Can green beans using a pressure canner, which reaches temperatures of over 240 degrees Fahrenheit and effectively kills botulism spores. Due to the vegetable's low acidity level, it is unsafe to can green beans using the water-bath canning method. Simply Canning offers a recipe for pressure-canned green beans that calls for 9 or 14 pounds of fresh green beans, depending on whether your pressure canner loads quart-sized or pint-sized jars.
To make Simply Canning’s canned green beans, select fresh plump beans to the desired weight; wash the beans in cold water; and trim stems, ends and any other bad spots. Leave the beans whole, or cut them into 2-inch pieces. If hot packing, boil the beans for five minutes, or if cold packing, leave them raw. Then fill the jars with the beans, and cover them with clean boiling water, leaving a 1-inch head space. If desired, add 1/2 teaspoon of canning salt.
Using a utensil, remove air bubbles from the jar sides, wipe rims clean, and put lids and rims on the jars. Place jars on a rack in the bottom of the pressure canner, in water, so that they are not touching each other or the canner sides. Cover, and bring the water to a boil, allowing steam to vent for 10 minutes before placing the weighted gauge. Allow pressure to build to the desired level according to the machine's altitude table. Once the canner reaches the required pressure, lower the temperature to maintain pressure, and process pint-sized jars for 20 minutes and quart-sized jars for 25 minutes.