Canning Vegetables - Care must be taken when canning vegetables to maintain color, texture and taste, and to ensure safety. Always use high quality produce for the best canned vegetables. Thoroughly clean all produce, tools, jars, and utensils prior to canning.
The USDA has determined that when canning vegetables, with the exception of some tomato products having a high enough acid content, the home-canner must use a pressure canner to ensure safety. Old recipes calling for water-bath processing must no longer be used unless adapted for pressure canning. All processing times must be adjusted for elevations above 1,000 feet above sea level.
Blanching Vegetables to Preserve Color
Canning vegetables should be blanched, or cooked briefly, before packing into the jars to help maintain color. Blanching also removes air from the vegetables allowing for a tighter pack and reduces floating. Vegetables that float above the liquid level may oxidize and darken during storage (still safe to eat but not as "pretty").
Canning vegetables should be blanched in gently simmering water and not a rapid boil. A small amount of lemon juice or baking soda added to the water before blanching will help vegetables to maintain their bright color. Here is a link to the Blancher sold at CanningPantry.com.
Canning Vegetables Using Hot Pack Verses Raw Pack Methods
Blanching vegetables as discussed above is used in the hot pack method. This results in a tighter pack, better color and less floating. The hot pack method is strongly recommeded for the best quality canned vegetables. After blanching, pack the hot vegetables into clean, hot jars, leaving 1-inch of headspace. Cover the vegetables completely with the hot cooking water, maintaining the 1-inch of headspace. Wipe the jar rims and threads with a clean cloth, apply the hot lids and rings and process the jars in a pressure canner for the recipe-specified time and pressure.
The raw pack method is when unheated vegetables are packed directly into the hot jars without pre-cooking or blanching. This method may be used for delicate vegetables such as summer squash, that would not maintain their shape if cooked first. Other handling procedures are the same as with the hot pack method.
Canning Vegetable Safety
With the exception of meats, fish, and poultry, there is a greater risk of food poisoning with home canned vegetables than any other home canned food. Care must be taken during each phase of canning to ensure proper methods are followed. Home canned vegetables must be processed in a pressure canner at the pressure and time specified in the recipe, adjusting for elevations above 1,000 feet above sea level.
Always store canned vegetables in a cool, dry, dark location. Warm locations can result in food expansion and failure of lid seals, leading to dangerous food spoilage.
Following the above procedures when canning vegetables, will result in high-quality canned products that are safe to eat and that you can be proud of.