Fresh Preserving Questions

We want to make the creation process even easier for you. So we’ve compiled the questions asked most frequently by thousands of consumers regarding fresh preserving. Our answers draw on our years of experience in the preserving industry. It’s our way of making sure your home preserved foods are the best they can be.

Why is it important to boil jars after filling them?

The most common reason for expiring food is a lack of a quality seal. The jar must go through the boiling step as a true seal only happens after the heating process when the can has cooled. This allows for stored food to remain fresh for up to 1 year.

Is it safe to pack fully cooked food into jars, adjust the caps and store it without additional heat processing?

The method of preserving you described is referred to as the open kettle method. Open kettle preserving is not a safe method to use. This method results in a high rate of food spoilage. Although the food is hot and may be fully cooked, it is difficult to reach and maintain the temperatures necessary to destroy spoilage microorganisms. If spoilage microorganisms are not destroyed, the food can spoil even though the cap is tightly closed.

Are there special steps to follow when preparing home preserving jars and lids for processing?

Yes, there are specific instructions for selecting, cleaning, and preheating jars, lids and bands prior to use. Always refer to the manufacturer’s instructions. If they are not available, this general information will help. Select home preserving jars that have no visible scratches, nicks, chips, or uneven rims. Examine lids to assure they are not scratched, have even and complete compound, and have not been used. Bands should be easy to slide on the jar, without any signs of warping or corrosion.

Wash jars, lids and bands in hot soapy water. Rinse well. Dry bands; set aside. Jars and lids must be preheated and kept hot until they are used. To preheat jars, completely submerge them in water that has been brought to a simmer (about 180°F). They should remain at this temperature until they are used, removing one at a time as needed. If jars are used for any recipe that is processed less than 10 minutes, the jar must be sterilized. To sterilize jars, submerge jars in water and boil 10 minutes. Allow sterilized jars to remain at a simmering temperature until they are used.

Can fruit be safely home preserved without the addition of sugar?

Yes, fruit may be preserved without sugar. Whether you have a dietary requirement, or a desire to make healthy eating choices, home preserving is a simple way to reduce the amount of sugar in your diet.

To can fruit without sugar, select fully-ripe, firm fruit at its peak flavor. Water or unsweetened fruit juice may be used in place of a sugar syrup. Prepare and process fruit as directed in recipe. Use only the Hot Pack method when preserving fruit without sugar.

Non-sugar sweeteners may be used as a replacement for sugar. For best results, add non-sugar sweetener just before serving preserved fruit. Spices, herbs and flavoring extracts can also be used to enhance the flavor of fruits being preserved without sugar.

Can vegetables be safely preserved without salt?

Yes, vegetables may be preserved without salt. The measure of salt called for in most vegetable recipes is too small to help prevent spoilage; it is there only for seasoning. To prepare vegetables with less or no salt, simply omit salt or reduce the amount of salt to taste. Do not omit or reduce salt from pickled foods or seafoods. Adding your favorite herbs or spices can easily enhance the flavor of vegetables.

Sometimes when preserving beets the color changes from red to pink or even white. How do I prevent color loss?

Leave 1 to 2 inches of the taproots and stems on the beets. Boil beets until the skins easily slip off. Drain beets. Remove skins and trim away the taproots and stems. Now, the beets should retain their distinctive red color when preserved . They may be preserved whole, sliced or diced.

How can I determine if the home preserving recipes received from friends and family are safe to use?

While you may have home preserving books or recipes considered to be family heirlooms or treasures, they may not always be safe to use. In 1989, the USDA updated their home preserving guidelines based on safety and quality. Therefore, a home preserving book or recipe that was published before 1989 may be outdated and could affect the safety and quality of your home preserved foods. Be sure the preserving book or recipe you use complies with up-to-date guidelines.

How do I determine what method to use?

To determine which method is appropriate for the food types you are preserving , refer to Preserving How-To. For up-to-date recipes indicating the correct processing time, see Recipes.

How do I know if a jar of home preserved food is spoiled?

When up-to-date guidelines, such as those outlined on this site, are followed exactly, there should be little concern about the quality and safety of your home preserved foods. As with commercial packaged foods, it is always wise to examine any food before using it. When you take it from the shelf, check each jar to see that it has retained a vacuum seal and that no visible changes have taken place during storage.

Unsealed lids indicate the possibility of spoilage. Spoilage produces gases that can break seals and/or cause the lids to swell. If a lid can be removed without the use of pressure to release a vacuum, do not use the product. Other signs of spoilage include mold, bubbling gases, cloudiness, spurting liquid upon opening, seepage, yeast growth, fermentation, sliminess or disagreeable odors. If you know that low-acids foods were improperly processed (i.e., in a boiling-water preserver as opposed to a steam-pressure preserver ) do not use them under any conditions.When cooked jams or jellies prepared with liquid fruit pectin do not set, how can they be fixed?

Before attempting to remake a jam, jelly or other fruit spread made with liquid fruit pectin, wait two weeks to determine if the product will gel. Not all recipes set within 24 hours. If after two weeks the product does not have a good set, it can be re-cooked in order to achieve a firmer texture.

Measure the unset product to be re-cooked. Prepare only a single batch at one time. For each quart of unset product, measure 3?4 cup sugar, 2 tablespoons lemon juice and 2 tablespoons liquid pectin, set aside. Place one quart of unset product into a medium saucepan and bring to boiling over medium-high heat. Quickly add the sugar, lemon juice and liquid pectin; bring to a rolling boil, stir constantly. Boil mixture hard for 1 minute. Remove from heat, skim foam if necessary. Carefully ladle hot mixture into hot jars, leaving 1?4-inch headspace. Adjust new lid and band on jar. Process in a boiling-water preserver for the full length of time indicated in the original recipe. If you suspect spoilage, dispose of the food without tasting it. Dispose of all spoiled foods in a manner that will prevent consumption by humans or animals.

How long can home preserved food be stored?

Food that has been properly preserved using an up-to-date tested recipe and that has a vacuum seal will keep indefinitely; however, over an extended period of time changes do occur. These changes may affect the flavor, color, texture and nutritional value of the product. For the highest quality, use home preserved food within one year.

How tightly should the bands be applied?

Using just your fingers, screw bands down evenly and firmly just until a point of resistance is met – fingertip tight. Do not over tighten bands by using the full strength of your hand or a utensil to screw the band down. Over tightening bands can prevent air from venting out of the jars, resulting in buckled lids or seal failure.

After processing, bands may appear to have loosened. This is normal. Do not retighten bands after processing since this may break the seal that is forming.

If home preserved foods have frozen during storage, are they safe to eat?

If the food was processed according to current home preserving recommendations, and the jars are still vacuum sealed, the food should be safe to eat. Examine jars closely – sometimes freezing can cause damage to the vacuum seal, or jar breakage. Home preserved food that has been frozen during storage may be less desirable due to changes in texture, flavor, nutritional value and color.

Is there a conversion for using the boiling-water preserver instead of a steam- pressure preserver when home preserving vegetables?

No, there is not a safe way to convert processing vegetables, meats, seafood and combination recipes from steam-pressure preserving to boiling-water preserving . Recipes in these categories are low-acid foods. The steam-pressure preserver is required to achieve the high temperature necessary to destroy microorganisms that can cause spoilage and illness.

I am following a low sodium diet. May I safely home preserve my pickle recipes with less salt?

Only fresh pack (or quick) pickle recipes may be safely adjusted to reduce salt. Reducing the amount of salt or omitting the salt from fresh pack pickle recipes will change the flavor and texture of the finished pickled product.

Salt is an important ingredient in fermented and brined pickle recipes. It should not be reduced or omitted when preparing this type of recipe.

What causes a lid to become corroded or rusted while it is on a jar of home preserved food?

Following the manufacturer’s instructions for preparing and using lids will reduce the possibility of corrosion. It is also important to use home preserving lids that have been stored in a cool, dry, dark place.

  • Not preparing lids for use according to manufacturer’s instructions;
  • Scratch in the enamel surface of lid;
  • Incorrect headspace;
  • Strong concentrations of salt or acid;
  • Improper storage of lids prior to canning;
  • Not removing bands before storing sealed jars;
  • Not wiping off lid and jar surface with a clean damp cloth to remove food particles and residue.

A jar of home preserved food with a lid that becomes spotted with rust may be used as long as it was properly processed using up-to-date methods, and there is a vacuum seal on the jar. Please note this applies to surface spots only.

What causes buckled lids?

Buckled lids appear to warp, bulge, or crease upward near the outer edge. Ball brand two-piece vacuum lids are made to release pressure by venting air from the jar after processing and upon cooling. When the lid does not vent, pressure build-up warps the lids and prevents a good seal.

There are several potential reasons for this to occur:

  • Applying the screw bands too tightly causes buckling that is apparent immediately after processing.
  • Boiling the lids softens the sealing compound too much, resulting in a premature seal.
  • Food spoilage due to incorrect processing produces gases inside the jar that force the lid to buckle or unseal.

Preventing buckled lids is simple. Always process foods using up-to-date guidelines, prepare lids according to manufacturer’s instructions, and apply bands just until a point of resistance is met – fingertip tight.

What causes color changes in home preserved foods?

Color changes typically result from the following:

  • How the produce is handled between harvesting and preserving;
  • Growing conditions for a particular season;
  • Overcooking or heating at too high a temperature;
  • Improper storage conditions;
  • Low sugar content in a recipe;
  • Quality of water used in recipe preparation, or
  • A reaction with the type of utensil used for cooking.

Following a reliable preserving guide such as the Ball Blue Book® of Preserving will give detailed information on how to avoid color changes in home preserved foods.

What causes jars to break during processing?

Home preserving jars are glass containers and therefore should be handled carefully. It is important to always follow the manufacturer’s instructions when preparing and using home preserving jars. It is also important to visually examine jars before use.

If jar breakage does occur, check the following points to determine if one of them is the cause:

  • Using commercial or old-style home preserving jars;
  • Using a metal utensil to remove air bubbles;
  • Using steel wool or a brush with a wire stem to clean jars;
  • Using a metal utensil to remove food for serving;
  • Handling and storing jars in such a way to cause scratching on the outside of the jar;
  • Placing hot food into a room temperature jar;
  • Placing a room temperature jar into boiling water;
  • Lifting a jar out of the preserver and placing it directly on a cool counter or a wet surface;
  • Using a processing method that is not approved for home preserving;
  • Abusive handling of a glass container.

What causes lids to come unsealed or not seal at all?

Using current home preserving jars, lids, bands, processing methods and times all help assure there is no seal failure or that unsealing does not occur. It is important to follow the manufacturer’s instructions when preparing jars, lids and bands for use. It is also important to examine the preserver to be certain it is in good working condition. When home preserving, always use an up-to-date, tested recipe from a reliable source.

If seal failure or unsealing does happen, check the following points to determine if one of them is the cause:

  • Insufficient or incorrect processing;
  • Over-tightening the band before processing or re-adjustment of the band after processing;
  • Incorrect headspace;
  • Reusing lids;
  • Using commercial jars;
  • Not preparing lids for use according to manufacturer’s instructions;
  • Not removing air bubbles from the jar or cleaning the rim of the jar before applying the lid.

If a lid does not seal within 24 hours after processing, the product must be

1. Reprocessed immediately, 2. Stored in the refrigerator and used within a few days, or 3. Placed in a proper freezer container and frozen.

To safely reprocess a product, remove the food from the jar. If it was hot-packed, reheat the food. Pack it into a clean, hot jar. Allow the correct headspace for the type of food being preserved. Place a new, pre-heated lid on the jar. Reprocess the product using the correct preserving method and follow the entire processing time as recommended by an up-to-date, reliable source.

What causes loss of liquid from jars during processing?

Loss of liquid from jars during processing typically result from the following:

  • Food not heated before packing into jars;
  • Food packed too tightly;
  • Incorrect headspace;
  • Air bubbles not removed before capping jars;
  • Steam-pressure preserver temperature allowed to fluctuate during processing;
  • Jars not covered with water in boiling-water preserver;
  • Jars removed from preserver too quickly after processing is complete;
  • Starchy foods absorbed liquid.

The food in the jar that is not covered by liquid may darken, but should not spoil as long as it was processed according to up-to-date methods and there is a vacuum seal on the jar. Do not open jar to replace liquid.

What is headspace? Why is it important?

The space in the jar between the top surface of the food or its liquid and the inside of the lid is called headspace. Leaving the correct depth of headspace is essential to achieve a strong vacuum seal.

If jars are overfilled, the contents may siphon or boil out during processing. Any food residue which then may remain on the jar rim, such as grease, juice, seeds or pulp can prevent the formation of an airtight seal.

When too much headspace is left, all the air may not vent from the jar during processing, preventing the formation of a strong vacuum seal.

The type of food being preserved determines the amount of headspace.

What processing methods are recommended for home preserved foods?

There are only two methods for heat processing home preserved foods that are considered safe: the boiling-water method for high-acid foods and steam-pressure method for low-acid foods. These methods are outlined on this site. See Preserving-How-To.

There is no substitute for adequate heat treatment for the correct length of time. Although some people may continue to use outdated methods, these practices are not safe and should not be used for any reason. If you have a recipe or instructions using a method not listed here, that information should be replaced with up-to-date recipes and guidelines.

What type of equipment should I look for if I’m just getting started in home preserving?

It is always best to use the type of home preserving jars and two-piece vacuum caps, boiling-water preserver and steam-pressure preservers that are described on this site. Ball® home preserving products have a wide variety of jar sizes and closures to make home preservers easy and safe. See Products.

Old jars and closures have a nostalgic appeal many people like; however, they are not considered the best type of jars and closures for home preserving. Jars requiring a zinc cap and jar rubber or jars requiring a glass lid, wire bail, and jar rubber have not been recommended since 1989. There is no definitive way to determine if a vacuum seal has formed. This is one reason why the two-piece vacuum cap is superior to older style closures.

Today there are only two recommended methods for safe processing of home preserved foods. When considering the type of preserver to use, follow the guidelines in Preserving-How-To.

Older style preservers may be functional, but they should be checked to determine if they meet today’s standards for processing foods. Particular attention must be given to steam-pressure preservers to assure their safety and accuracy. Refer to the manufacturer for more information on the use, safety and accuracy of older steam-pressure preservers.

Where is the best place to store home preserved foods?

The optimal location for home preserved foods to be stored is in an area that is cool, dry and as dark as possible. A temperature range of 50°F to 70°F is best. Food stored at temperatures higher than 70°F may lose some of its nourishing qualities. Freezing temperatures can cause the contents of a jar to freeze and expand, which in turn can break the seal or the jar.

Be certain the area you select to store your home preserved foods is a dry location. Damp locations can cause lids to corrode.

Since light hastens oxidation and destroys certain vitamins, a dark storage area is preferred. Light can also cause certain foods to fade in color. Placing filled jars in cupboards or boxes protects them from light.

Why do home preserved pickles lose their crunchy texture?

There are several factors that may cause a soft pickle:

  • Using a vinegar with an acidity level that is less than 5%;
  • Pickles were not processed or not processed long enough in a boiling-water canner to destroy spoilage microorganisms;
  • Variety of cucumber used;
  • Brine was too weak when fermenting cucumbers;
  • Cucumbers were not completely covered with brine while fermenting;
  • Cucumbers were not completely covered with liquid when packed in the jar;
  • Scum was not removed from top of brine while fermenting;
  • Improper storage or handling of cucumbers before pickling.

Why is it necessary to heat process home preserved foods?

"Processing" or "heat processing" home preserved foods is necessary to destroy all the microorganisms that could cause food spoilage and to vent air from the jar in order for a vacuum seal to form. Processing filled jars for the correct length of time, following approved guidelines will assure the product is safe to store on the shelf.

Why is it necessary to add bottled lemon juice or citric acid to some home preserved tomato recipes? Must the lemon juice be bottled lemon juice?

Tomatoes have a pH (acid) level that is just above the line dividing high-acid foods and low-acid foods. It is important for the safety and quality of tomato recipes that the proper acid level is maintained. Since many factors can decrease the natural acidity in tomatoes, the addition of bottled lemon juice or citric acid helps ensure the correct acidification. Bottled lemon juice must be used because its acid level is consistent, unlike fresh lemons.

Recipes that include an adequate amount of vinegar (5% acidity) do not require additional acidification, such as salsa, tomato chutney, and pickled tomatoes.

Always follow a tested recipe. Do not alter the type of ingredients in the recipe or the amount used. For up-to-date recipes, see Recipes.

How do I check to ensure my soft spread made without the use of commercial pectin will form a gel?

There are three tests you can perform to ensure your soft spread made without the use of commercial pectin has reached the gel stage.

Temperature Test Cook the soft spread until it reaches a temperature of 220°F, or 8°F above the boiling point of water. Measure the temperature of soft spreads with a candy or jelly thermometer. Always insert the thermometer vertically into the soft spread and ensure that it does not contact the surface of the pot.

Sheet Test Dip a cold metal spoon into the boiling soft spread. Lift the spoon and hold it horizontally with edge down so that the syrup runs off the edge. As the mixture cooks, the drops will become heavier and will drop off the spoon separately but two at a time. When the two drops join together and "sheet" off the spoon, the gel stage haven reached.

Refrigerator Test Chill two or three small saucers in the freezer. Place a teaspoonful of soft spread on the chilled saucer and place in the freezer for 1 minute. Remove the saucer from the freezer and push the edge of the spread with your finger. A mixture that has reached the gel stage will be set, and the surface will wrinkle when the edge is pushed. Note: To prevent overcooking or scorching, remove the soft spread from the heat before performing this test.

If the test you performed shows that the gel stage has not been reached, return the mixture to the heat to cook for a few minutes longer, then retest the soft spread.

Why are our preserving lids no longer gold?

The Ball® Preserving Lids have a new brushed silver look this year. The new look matches today’s kitchens that have more stainless steel and polished nickel finishes. Although the design has changed, the trusted quality you expect is still the same. We continue to craft quality preserving lids with our time-tested sealing compound, just as we have for many generations.

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