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Tag: Food Preservation

Color Changes in Home Canned Foods

Posted on by Karen Blakeslee
beets
Pale diced beets
Photo: K-State Research and Extension

Pink, red, blue or light purple discoloration sometimes occurs in home canned apples, cauliflower, pears, peaches or beets.

Keep all produce cool after harvest. When using the hot pack method, do not overcook or heat to too high a temperatures. Excessive heat changes natural food pigments. Use correct processing methods and time to reduce discoloration. Pressure canning can be used to can pears. But it can cause pink discoloration in canned pears. Water bath processing is a better method.

If the fruit grew in dry weather, it often turns pink and cannot be prevented.  While the color doesn’t look right, the pears are safe to eat.

Other foods may have color changes. Garlic can become greenish or purple if it is immature or not completely dry before canning. Red beets may lose color if overcooked before canning or over-processed.

Sources: https://nchfp.uga.edu/how/can_02/pear_halved.html and  https://extension.umn.edu/preserving-and-preparing/food-preservation-and-canning-troubleshooting-guide

 

Updated Electric Water Bath Canner

Posted on by Karen Blakeslee
Photo: ballmasonjars.com

Looking for an alternative to stovetop water bath canning? Newell Brands, makers of Ball® products, has updated their electric water bath canner. The new version is called the Ball® EasyCanner.

This is a freestanding appliance and can be used for any water bath canned recipes. It is not a pressure canning appliance. It features some technology to help make water bath canning easier. The user must add time to adjust for elevation.

It holds up to 8 pints or 7 quarts. The rack is a bit bigger than the previous model. This appliance can also be used for cooking a meal, soup, or serving a hot beverage. It features a spigot to drain water or dispense other liquids.

Learn more at ballmasonjars.com website. It is now available from  major retailers.

 

Sunscald on Vegetables-Safe for Canning?

Posted on by Karen Blakeslee
Sunscald on onions
Sunscald on onions
Photo: Michigan State University ANR Communications Flickr

Despite best efforts, garden produce may develop a physiological disorder called sunscald. Is this produce safe for food preservation? It depends.

When light-colored areas appear on produce surfaces exposed to direct sunlight, these areas can change colors, turn dry, papery, and wrinkled. This damage can cause fungi to invade the food and cause rot.

When choosing produce to preserve, it is strongly recommended to use the best produce possible for the safest results. Damage such as sunscald could change the acidity of the food. Simply cutting away the damage may not remove the contamination. Fungi can grow deep into the food.

If light damage is present, no contamination has developed, the damaged areas could be removed. Freezing the remainder may be the best option.

Source: Kansas Garden Guide

 

Make Time for Food Preservation

Posted on by Karen Blakeslee
Photo: K-State Research and Extension

Gardens are bursting with fresh produce and many gardeners are also rushing to preserve the bounty to enjoy later. But rushing the steps of food preservation can lead to problems in the end. Keep these tips in mind:

  • Avoid starting food preservation if you cannot finish it in the same timeframe, especially in the evening. This can lead to quality and safety problems.
  • Get others to help! This can make food preservation more enjoyable and less stressful. Assign tasks appropriate for children. This can also encourage them to eat what they help preserve.
  • Make sure you have all the tools, equipment, and ingredients needed for the recipe you intend to preserve.
  • Set up the work flow to help with efficiency. This will also help you discover missing ingredients or equipment.
  • Clean as you go!

 

Canning Previously Frozen Tomatoes

Posted on by Karen Blakeslee

So you saved your tomato crop in the freezer. Can those frozen tomatoes be canned?

It is not recommended to can tomatoes that froze on the vine. This is because the acid content changes too much, while on the vine, making them unsafe for canning.

But tomatoes harvested prior to a fall freeze, then frozen, do not change in acidity. What does change is their texture and how they measure.

The best choice for canning previously frozen tomatoes is to make a well cooked product such as a stewed or crushed tomato product, or made into tomato juice or sauce.

It is not recommended to can them whole or quartered. They will pack into the jars differently, absorb moisture differently, and the heat transfers through the jars differently. This could lead to under processing and spoilage. Tomato canning recipes are based on fresh tomatoes.

Source: University of Georgia

 

Fresh Lemons vs. Bottled Lemon Juice for Canning

Posted on by Karen Blakeslee
lemon juice
Use bottled lemon juice in all canning for safest results.
Photo: Canva.com

Whether adding lemon juice to tomatoes to acidify them safely or adding lemon juice to a jelly or jam, the best and safest choice is bottled lemon juice. Here’s why.

Bottled lemon juice is standardized, or uniformly acidified, per FDA regulations. Therefore, it is consistent which provides a known level of safety for food preservation. The final acidity of a food product is critical to deter the growth of microorganisms that can cause spoilage or foodborne illness.

Fresh lemons, however, have an inconsistent acid, or pH, level. This can vary within the same variety of lemons, but also vary due to maturity, growing conditions, soil, fertilizer, rootstock, and storage conditions. While safe to eat fresh for a great meal, they are not the safe choice for food preservation.

As a reminder, when canning tomatoes, they must be acidified by using bottled lemon juice, citric acid, or vinegar with 5% acidity. Here are the choices and recommended usage levels:

  • Bottled Lemon Juice
    1 tablespoon per pint
    2 tablespoons per quart
  • Citric acid
    1/4 teaspoon per pint
    1/2 teaspoon per quart
  • Vinegar with 5% acidity
    2 tablespoons per pint
    4 tablespoons per quart

Sources: Iowa State University AnswerLine and K-State Research and Extension

 

Choosing Vinegar for Pickling and Canning

Posted on by Karen Blakeslee
vinegar
Photo: KSRE RRC

First step, read the label. Look for vinegar that is 5% acidity.

Today’s recipes, including Extension and USDA food preservation recipes, use vinegar that has 5% acidity. Not all vinegars are the same. They range from 2.5% to more than 6%. Therefore it is important to read the label or ingredient statement to verify the acidity level.

The National Center for Home Food Preservation at the University of Georgia gives these recommendations if you have used a vinegar with  less than 5% acidity.

  • If your canned food has been preserved for less than 24 hours using 4% vinegar, it is advisable to store the jars in the refrigerator to maintain the safety and quality of the product.
  • If your canned food has been preserved for more than 24 hours using 4% vinegar, it is advisable to discard the product.

 

Check Canning Lids for Defects

Posted on by Karen Blakeslee
lid defect
Uneven sealing compound
Photo: courtesy Susan Stich

Canning lids are essential for canning food. When preparing lids to use, take a look at them to be sure they are in good condition to reduce problems after canning.

Always used new lids, never reuse canning lids as the rubber seal is already indented and the lid was likely bent when removing it from the jar.

Wash new lids in hot, soapy water. That’s it! Do not boil them as that step is no longer required. Boiling the lids can lead to seal failures.

Look at the underside of the lid. Defects can happen, such as the irregular sealing compound on the lid in the picture. This can lead to seal failures. Contact the manufacturer to report the problem.

 

Jam and Jelly Problems and Solutions

Posted on by Karen Blakeslee
peach jam
Source: NCHFP
Photo: KSRE RRC

Sometimes jam and jelly recipes just don’t turn out right. So here are some problems, causes, and prevention strategies.

Learn more about other problems and solutions for jam and jelly at https://nchfp.uga.edu/how/can_07/jellyproblems.html

 

PROBLEM CAUSE PREVENTION
Too soft Overcooking fruit to extract juice Avoid overcooking as this lowers jellying capacity of pectin
Used too much water to extract juice Use recommended amount
Incorrect amounts of sugar and juice Measure correctly
Undercooking jam or jelly mixture Follow cooking times exactly
Insufficient acid Lemon juice may need to be added
Making too large of a batch Make only one recipe at a time
Moving finished jars too soon Allow finished jars to sit at least 12 hours
Insufficient time before using Some fruits take up to 2 weeks to set completely

A Caution About Preserving White Peaches

Posted on by Karen Blakeslee

It’s almost peach season and many will be preserving this summer favorite in various tasty treats.

White fleshed peaches, however, cannot be canned like yellow peaches. White peaches are low acid so traditional canning cannot be done, and that includes water bath canning and pressure canning. No research has been done for safe canning. This includes plain peaches, jam, jelly, or any other mixture.

The best option is to freeze white peaches or eat them fresh.

To preserve yellow peaches, see our Preserve it Fresh, Preserve it Safe: Peaches publication.

Source: University of Georgia

 

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