Canning and preserving is a science and, like any science, you must be precise when working in your lab, which in this case, is your kitchen. Although you follow your recipe instructions to the letter, accurately measure your ingredients, and properly process your filled jars, you aren't guaranteed a perfect product.
Your jars didn't seal properly
There may be several reasons your jar didn't seal after processing: Maybe you didn't follow the manufacturer's instructions for using the jars and two-piece caps; maybe a particle of food was left on the jar rim; maybe a piece of food was forced out of the jar during processing; maybe the processing timing was calculated incorrectly; or maybe your filled jars weren't covered by 1 to 2 inches of water in your water-bath canner.
Eliminate these problems by reviewing and following the manufacturer's instructions for preparing and using your jars and two-piece caps, cleaning the rims after filling your jars, leaving the proper headspace in the jar, timing your processing after reaching a boil or the correct pressure, and covering your filled jars with 1 to 2 inches of water in your water-bath canner.
But what if your jar seals and then comes open? If this happens, check for hairline cracks in the jar. If you find a crack in the jar, discard the food (just in case there's a piece of glass in it) and the jar. If your food wasn't processed correctly, microorganisms may be active. They'll produce a gas in the jar that expands and forces the seal to break loose. Because this indicates food spoilage, don't taste the food or use it; dispose of it properly.
Your jar lost liquid during processing
Starchy food absorbs liquid — this is normal, and there's no way to correct it. Raw, unheated food also absorbs liquid during processing. Eliminate liquid absorption by using the hot-pack method.
Trapped air bubbles released during processing increase the air space in the jar while lowering the liquid level. Always release air bubbles before sealing and processing your jars.
Longer-than-suggested processing times cause a loss of liquid in your jars. If you're water-bath canning, prevent this by covering your jars with 1 to 2 inches of water for processing. If you're pressure canning, keep the pressure constant during processing; then, let the pressure drop to 0 and wait 2 minutes before opening the canner.
Your jar's liquid is cloudy
Cloudy liquid occurs from using water with lots of minerals, salt containing additives, or ground spices. Remedy these problems by using soft water, pure salt (like canning and pickling salt), and whole spices.
If you didn't use one of the items mentioned in the previous paragraph and your jar's liquid is still cloudy, you probably have spoiled food. Dispose of it without tasting it.
Your jar's lid has dark spots on the underside
Occasionally, naturally occurring compounds (like acids and salts) in some food cause a brown or black deposit, along with some corrosion, on the inside of the lid. This deposit is harmless and doesn't spoil your food.
Your jelly doesn't have the right consistency
Although you can't fix a batch of jelly that didn't set up or is too stiff, you may safely eat your jelly. Review the following tips to avoid future problems:
- Soft, runny, or syrupy jelly: The proportions of sugar, acid, and juice may not be correct. Accurately measure your ingredients.tabmark
- Work with smaller amounts of juice, no more than 4 to 6 cups at one time. Working with larger amounts of juice won't allow the juice to heat fast enough to reach its gel point, which can result in runny jelly.
- Store your sealed jars in a cool, dark place with a temperature between 50 and 70 degrees. Jelly may break down (become runny) in less-than-ideal storage conditions.
On the other end of the spectrum, stiff jelly results from using too little sugar or cooking the jelly too long before it reaches the gel point. When your recipe doesn't call for adding pectin, your proportion guideline for sugar and juice (for most fruit) is 3/4 cup of sugar to 1 cup of fruit juice.
Your jelly is cloudy or has bubbles
There's no solution for fixing cloudy jelly, but rest assured, it's safe to use. Poor straining is the most common cause of cloudy jelly. Carefully strain your fruit through a damp jelly bag (or cheesecloth). This keeps pulp out of the juice. Don't squeeze the jelly bag; let it drain slowly by gravity.
Overcooking fruit breaks down fruit pulp. And broken pulp is small enough to pass through your strainer. Be sure to cook your fruit just until it's tender.
And finally, don't allow your jelly to cool before filling your jars.
 | Although cloudy jelly isn't anything to worry about, moving bubbles in jelly indicates spoilage. This occurs when living microorganisms in the jar break the vacuum seal during storage. Discard your food without tasting it. Review the step-by-step instructions for preparing your food, readying and filling your jars, and processing your food. (Note: It's not uncommon to see a few small air bubbles lodged in a thick jam or butter. It's the moving bubbles you need to be concerned with.) |
Your jelly has mold on it
Mold on your jelly indicates an improper or a broken seal. Don't use or taste the jelly — just throw it out. Always clean your jar rims, allow the proper headspace, and process your jars for the correct amount of time.
Your jelly has very little fruit flavor
Jelly with weak flavor results from using fruit that's not ripe or fruit that's been stored too long after being picked. You can't add flavor to your jelly, but the next time, use tree-ripened fruit; store your sealed jars in a cool, dark, dry location; and consume your jelly within one year.
Your pickle jars have white sediment in the bottom
Soft pickles in a jar with white sediment indicate spoilage. Don't taste these, simply discard them.
But, if the pickles are firm, they're safe to eat. The sediment is a harmless lactic acid or yeast that develops in the jar and settles to the bottom.
Your food floats in the jar
Fruit weighs less than the syrup you pack it in. If your fruit isn't packed snuggly, it'll float to the surface. Use ripe, firm fruit, and pack it tightly — but don't crush it. Fill your jars with a light to medium syrup. You can't sink floating fruit, but with practice, you can improve your packing skills.
Raw-packed vegetables shrink during processing. This doesn't indicate food spoilage. Reduce shrinkage by packing your vegetables tightly or blanching or precooking them prior to packing them in the jars.
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