Blanching vegetables is defined as scalding vegetables in boiling water or steam for a short time. It is a critical step in freezing vegetables to protect flavor, color and texture.
Blanching also helps remove dirt, organisms, brightens up the color, and helps preserves some vitamins. It stops the natural enzymes in the vegetables from continuing to change flavor, color and texture. Underblanching can cause the enzymes to become more active and is worse than no blanching at all.
The blanching process is quick and each vegetable has its own blanching method and time.
Learn more about blanching and a list of blanching times for many vegetables from the National Center for Home Food Preservation.
