High-Acid Foods Step 6  

Ladle prepared food into a hot jar leaving proper 'headspace'. This is the space at the top of the jar between the underside of the sealing disc and the top of the food or liquid. Over-filling and under-filling can result in seal failure. Head space is determined by the type of food:

¨      Jam, Jelly ¼ inch (0.5 cm)

¨      Fruit ½ inch (1 cm)

¨      Pickles, tomatoes ½ inch (1 cm)

-      Relish, Salsa, Chutney ½ inch (1 cm) 

Remove air bubbles by sliding a nonmetallic untensil such as a Bubble Remover or rubber spatula between jar and food. After removing air bubbles, readjust headspace if required.

Wipe jar rim removing any food residue.

Centre hot sealing disc on clean jar rim.

Apply screw band – screw band down until resistance is met, then increase to fingertip tight. Return filled jar to rack in canner. Overtightening prevents venting--air escaping--during heat processing and can cause seal failure. The "steam" created inside the jar during heat processing must be exhausted to allow the formation of a strong airtight seal.