Generally, you should use young and tender beans for freezing because they tend to hold up better in the freezer. So, sort through your beans and remove the ones that look older, duller, or moldy.
Cut off or snap off both ends of the beans and remove the stringy fiber that comes with them. At this point, you can cut the beans into smaller pieces, about 1–2 inches long, to make them easier to store and easier to use.
Divide the beans into batches, and submerge them in a pot of boiling water for about 3 minutes. Some sources use a range of 2–4 minutes or until the beans are tender. . You can also add a bit of salt to the water to help soften them.
Spread the beans out evenly on a baking sheet (lining with parchment or wax paper optional) and freeze them for 60–120 minutes, or until firm. This process freezes each piece individually to keep them from clumping together when they’re frozen.
For added convenience, you can label your containers with the date of storage to keep track of how long they’ve been in the freezer. Finally, place them in your freezer, making sure that it’s at a temperature of 0°F.