Vacuum Insulated 16 oz/470ml Thermos Stainless King Food Jar Review

Last Sunday, I got up early to prepare a hot lunch for a winter picnic with my family out in the woods. It was chicken and noodle soup, the kind of hearty soup that warms you right down to your belly when the weather is frightful outside. And in November in England, the weather can feel cold indeed.

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My girls had “ordered” it the day before, browsing through their cookbooks and thinking hard about the type of soup they’d love to eat sitting on a log. When the soup was piping hot, I opened my cupboard and got out two brand new vacuum insulated 16 oz thermos stainless steel food jars. We’d never used them before. Trial-by-soup time! I wondered whether they would keep the soup hot/warm until lunchtime and how easy they would be to use for my girls.

Here’s my review of the Thermos 16 oz Stainless King Vacuum Insulated Food Jar w/Folding Spoon (buy it here: US link, UK link).

Design of the Thermos Stainless King Food Jar/Flask

The Thermos Stainless King series includes innovative products for everyday life. This food flask is one Thermos’ bestsellers and comes in several colors. We purchased ours in cranberry-red and immediately loved that it came with a handy metal folding spoon tucked in the screw-top lid and a bowl. For my girls, the folding spoon was definitely a top buying point and I can see why. It’s super convenient. They’d had other hot food jars in the past but the folding spoon was a great idea and made it quite special.

In addition, the food jar is a wide open-mouth type with a screw-top lid and the cup can be used as a serving bowl. That said, my girls like to eat directly from the food jar (because the food stays warmer inside) and use the bowl for a hot chocolate or spiced apple cider.

As far as size, the 16 oz/470ml model fits nicely in a day backpack and is a nice medium size that contains enough food for a hungry child or a moderately hungry adult, depending on what you fill it with.

How Green is the Thermos Stainless King Food Jar?

Thermos is a reputable company and everything that they design is top notch in terms of materials. As the name implies, the Thermos Stainless King Food Jar is mainly made out of stainless steel, a material that has a pretty hefty carbon footprint in terms of production and mining. However, because it’s made of stainless steel and stainless steel is virtually indestructible, this food jar will also last you a very long time and that’s a good thing if you enjoy the outdoors. Unless you lose the lid, you can practically call this Thermos food jar a family heirloom.

As a New York Times op chart on green bottles summarized, “If your stainless steel bottle takes the place of 50 plastic bottles, the climate is better off, and if it gets used 500 times, it beats plastic in all the environment-impact categories studied in a life cycle assessment.”

How to Fill the Thermos Stainless King Food Jar

At home, you’ll want to fill the Thermos food jar with boiling water during 10 minutes before filling it, as this will ensure that your food stays hot longer outside. If you’re using cold food, bypass this step and use ice cubes instead.

When you are ready in the kitchen, filling the jar with soup is super easy thanks to the wide mouth, a definite advantage over regular hot water bottles with smaller openings that always make a mess.  Use a soup ladle to avoid spilling and screw the lid really tight. Now it’s time to hit the trails.

Using the Thermos Food Jar Outside

When we first used this food jar in November in England, a heavy downpour drove us out of the forest and we had to take shelter under a building for our picnic. The temperatures were above freezing but with the wind, it felt cold enough to wear gloves, wool hat and scarves. After a nice walk outside, my 10-year old was starving and 8-year old was very eager to “try” her new lunch jar. Both jars were screwed so tightly that we helped our girls opening theirs while they unfolded their spoon. Once open, they dived in.

Food temperature verdict? The soup was hot. Actually, it was fuming hot and we could see steam coming out of the jar. So yes, the Thermos Stainless King Food Jar keeps food warm for at least 4 hours in winter conditions.

As far as user-friendliness, it’s a win too. My girls ate their soup, holding their food jar in one hand and the spoon in the other. Easy does it, no complications and no spills. The Thermos food jar is very child-friendly.

Packing the Thermos Food Jar On the Go

Last point worth noting. There were no leaks in the backpack. I speak from experience, not all hot food jars are created equal on this planet and this one is the best that we’ve tested so far. It’s also very compact and fits in day packs easily.

I don’t know if it would keep food warm overnight, as I’d like to fill the jar the night before and not have to get up at dawn to warm up a hot meal. If that worked, it would be pretty awesome. Alas, the Thermos website says something about that: keeps hot 7 hours, keeps cold 9 hours. Aw, forget it. No filling the jars the night before.

Thermos Stainless King Food Jar in Bullet Points

Here are a few more details on this great food jar:

• Thermos® double wall vacuum insulation for maximum temperature retention, hot or cold
• Unbreakable stainless steel interior and exterior
• Extra wide mouth is easy to fill, serve from and clean
• Cool to the touch with hot liquids, sweat-proof with cold
• Compact and insulated stainless steel serving bowl
• Full-size folding stainless steel spoon
• Capacity: 16 oz/470ml
• Dimensions: 3.7″ W x 3.7″ D x 5.6” H / 17.4 x 10.8 x 10.2 cm