20 Most Common Food Preservation FAQs That You Need to Know

Food preservation seems like a fun activity, especially if you have tons of fruit or vegetables that are at risk of going bad. Instead of risking the process going badly, take a look at some common food preservation FAQs people want to know about.

If you don’t know how to do it right, your food can spoil quickly and you may even be at risk of infection or disease.

Don’t worry, though, there are some things to keep in mind when canning and preserving food safely.

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These are the top food preservation questions

FAQ #1: When picking jars, is the head-space really important?

One of the key parts in canning is leaving the correct amount of head-space in the jar to create a vacuum seal. When there isn’t enough head-space, the food can expand and bubble out.

This is a sign of air trying to escape from under the lid. If there are bubbles, a deposit on the seal can occur, preventing the jar from sealing completely.

Finally, if there is too much head-space left, the jars may not seal and the food at the top will discolor.

FAQ #2: How long can canned food be stored?

If the food has been preserved correctly, it can last up to one year. Keep in mind, that the food has to be stored in a dry and cool place.

Never keep your canned food in a warm place with direct sunlight, near a furnace, or hot pipes, as this will cause your food to lose its quality within a few weeks or months.

If the place is too warm, moisture can corrode the metal lids or bands on your jars, which causes leakage and spoil the food.

FAQ #3: Do I need to sterilize the jars before processing?

You don’t need to sterilize your jars if you plan on processing them in a pressure canner.

Another reason to not sterilize is if you will fill them with food and then process them in a boiling water bath canner for 10 minutes or more.

Despite this, it is recommended to take the extra time to sterilize the cans and not take any risks.

When the jars are processed in a boiling bath for less than 10 minutes, they do need to be sterilized. To do this, simply boil them in hot water for 10 minutes before you fill them.

FAQ #4: Is it safe to use the oven for food processing?

The oven is not a safe tool to process your food because the temperature will vary and it depends on the accuracy of the oven regulators and the heat circulation.

By the way, dry heat penetrates the jars of food too slowly, causing them to possibly explode inside the oven.

FAQ #5: Why do you need to exhaust a pressure canner?

If the pot hasn’t been exhausted, the temperature inside may not match the pressure on the gauge. Before closing the valve, allow the steam to escape for 10 minutes.

FAQ #6: Should liquid lost during processing be replaced?

In this case, the loss of liquid doesn’t cause spoilage, however, the food above the liquid may become a bit darker.

FAQ #7: Is it all right to reuse jar bands and lids?

You can plan to reuse screw bands unless they are rusted or the top edge is pried up, which will prevent a proper seal.

Lids should never be reused because the sealing compound becomes indented after the first use, and so it won’t create an airtight seal.

FAQ #8: Is it safe to use the canning method for an open kettle?

In an open kettle, the food is cooked with an open pot, then packed into hot jars, and sealed without processing.

Still, the temperatures obtained are not hot enough to destroy all the microorganisms in the food. Contamination may happen as well when transferring food from the kettle to the jars.

FAQ #9: What causes the undersides of jar lids to discolor?

There are natural compounds in some products, especially acids that corrode the metal and cause dark deposits to appear on the underside of the jar lids.

While the deposit is harmless if the jars have been properly processed, the jar must have a good seal.

FAQ #10: Why do jars break down during processing?

There are many reasons for jars breaking down. Some include the following:

  • The jars are filled with unheated or raw food while they are in boiling water in the canner. The rapid change in temperature causes the jars to crack.
  • Using commercial food jars
  • Putting hot food in cold jars
  • Using jars that have chips or cracks on them
  • Jars bump against each other during the canning process
  • The jars are placed directly on the bottom of the canner and not on a rack.

FAQ #11: Can hard water scale or film be removed from canning jars?

You can do this by soaking the jars for several hours in a solution made of 1 gallon of water and 1 cup of vinegar.

These are all just some questions on the general canning and food process, but you surely have specific doubts about fruits and vegetables.

These are the top food preservation FAQs on fruits and vegetables:

FAQ #12: Is it safe to preserve food without salt?

You can preserve food without any addition of salt. The salt is mostly used for flavor and not for preventing spoilage.

FAQ #13: Is it safe to preserve fruits without sugar?

The sugar, in this case, is added to help retain the shape of the fruit, to improve the flavor, and to help stabilize the color.

While the sugar isn’t added as a preservative, it is a good way to keep flavor and color.

FAQ #14: If aspirin is used, can vegetables and fruits be canned without heating?

Aspirin shouldn’t be used for preservation because it isn’t reliable in creating a satisfactory product or preventing spoilage.

Using adequate heat treatment is considered the only safe procedure for preserving fruits and vegetables.

FAQ #15: If vinegar is used, is it safe to can green beans in a boiling water bath?

It is never recommended to shorten processed times, even if vinegar is used for preserving fresh vegetables.

FAQ #16: Should I precook all vegetables before canning?

For higher quality, it is best to precook vegetables. Nonetheless, some vegetables can be packed cold or raw in jars before they are processed in the pressure canner.

FAQ #17: What vegetables expand rather than shrink during processing?

Starchy vegetables, including Lima beans, corn, and peas, will expand during processing, so they should be packed loosely.

FAQ #18: What makes corn turn brown during canning?

Browning often occurs when the temperature is too high, which causes the sugar to caramelize. Some of the minerals in the water used for canning can also cause browning.

To finish, let us tell you the main factors to take into account when you are trying to preserve meat, which may seem difficult, but it can be safe and tasty in the long run.

These are the top FAQs on canning meat:

FAQ #19: Is it safe to can poultry and meat without salt?

As with vegetables, salt is only used for flavoring, so it isn’t necessary for the safe processing of your meat.

FAQ #20: Should chicken giblets be canned in the same jar with chicken?

You shouldn’t place chicken giblets in the same jar as the chicken, as their flavor may alter and penetrate the other pieces of chicken in the jar.

After reading these food preservation FAQs, you are now ready to start preserving and canning at home! Soon, you’ll be an expert in the matter.