Remedies for Canning Problems

Fruits and Vegetables

ProblemCausePrevention
Loss of liquid from glass jars during processing (not a sign of spoilage).
(Do not open to replace liquid.)
1. Lowering pressure in canner suddenly after processing period.1. Do not force pressure down by placing canner in a draft opening the petcock too soon, etc. Allow pressure to drop to zero naturally; wait two minutes before opening.
2. Fluctuating pressure during processing in pressure canner.2. Maintain a constant temperature throughout processing time.
3. Failure to work out air bubbles from jars before processing.3. Remove by running a bubble freer between food and jar.
4. Improper seal for the type closure used.4. Follow the manufacturer’s directions for closure used.
5. Jars not covered with water in water bath canner.5. Jars should be covered with 1 to 2 inches of water in canner throughout processing period.
6. Starchy foods absorbed liquid.6. None.
7. Insufficient head space.7. Leave recommended space.

Imperfect seal (discard food unless the trouble was detected within a few hours).1. Chips or cracks in jars.1. Examine carefully by rubbing finger around the mouth of the jar.
2. Failure to follow recommended directions for closures used.2. Follow manufacturer’s directions.
3. Particles left on mouth of jar.3. A clean, damp cloth should be used to remove any seeds, seasonings, etc., that prevent a perfect seal.
4. Using old closures that should be discarded.4. Do not reuse rubber rings and self-sealing metal lids. Do not use rusty bands.
5. Lifting jars by tops or inverting while hot.5. Use tongs for removing jars from canner or grasp below lip. Leave in upright position.

Product dark at top of jar (not necessarily a sign of spoilage).1. Air left in the jars permits oxidation.1. Remove air bubbles before sealing jars. Use recommended head space.
2. Insufficient amount of liquid or syrup.2. Cover product with water or syrup.
3. Food not processed long enough to destroy enzymes.3. Process recommended length of time.

Cloudy liquid (sometimes denotes spoilage).1. Starch in vegetables.1. Select products at desirable stage of maturity. Do not use overmature vegetables.
2. Minerals in water.2. Use soft water.
3. Fillers in table salt.3. Use pure refined salt.
4. Spoilage.4. Process by recommended method and for recommended time.

Color changes that are undesirable.1 . Contact with minerals, such as iron, zinc, or copper in cooking utensils or water.1. Avoid these conditions by using carefully selected cooking utensils. Use soft water.
2. Overprocessing.2. Follow directions for processing time.
3. Immature or overmature product.3. Select fruits or vegetables at optimum stage of maturity.
4. Exposure to light.4. Best to store canned foods in a dark place.
5. May be a distinct spoilage.5. If any ”off” odor or spoilage is suspected, discard food and sterilize or destroy jar.
6. Natural and harmless substances in fruits and vegetables.6. None.

Floating (especially some fruits).1. Overprocessing fruits and tomatoes destroys pectin.1. Follow directions for processing time.
2. Fruit is lighter than syrup.2. Use firm, ripe fruit. Heat before packing. Use a light to medium syrup.
3. Improper packing.3. Pack fruit as closely as possible without crushing it.

Spoilage.1. Incorrect pressure.1. Gauge should be checked every year for accuracy.
2. Overpacking.2. Jars should be well filled, but not packed.
3. Incorrect timing.3. Follow directions for timing.
4. Incorrect method used.4. Low acid vegetables and meats must be pressure canned for safety.
5. Poor selection of fruits and vegetables.5. Select product of suitable variety and at proper stage of maturity. Can immediately after gathering.

Juices

Problem Cause Prevention
Fermentation or spoilage.1. Failure to process adequately.1. Juices should be processed in boiling water bath (212° F.).
2. Imperfect seal.2. Use recommended methods and processing time. Use perfect jars and fittings.
3. Air left in jars.3. Proper processing will exclude air from jars.

Cloudy sediment in bottom of jar.1. Solids in juice settle.1. Juice may be restrained and made into jelly. Shake juices if used as a beverage.

Separation of juice (especially tomato).1. Enzymatic change during handling (after cutting).1. Heat tomatoes quickly to simmering temperature.

Poor flavor.1. Immature, overripe or inferior fruit used.1. Use only good-quality, firm, ripe fruit or tomatoes for making juice.
2. Use of too much water for extracting fruit juice.2. Use only amount of water called for in directions. No water is added to tomatoes.
3. Improper storage.3. Cool, dark, dry storage.