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Nerdy Science in the Kitchen

Best Vacuum Flask for Keeping Liquids Hot



Take your nice, warm drink with you anywhere you go with the right flask!
Take your nice, warm drink with you anywhere you go with the right flask! The Stanley Classic Vacuum Bottle from Amazon.

From cold beer to hot coffee, the ability to maintain liquid temperatures for longer and longer periods of time is a constant endeavor of industrial engineering. I recall my easily baffled grandmother waxing philosophic over the wonders of the Thermos: “It keeps the hot stuff hot, and the cold stuff cold. How does it know?!”

In a hurry? I like the Stanley Classic Vacuum Bottle at Amazon.

Well, turns out vacuum-flask technology is how it knows. Originally called the Dewar flask or bottle, this technology has existed in its bare form since 1892, when Sir James Dewar pioneered the technology amidst his studies in early cryogenics.

The Evolution and Popularity of the Thermos

Dewar was experimenting with the thermodynamic qualities of palladium when he stumbled upon vacuum flask technology. He formed one brass chamber within another, creating a narrow space of air between the initial flask and its outer shell.

He evacuated the air in this outer chamber before joining the two shells of brass at the top, thus creating a vacuum. This vacuum allowed the palladium to maintain a steadier temperature for a longer period of time (see some thermoses that keep drinks cold as well right here!).

Unfortunately for Dewar, he never patented the design, and two German engineers effectively snatched up the design in 1904, and patented the design as the Thermos. In much the same way as facial tissue paper is widely referred to by its leading brand name—Kleenex—as are mass produced vacuum flasks referred to as Thermoses, regardless of brand.

The iconic brand—and its many imitations—has thrived in the hot beverage economy domestically and internationally. The insulated vacuum flask design fits in as well at hardhat construction zones or single-track mountain bike trails as it does in congressional chambers. See how it stacks up against new, popular brands like the Yeti here.

The thermos is an iconic brand of vacuum sealed flasks - perfect for keeping liquids warm.
The thermos is an iconic brand of vacuum sealed flasks – perfect for keeping liquids warm.

Ecological and economical benefits of the thermos

As ecologic preservation and sustainability interests motivate more marketing and product development, the vacuum flask bottle has managed to stay ahead of the curve. Conveniently, the construction and usage of many of these bottles carries an implicit ecologic and economic value, without having required any substantial shifts in design.

Even before the physical constructions are considered, one can immediately point to the paper and plastic saving properties of the Thermos as a prime benefit—ecologically and economically—to its use. By using and reusing a vacuum flask bottle, one helps reduce paper and plastic cup and bottle waste, and saves money by bringing home-brewed coffee, tea, or hot chocolate on the go.

Now that we know that the vacuum flask bottle is here to stay—and for good reason—let’s take a look at some of the best models on today’s market.

Thermos Stainless King 40-ounce Beverage Bottle

Thermos Stainless King 40 Ounce Beverage Bottle, Midnight Blue

When exploring the available models of vacuum flask, it only makes sense to first check out the pioneering brand—the Thermos itself. The Thermos Stainless King 40-ounce Beverage Bottle is very much the industry standard in vacuum flask bottles.

Made with the patented Thermos vacuum insulation design, this bottle will keep hot drinks hot and cold drinks cold for up to 24 hours. The stainless steel interior and exterior prevents sweating of cold beverages and stays cool to the touch with hot ones. In customary Thermos fashion, the lid doubles as a sturdy cup. Find this thermos at Amazon.

Stanley Classic Vacuum Bottle

Stanley Classic Vacuum Bottle 1.1QT Hammertone Green

Perhaps the only other brand as associated with insulated food containers is Stanley. Proven time and again in the most extreme climates, their standard Classic Vacuum Bottle offers a slightly more streamlined and rugged take on the original Thermos design.

The naturally BPA-free 18/8 stainless steel construction prevents unsavory leaching of metal. The powerful vacuum insulation system keeps coffee hot or lemonade cold for up to 24 hours. A sturdy carrying handle facilitates easy carrying. The lifetime warranty protects your purchase for life! See it listed at Amazon.

Contigo West Loop Vacuum Insulated Stainless Steel Travel Mug

Contigo AUTOSEAL West Loop Stainless Steel Travel Mug, 16 oz, Bright Lavender

For coffee sippers looking to bring their java around in something a bit less bulky, the Contigo West Loop Vacuum Insulated Stainless Steel Travel Mug offers a sleek, urbane design. Lid-lock technology prevents the patented auto-seal button from accidentally deploying, guaranteeing against leaks on the go. The double-wall vacuum insulated stainless steel design keeps coffee or tea hot for up to 5 hours, and keeps cold stuff cold for up to 12. This fashionable design is available in a 16, 20, and 24-ounce capacity, and comes in 15 different stylish colors.

Want to check out the Contigo mug? Find it at Amazon.

Bring the warm with you

Vacuum flask technology is certainly not going anywhere. Unlike many rapidly changing designs, this technology works well and simply. Nothing fancy here – just intelligent, efficient, ecologically sound design that eases environmental impacts. There’s no reason not to own a vacuum flask bottle!

Additional Resources:

Image credit via Flickr Creative Commons: Kitty T. and Your Best Digs

Kitchen Professor author
About the Author: David McLemore

David learned to cook at an early age after his mother told him that he couldn't live on pizza forever, Dave uses his modest kitchen skills to recreate sorely-missed recipes from home and to occasionally make new favorite ones from places he is visiting.

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