Unlike regular twist-off lids that you find on products from the grocery store, flat-top mason jar lids are the type most commonly used for home canned food. When processed correctly, they provide a firm vacuum seal that ensures the food inside remains fresh for as long as possible.
Not everyone is familiar with canning jar lids, so getting them off can be challenging. Unlike twist-off lids, to a novice home canner, mason jar lids can seem glued to the top of bottles.
Fortunately, opening home canned food is a snap, and there are several ways to lift the lid on your delicious homemade food. There are two parts to the lids of home canned food: the metal band and the flat top.
How To Remove The Metal Band From A Canning Jar
Removing the metal band from a canning jar is similar to twisting off the lid of any regular bottle. If it doesn’t budge, you can try:
- Wear a rubber glove when twisting to get a better grip.
- Warm up the metal band by dunking it in hot water. The metal will expand, which may release it from the jar.
- You can try heating the metal band using a hairdryer if you prefer dry heat.
- Try prying it away from the jar by carefully inserting a flat utensil under the rim. Move the tool around the edge to unstick the band.
- If the band shows any sign of rust, add a lubricant like WD-40 to the thread. Let it penetrate before twisting the metal band to open.
How To Remove The Flat Lid From A Canning Jar
Once the metal band has been removed, the final hurdle when opening home canned food is the flat lid. Since it creates a vacuum seal to keep air out, the aim is to break the seal to release the cover.
Mason jars are valuable assets for any home canner as they can be reused indefinitely. The only time they are no longer useful is when they have a chipped or damaged rim since the jars will no longer seal. It is, therefore, essential to work carefully when opening home canned food to avoid damaging the jar’s rim.
There are three effective ways to lift the flat lids off mason jars:
- Use a churchkey can opener. Not everyone has one of these handy, old-fashioned tools, but if you do, it is the easiest method to open home canned food. Insert the lower hook under the lid and gently press down on the handle to break the lid’s seal.
- Locate the area where the jar’s glass threat is closest to the top. Then use a teaspoon to wedge against the top thread of the lid. Use a slight twisting action to break the seal.
- If all other methods fail and you still can’t open the jar, use a sharp object to carefully make a tiny hole in the center of the lid. The vacuum inside will immediately release, and the lid will come off quickly. Flat-top canning jar lids are single-use items, so making a hole in one is fine if you have to.
Why Are Jar Lids So Hard To Open?
When jars are properly sealed, the pressure inside the bottle is less than outside. This creates a secure vacuum seal that keeps the pliable metal section of the lid depressed.
Since the atmospheric pressure outside the jar is greater than inside, the lid is essentially continually being sucked inwards. To get home canned food open, it is necessary to gently break the seal by prying up one edge of the lid.