Weck jars are a popular canning in jar in Europe that are really catching on here in the States and Canada. They are unique in that they consist of a tempered glass jar, a rubber gasket, a separate glass lid and metal clamps to hold the gasket and lid in place. Where did these jars come from and how long have they been in production?
Our friends at Kaufmann Mercantile just published an interesting history of Weck canning jars on their blog. Turns out that although the name Weck is on the jar, the real Mr. Weck didn't invent the jars (he purchased the patent from its deceased inventor) nor was he around to grow the company into what it is today. In fact, Johann Carl Weck was only with the Weck company a few short years before he left to live in the French Alps at the turn of the 20th century.
Weck jars have been a popular canning jar in much of Europe but are somewhat new to American canners. They are gaining popularity, though, due to their good looks and the fact that they are BPA-free (the gasket is made of rubber.) Weck jars are not approved by the USDA for canning but from what I can gather, this is not because they are inherently faulty but due to the fact that the USDA has not tested them yet.
• Weck, a History from Kauffman Mercantile.
• The anatomy of a Weck jar and how they work from Food in Jars.
• For an interesting discussion on whether Weck jars are safe, view this thread.
Related: Pantry Style: Weck Canning Jars and a White Pen
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I fell in love with the shape(s) of these jars years ago, having purchased them from a local store. I use them for storage not for canning. Weck has canning supplies should one wish to use them for canning. The rubber ring keeps liquids from leaking, making transport of my salad dressings and soups for work possible. As for USDA testing.....I prefer the glass lid to traditional lids and rings. Hand wash the rubber seal and clips, pop the glass into the dishwasher! Stackable and wide mouthed, many utilize the same glass lid. I have used them to store homemade ice cream in the freezer. They make for a nice presentation...always receive positive comments about them.
I think Weck jars look fantastic but they are impractical once you open it. I have an opened strawberry jam in a Weck jar in my fridge right now, and I had to secure the glass top with saran wrap. I prefer a screw top lid any day.
@lamina: Good point about the Weck jar. I find that if I remove the rubber gasket, it allows the lid to nest into the top of the jar. This isn't a 100% foolproof seal, but it works for me. You can also you can purchase plastic lids from the Weck site for about 80 cents or less.
I agree they're beautiful to look at, but I wouldn't use them for canning, for the simple reason that you can't be sure if you've achieved a successful seal. I'd rather be safe with plain old Ball jars.
@Lamina: I just store my opened Weck jars without the rubber ring, but with the metal clips clipping the glass lid to the jar. Works great!
@Gardenstater: I don't understand why you are more certain of a successful seal with regular Ball jars? When you do a hot water bath with Weck jars, you know when it is sealed, absolutely. In fact, I check my Ball jars and Weck jars in basically the same way: remove the metal ring or the metal clips, and check that the lid and gasket are sealed to the jar. Also, the little tab of the rubber gasket will point down when the jar is sealed. As long as you are storing your Weck jars without the metal clips attached, you will know if the seal breaks, because the lid will no longer be stuck to the jar. I've canned tons of stuff with Weck jars and so far have only ever had one faulty seal. I love them!
I am by no means a master canner, but I have also had great success with the Weck jars. They make a plastic top just like Ball does.