling is the first step to remove microorganisms and dirt. Peeling physically removes that outer layer and drastically reduces contamination. After a final rinse with water, the food is ready to preserve.

Therefore, when a recipe says to peel the produce, it must be done. That recipe was developed and researched with that step included. Choosing to skip the peeling step can result in improperly processed food and spoilage.

Don’t let those peels go to waste! Save them to make a vegetable stock to freeze and use in soups and other recipes. Add them to your garden compost pile or feed your animals.

Source: National Center for Home Food Preservation

 

Easy Peeling

Posted on by Karen Blakeslee

While a vegetable peeler or paring knife is useful to peel produce, for some foods there is an easier method.

For tomatoes, blanching them in hot water works well and less flesh is lost. Heat a large stockpot of water to boiling. Core tomatoes or poke the skin with a knife and place in the hot water for about 60 seconds or until the peel starts to pull away from the flesh. Remove them from the hot water and plunge them into an ice water bath to stop the cooking process. Gently rub the peel and it should slip off easily.

This method works well for fruits with thin skins such as peaches and nectarines.

Peeling produce is an important step to preserve food safely in  all methods of food preservation.

 

A Caution about Fats and Oils in Canning

Posted on by Karen Blakeslee
Canned beef chunks. Trim excess fat for best results.
Photo: KSRE

While fat or oil can enhance flavor and texture in many recipes, when it comes to canning, fat and oil can lead to food safety problems. There are very few recommendations to use fat or oil in home food preservation.

Research shows that fats and oils can surround bacterial spores, if present, and protect them from heat destruction. This allows them to survive in the jar of food.

In canning meat it is best to use the leanest meat possible. Fat can boil up during canning and interfere with the sealing compound of the lid. Use the proper amount of headspace for best results.

Do not add oil to home canned tomato sauces, salsa or marinated vegetables. Making flavored oils that contain herbs, garlic, peppers, etc. can provide favorable conditions for Clostridium botulinum to survive when stored at room temperature. Store these in the refrigerator.

Besides canning meat, poultry and fish, there are very few researched canning recipes that use oil. Learn more at www.rrc.k-state.edu/preservation/index.html.

Source: https://extension.psu.edu/caution-canning-with-fats-and-oils

 

From Freezing to Canning: The Role of Temperature in Preserving Food

Posted on by Karen Blakeslee

North Dakota State University Extension offers a webinar series entitled Field to Fork. This series offers education about growing, preparing, preserving and selling vegetables and fruits. Presenters for these webinars are from several universities in the North Central region.

A couple of interest to home food preservation include:

See the Field to Fork website for the archives of all webinars and sign up for remaining webinars.

 

Reference to any specific commercial products, process, service, manufacturer, or company does not constitute its endorsement or recommendation. Paid for by Kansas State University