In the days before refrigerators, canning was the only means to ensure that food stays fresh. Reaching the peak of popularity during World War II, canning continues to be a popular means of preserving and storing homegrown fruits and vegetables. However, many people who use these storage devices are rightfully concerned about the reusability of the lids.
Canning lids are not reusable. Once the lid has been used, the sealing compound is indented and it becomes impossible to create another airtight seal. Therefore, you should dispose of canning lids once you’re done using them.
You will want to buy new lids, like these found on Amazon, for every round of canning that you do.
The rest of this article will cover some essential information regarding food storage using cans, including how canning lids work, how to tell if a lid has been used already, and how long you can keep canning lids. To learn more, read on.
How Can You Tell if a Canning Lid has Been Used?
Metal canning lids have a ring of reddish compound around the part of the lid that touches the glass jar. That compound should be smooth without any evidence of pressure lines or any other disruption to the integrity. If there are marks or indentations in the compound, the lid was either previously used or is no longer able to be used for canning. These lids should be thrown away because they will no longer be able to hold the seal required to keep the food fresh.
However, there are also a number of reusable canning lids on the market, so the answer given above does not apply if reusable lids are used.
How Do Reusable Canning Lids Work?
The most common name in reusable canning lids is Tattler. Invented in 1975 and first marketed a year later, Tattler lids have two parts to them as opposed to the single lid traditionally used.
A Tattler reusable lid comes with a red rubber ring and a plastic lid. The process is similar to that of metal lids, but there are a few small differences that can make a big impact on the success or failure of your canning.
- Before applying the lid, it is important to place both the rubber ring and lid in scalding water. This can be done easily in a Pyrex measuring cup or another vessel that is safe to hold very hot water. Leave the ring and lid in the water for at least one minute. They should remain there until you are ready to place them on top of the jar.
- After you have filled your sterilized, intact glass jar with whatever you are planning to preserve, remove the red rubber ring from the hot water, using a fork if the water is too hot in which to place your fingers.
- The red rubber ring should be placed on the top of the jar opening. The ring should be the exact diameter of the jar mouth, or you may have chosen the incorrect size of the lid for the jar being used.
- After the ring has been placed, remove the plastic jar lid from the water, again using a tool to remove it if the water is too hot. Place the lid on top of the ring so that no parts of the ring are protruding from under the edges of the lid.
- You then place a metal screw band (not included in the purchase of these lids) and turn it until it is what the company refers to as “finger tight.” Finger tight means you put the band on with one hand and do not hold the jar with the other. You twist the band until it is tight enough that the jar starts to spin with it on the counter. This may feel like it is not tight enough, but it is.
- Completely submerge the sealed jar in boiling water for ten minutes.
- After ten minutes, remove the jar and, using a dish towel or heat-resistant glove, IMMEDIATELY TIGHTEN THE METAL BAND COMPLETELY. If this step is not taken, the lid will fail. Traditional jar lids were not meant to be tightened when removed from the water, or the seal could be broken. This part of the process is often overlooked, leading to a disappointing canning experience.
- After the jar has cooled, remove the metal band and gently try to lift the jar by the lid. The lid should remain on, indicating a good seal, If the lid lifts at all, the contents will not be preserved, and spoiling will occur.
How Long Can I Keep Canning Lids?
If you choose to use traditional metal lids, it is important to remember that they have a shelf life. If you go over this shelf life, the food stored inside the can may not be fit for consumption.
Traditional metal lids need to be stored in a cool, dry place. Over time, especially if the lid is subjected to heat, the integrity of the compound ring will break down and will not seal properly onto the jar. When stored properly, metal canning lids will last up to 5 years.
However, that being said, it is always a good idea to visually inspect every lid before placing it on your jar. If any peeling is present, if there are any imperfections in the surface of the sealing compound or if the metal of the lid is bent or dented in any way, throw away the lid. As stated before, the metal lid should also not be reused if it has previously been used.
A general rule of thumb used to avoid wasting lids is to only buy as many as you will need in one year and write the date they were purchased on the box.
Reusable lids have an unlimited shelf life, used or unused. According to their own packaging, Tattler lids can be stored and used, “virtually forever,” although they do acknowledge that the red rubber ring may stretch over time. Therefore, you should still always inspect the ring to make sure it does not extend over the edge of the jar mouth.
If you are canning for your own household, the Tattler lids seem to be the way to go. A pack of 12 costs only a little bit more than a 12-pack of the metal lids. Just keep in mind, if you give your canned goods as gifts, you may not get your lid back.
I should also note that Tattler lids are a hot commodity, and the company sometimes has trouble keeping them in stock.
Unfortunately, traditional canning lids are not reusable if you need to maintain an airtight seal. As the seal gets indented after the first use, all subsequent uses will not be able to keep your food preserved for a long time.
There is another solution, though. Tattler’s reusable canning lids are designed specifically for multiple uses. If you frequently find yourself buying new canning lids to replaced used lids, investing in some Tattler lids would be an excellent investment.
If you do use traditional canning lids, you also need to be aware of their shelf life. With proper storage, the food you store in these lids should be good for up to five years. After this, the seal on the lid will likely deteriorate, so you need to be careful about eating any food canned using traditional lids that have been sitting for more than five years.