How to prevent problems in canning

Yield: 1 Servings

Measure Ingredient


There are so many factors involved in canning that sometimes things can go wrong. Here are some common problems, causes, and solutions.

SPOILAGE: Spoilage is caused by improper handling, faulty seals, or under processing. Follow all directions carefully and use the proper equipment and the right king of food as directed in the recipes. The signs of spoilage are: bulging lids, broken seals, leakage, changes in color, foaming, unusual softness or slipperiness, spurting liquid when jars are opened, mold, and off odor. If you notice any of these signs, don't use the food. Discard it where humans and animals won't be able to get to it. You can salvage the jars by washing them well, rinsing, and then boiling them for 15 minutes.

LOSING LIQUID: Jars can lose liquid during processing because the food was not hot enough before packing; because the jars were filled too fill and liquid boiled out; because air bubbles were not released; because the jars weren't covered with boiling water during the boiling water bath processing; because pressure fluctuated during steam pressure processing; because you tried to hurry the pressure reduction and liquid was forced out of jars by the sudden change in pressure; or because starchy food can absorb liquid during processing. Don't try to add more liquid to the jars, the food is safe as it is. If you add more liquid, you must put food in clean, hot jars, seal with new lids, and reprocess.

UNDER PROCESSING: Under processing can be caused by skimping on processing time, not having an accurate gauge on your pressure canner, not reducing the canner pressure as the manufacturer directs, or not following head space guides, especially for foods like corn, peas, or lima beans, which expand a great deal during processing.

JARS THAT DON'T SEAL: Jars that don't seal could be the result of flaws in the jar or lids, inadequate heat, excess air in the jar, or food on the rim of the jar. the seal could have been broken by tightening the screw band after removing the jar from the canner or by turning the jar over as it's removed from the canner, or by leaving too much or too little head space in the jar, or by failing to release air bubbles before sealing. Foods in jars that don't seal can be repacked immediately in clean jars with new lids and reprocessed. Or, if just a jar or two fail to seal, refrigerate the contents of these, and use as quickly as possible.

CLOUDY LIQUIDS: Cloudy liquids inside jars do not necessarily indicate spoilage; they may be the result of minerals in the water, starch in the vegetable, or fillers added to table salt. But if canned foods show any signs of spoilage, discard them.

FLOATING: Vegetables that float in cold packed jars can be the result of overcooking or of too few vegetables for the amount of liquid.

Check carefully for other signs of spoilage.

DISCOLORATION OF FOOD: Discolored food in jars may mean the jars have not been filled full enough (air at the top of the jar causes the food to darken), or that processing time wasn't long enough to destroy enzymes. Iron or copper in the water or storage in light can also cause discoloration. Green vegetables may lose their bright color during processing through the natural reaction of heat breaking down the chlorophyll; but they're still all right to eat.

Some green vegetables may turn brown from overcooking or because they were too ripe to be canned. Yellow crystals on canned green vegetables are due to glycoside, a natural and harmless substance.

White crystals on spinach are also natural and harmless. Some foods may turn a blackish brown or gray from natural chemical substances such as tannins, sulfur compounds, and acids reacting with hard water, copper, iron, or chipped enameled utensils. Some varieties of corn and over mature or over processed corn can also discolor. Color changes don't always mean that food has spoiled, although spoiled food may be discolored. Check for other signs of spoilage.

DISCOLORED LIDS: The underside of the jar's lid may discolor from chemicals in the food or water. This is common and represents no danger.

BREAKING JARS: Jars that break in a canner may have had hairline cracks before they were filled, or may not have been hot enough. the jars may have bumped each other during processing, or were placed directly on the bottom of the canner without a rack.

SCUM OR MILKY POWDER ON JAR OUTSIDE: A scum or milky powder on the outside of jars, noticeable after processing or cooling, is due merely to minerals in the water. Wipe it off with a cloth and don't worry about it. Next time, add a tablespoon or two of vinegar or a teaspoon of cream of tartar to the ~~~ # VbReader V1⅖ #Are cats really intelligent aliens taking overearth?

~-- xMail/beta * Origin: Mike's Mansion (503) 760-3777 Portland,OR (1:105/81) SEEN-BY: 270/101 280/1 396/1 3615/50 51 3651/2 7 9 13PATH: 105/81 330 270/101 396/1 3615/50 3651/13 9 7 Area: COOKING Date : Oct 04 '95, 08:58 Scn From : Dorothy Flatman 1:105/81.0 To : All 1:3651/7.0 Subj : Canning CR 8/79


TID: xMail 1.01.0324 001241-048 MSGID: 1:105/81 0724fc69 EID: 1da9 f4459719

Similar recipes