Filling Formula: Don’t Pack Too Tight

Directions for filling canning jars are included in the canning recipes recommended by USDA and Clemson. Following these directions carefully is critical. The safety of a specific process has been determined for the specific food, the specific procedures for food preparation and the specific directions for filling jars provided in the recipe. Canning directions for whole kernel corn, lima beans, and green or English peas specify filling them loosely into canning jars and not shaking or pressing them down. Because they are so starchy, these vegetables absorb packing water and swell significantly during pressure canning; for the same reason, they require more headspace than other low acid foods. (The recommended headspace for raw-packed quarts of large limas is 1¼ inches; for raw-packed quarts of small lima beans, it is 1½ inches.)