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Coffee Temperature Regulator

From Sweet American Classics

How we tested

Freshly brewed coffee can start out too hot to drink—and can too soon end up cold. Enter Coffee Joulies (“JOO-lees”), stainless steel capsules shaped like oversize coffee beans and filled with a proprietary material. The product promises to cool your coffee quickly to the ideal temperature (140 degrees) and keep it there.

We bought a set of Joulies for $49.95, which includes five Joulies and a carrying pouch, with instructions to use one “bean” for every 4 ounces of coffee. Then we brewed hot coffee and compared its temperature with and without Joulies in our favorite travel mug and in an ordinary ceramic coffee mug.

In the regular coffee mug, results were unremarkable (the temperature immediately dropped to a drinkable 140 degrees with the Joulies but then cooled as fast as the coffee without Joulies). In the travel mug, however, the Joulies made a big difference. The mug with the Joulies rapidly cooled to 140 degrees and held steady for 2 hours. The other mug gradually lost heat, starting out too hot and taking slightly more than 2 hours just to reach 140 degrees. Then both mugs slowly cooled at a constant rate.

So how do they work? The “phase change” material encapsulated within each Joulie has a melting temperature of 140 degrees. When it’s placed in an environment above its melting temperature, it absorbs heat, cooling the area around it until it is completely liquid. Then it slowly releases heat back into the environment until it becomes solid again. It works just like ice in a drink, which cools the drink to 32 degrees—the melting temperature of water—and then maintains this temperature until all of the ice is gone. Physics aside, the Joulies may work as advertised, but only if you’re sipping your brew out of a travel mug—and $49.95 is a lot to spend to address a small woe.

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The Results

Winner
Recommended

Design Trifecta 360 Knife Block

Admittedly expensive, this handsome block certainly seemed to live up to its billing as “the last knife block you ever have to buy.” The heaviest model in our testing, this block was ultrastable, and its durable bamboo exterior was a breeze to clean. Well-placed medium-strength magnets made it easy to attach all our knives, and a rotating base gave us quick access to them. One tiny quibble: The blade of our 12-inch slicing knife stuck out a little.

$248.64*
Recommended

Schmidt Brothers Downtown Block

This roomy block completely sheathed our entire winning knife set using just one of its two sides—and quite securely, thanks to long, medium-strength magnet bars. Heavy, with a grippy base, this block was very stable. An acrylic guard made this model extra-safe but also made it a little trickier to insert knives and to clean; the wood block itself showed some minor cosmetic scratching during use.

$141.90*

Schmidt Brothers Midtown Block

This smaller version of the Downtown Block secured all our knives nicely, though the blade of the slicing knife stuck out a bit. With a base lined with grippy material, this block was very stable. An acrylic guard afforded extra protection against contact with blades but made it a little harder to insert knives and to clean; the wood itself got a little scratched during use.

$67.99*
Recommended with Reservations

Swissmar Bamboo Magnetic Knife Block

This small, scratch-resistant model had a stable, rubber-lined base and could hold all our knives, though the blade of the 12-inch slicing knife stuck out a bit. But inch-long gaps between its small magnets made coverage uneven and forced us to find the magnetic hot spots in order to secure the knives. Its acrylic guard made it safer to use but harder to insert knives and to clean.

$49.93*
Not Recommended

Messermeister Walnut Magnet Block

This handsome block was done in by its shape—a tippy, top-heavy quarter-circle that wasn’t tall or broad enough to keep the blades of three knives from poking out. It lacked a nonslip base, and its extra-strong magnets made it unnerving to attach or remove our heavy cleaver. Finally, it got a bit scratched after extensive use.

$129.95*

Epicurean Standing Knife Rack 12"

This magnetic block sheathed all our knives completely, though with a bit of crowding. But it was hard to insert each knife without hitting the block’s decorative slats on way down, and because the block was light and narrow, it wobbled when bumped. Worse, we couldn’t take it apart, so splatters that hit the interior were there to stay. Additionally, the outside stained easily, and when we wiped it down, the unit smelled like wet dog.

$99.95*

Kapoosh Rondelle Knife Block

This model stabilized knives with a mass of stiff, spaghetti-like bristles that shed and nicked easily after extensive use, covering our knives with plastic debris. While all our knives fit securely, several of the blades stuck out, making this unit feel less safe overall. Finally, though the bristles could be removed and cleaned in the dishwasher, their nooks and crannies made this block hard to wash by hand.

$24.99*

Kuhn Rikon Vision Knife Block, Clear

This plastic block required us to aim each knife into the folds of an accordion-pleated insert that was removable for easy cleaning but got nicked easily with repeated use. Because we could only insert the knives vertically, longer knife blades stuck out; a cleaver was too wide to fit. The lightest model in our lineup, this block was dangerously top-heavy when loaded with knives.

$35.88*