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See why.Mason Jar Adapters
Mason jars make great food-storage containers, but the traditional lid offers limited functionality. We tested two products that promise to make mason jars more versatile.
Published May 1, 2015. Appears in America's Test Kitchen TV Season 17: Two Modern Stews
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See Everything We TestedWhat You Need To Know
From Brooklyn to Boise, Mason jars are being reused as everything from drinking cups to travel food-storage containers. But the traditional lid offers limited functionality.
We tested one product that promised to turn a jar into a to-go container: a 6-ounce plastic tub that drops inside a widemouthed jar but stays aloft thanks to a wide, flat rim. It turned jars 1 pint or larger into two-part containers, perfect for housing snack duos like hummus and carrot sticks or yogurt and granola, and was leak-free (we checked by dropping desiccant into the bottom of the jar, filling the insert with water, and shaking vigorously). We could fit generous portions of most snacks, save for large, crunchy items like tortilla chips.
A second product is a screw-on, flip-top plastic drinking lid, sold in both regular and widemouthed sizes. We found it comfortable to drink from and virtually drip-proof, even when we shook it upside down and tossed it into a commuter’s backpack. As a salad dressing shaker, it poured neatly and the jar’s grooves didn’t become slick with oil like they do when twisting on and off the traditional Mason jar lid.
Both products are top-shelf dishwasher-safe and resisted staining, even when we left them filled with iced black coffee or room-temperature tomato sauce for 8 hours. Neither can be used for hot items, as the glass jars aren’t insulated and will burn your hand, but we transport enough chilled or room-temperature foods and drinks to make these worth the small investment.
Everything We Tested
Highly Recommended
- Function: 3 stars out of 3.
- Ease of Use: 3 stars out of 3.
Inspired by the Japanese bento boxes for which it’s named, this 6-ounce plastic container transforms Mason jars into two-part food storage containers. The small tub fits neatly inside wide-mouthed Mason jars 1 pint or larger, but it stays at the neck of the jar thanks to a wide, flat rim, which creates plenty of space for snack duos like yogurt and granola, hummus and carrot sticks, or vinaigrette and salad. It formed an impressively tight seal, preventing leaks both inside and outside the jar even when we packed liquid ingredients. It’s top-rack dishwasher-safe.
Recommended
- Function: 3 stars out of 3.
- Ease of Use: 2.5 stars out of 3.
This twist-on plastic lid transforms a Mason jar into a drinking cup. A flip-top arm seals the drinking spout closed, forming a seal that stayed tight during transit. Once flipped open, the spout is wide and comfortable for drinking and the arm stayed back and out of the way. The lid can be sealed on so tight that we found it required near-superhuman strength to remove. It also worked as a salad dressing shaker, allowing us to mix up vinaigrette and pour it without dribbling over the jar’s grooves.
Reviews you can trust
Reviews you can trust
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