Summer's bountiful harvest also brings a crop of questions about canning and freezing. Be sure you are up on the latest recommendations from the U.S. Department of Agriculture and your state extension service.
QUESTION - I've just moved from Illinois to Colorado. Does the higher altitude affect processing times?ANSWER - Yes. Most processing times and temperatures are for altitudes of 1,000 feet above sea level or lower. For boiling-water canning, you must use a longer processing time. For pressure canning, the processing times remain the same but higher pressures are used. Call your local county extension agent for detailed instructions for your area.
QUESTION - My neighbor says pickles should be processed. Is she right?
ANSWER - Yes. Pickles should be packed in sterilized standard canning jars with standard lids and processed in a boiling-water canner. This destroys organisms that can cause spoilage and inactivates enzymes that affect flavor, color and texture.
QUESTION - I'd like to can tomatoes without salt. How can I be sure they'll keep?
ANSWER - It's heat processing, not the salt, that keeps tomatoes or any other food from spoiling. For salt-free tomatoes, just omit the salt from your recipe and process in a boiling-water canner for 35 minutes for pints, 45 minutes for quarts. You also can make salt-free tomato juice, tomato juice cocktail or stewed tomatoes. Do add 1 tablespoon lemon juice to each pint jar or 2 tablespoons to each quart jar of any canned tomato product for correct acidity.
QUESTION - How do I can fruits without sugar?
ANSWER - To can fruits without sugar, use firm, fully ripe fruit. Cook the prepared fruit in a small amount of water until hot. Pack hot fruit into hot jars and add enough boiling water or boiling unsweetened fruit juice to cover. Adjust lids and process as recommended for that fruit.
QUESTION - Can I use pectin left over from last year?
ANSWER - For best results and proper gelling, always use fresh pectin. Look for a manufacturing date on the package; powdered pectin is good for one year after that date.
QUESTION - How should I adjust a liquid-pectin recipe to use light pectin?
ANSWER - Liquid, powdered and light pectins differ somewhat in the way they are used. Be sure to read and follow the directions on the package exactly. Do not substitute one type of pectin in a recipe designed for another type. For answers to many jelly-making questions, call the toll-free number on the pectin package.
QUESTION - I like to make jam a few jars at a time. Please tell me how to process them in my microwave oven.
ANSWER - You may use your microwave to heat water to boiling quickly or for cooking fruit mixtures for jam, jelly, or preserves, or for vegetable mixtures for relishes or pickles. However, do not attempt to process in the microwave oven. Because of uneven heating patterns, the food may not be uniformly heated to a temperature high enough to kill bacteria.