Food ยท Gear Review
Vacuum food jars. A cooker for one, within limits.
A good wide-mouth jar of about 24 ounces can keep a bowl of soup hot through a workday, and it can finish a pot of oats or rice that started at a full boil in a pan. Our top pick is the Zojirushi SW-KA75H, the one jar whose maker tells you how hot it stays, not just for how long. The Thermos Icon 24 oz is the value pick, and the Stanley Classic 24 oz is the one to throw in a truck.
Top pick
Zojirushi SW-KA75H
Holds
25 ounces, one large portion
Maker's test
163°F after 6 hours
At a glance: Zojirushi SW-KA75H
Strengths
- Zojirushi publishes a temperature, 163 degrees F after 6 hours, not just a number of hours.
- The lid is designed to relieve pressure as you open it.
- A 2-7/8-inch opening is wide enough to fill from a pan and clean by hand.
- Zojirushi warrants the vacuum insulation for five years in the U.S. and Canada.
Limitations
- It costs more than most 24-ounce jars.
- Zojirushi's figure is for water started at 203 degrees F, so thicker food may read lower.
- It is sold as a lunch jar, and Zojirushi does not describe it as a cooker.
By Dan Whelan, founder of New World Survival
Researched from USDA, FDA, and CPSC guidance, maker documentation, published testing, and owner reports. See our sources
The one thing to know
The smallest cooker cools the fastest.
Start with what the best-known jar maker says. Thermos's own guide to its food jars says raw or partially cooked food should never be packed in a food jar and relied on to finish cooking, and tells owners to heat food above 165°F before it goes in. (Thermos) We take that seriously. A jar holds one portion, and a small mass of food loses heat faster than a big pot: Practical Sailor found a 1-quart pot cooled about twice as fast as a 4-quart one. (Practical Sailor)
So we use a jar for a narrow job. USDA says to fill an insulated container with boiling water, let it stand a few minutes, empty it, add the hot food, and keep it closed, and that hot food should stay at 140°F or higher. (USDA) Bacteria grow fastest between 40 and 140°F, the danger zone, and food should not sit there more than 2 hours, or 1 hour above 90°F. (USDA FSIS) No USDA or FDA publication addresses finishing grains in a jar, and Thermos advises against relying on a jar to finish cooking, so what follows is our own line, drawn inside the USDA rules above. A preheated jar can finish grains that came to a full boil in a pan with their water: rolled or steel-cut oats, bulgur, couscous, and white rice. It can rehydrate a freeze-dried meal with boiling water, and keep a cooked soup or chili hot. Before you eat, a thermometer should read 140°F or above. Below that, if you cannot be sure it has been there less than two hours, throw it out.
Rice needs the most respect. The FDA says the vomiting form of Bacillus cereus illness most often affects rice and other starchy foods, and the toxin behind it survives 30 minutes at 121°C, so reheating a jar of rice that drifted cool may not make it safe. (FDA Bad Bug Book) Some things never go in a jar to cook at all. Raw meat, poultry, fish, and eggs are the clearest case of the raw food Thermos says a jar should not be relied on to finish. Dried beans, especially red kidney beans, need the FDA's soak of at least five hours and then a boil in fresh water for at least 30 minutes, which a jar cannot give them. (FDA) Soaking beans in a jar is fine; cooking them in one is not. Those belong in a pot. Our thermal cooker handbook covers the larger cookers that can handle them.
Recall: check any older Thermos jar
On April 30, 2026, the CPSC announced a recall of about 5.8 million Thermos Stainless King food jars, model SK3000 (16 ounces) and SK3020 (24 ounces) made before July 2023, and about 2.3 million Sportsman SK3010 bottles, sold from about March 2008 to July 2024. If perishable food sits in one for an extended time, the stopper can blow out when it is opened. Thermos had 27 reports of people struck, and three suffered permanent vision loss after being hit in the eye. The model number is printed on the bottom, and the recalled stopper has no pressure relief in its center. Stop using it. For the jars, throw away the stopper, send Thermos a photo, and get a free replacement stopper with pressure relief; every Sportsman SK3010 bottle is recalled and goes back to Thermos for a replacement bottle. (CPSC) Whatever jar you own, we empty it the same day, and we open it slowly with the lid tilted away from our face.
The field
Three jars, one portion each.
We looked at wide-mouth vacuum jars from 20 to 35 ounces, the range that holds one hearty meal. Ratings come from each maker, and price ranges from makers and retailers on November 8, 2026. We did not bench-test these jars. Notice that only one maker gives a temperature; the rest give hours, and "hot" is not a food safety standard.
Zojirushi SW-KA75H
- Holds: 25 ounces
- Maker's rating: 163°F after 6 hours
- Lid: relieves pressure as it opens
- Opening: 2-7/8 inches
- Weight: about 15 ounces
- Typical price: about $40 to $43
Thermos Icon 24 oz
- Holds: 24 ounces
- Maker's rating: hot up to 14 hours, no temperature
- Stopper: pressure relief
- Extras: spoon stored in the stopper
- Weight: about 1 pound
- Typical price: about $27 to $33
Stanley Classic 24 oz
- Holds: 24 ounces
- Maker's rating: hot 15 hours, no temperature
- Lid: insulated, doubles as a cup
- Warranty: lifetime
- Weight: about 1.4 pounds
- Typical price: about $25 to $39
Sources: Zojirushi rating, opening, weight, lid, and warranty from Zojirushi; its rating assumes water started at 203°F in a 68°F room. Thermos Icon details from Thermos. Stanley rating from Stanley; weight and warranty from the retailer NRS. Read November 8, 2026. Prices move often.
Our picks
We picked for heat, a wide mouth, and a safe lid.
For cooking, three things matter more than looks: how much heat the jar holds, an opening wide enough to pour into from a pan, and a lid that lets pressure out as you open it. After the 2026 Thermos recall, we gave the most weight to jars whose makers describe that pressure feature.
Top pick
Zojirushi SW-KA75H
A 25-ounce jar with what Zojirushi calls a Therma Chamber lid, and the only jar here whose maker publishes a temperature: 163°F after 6 hours, starting with water at 203°F in a 68°F room. That is well above the 140°F line, which is the number that matters, though a thick food like oatmeal will not behave exactly like water. Zojirushi says the lid is designed to relieve pressure from hot food as it is opened, the opening is 2-7/8 inches, and the vacuum insulation carries a five-year warranty in the U.S. and Canada. (Zojirushi) On November 8, 2026, the rose version was shipped and sold by Amazon.
Check price on AmazonValue pick
Thermos Icon 24 oz
A 24-ounce jar with what Thermos calls a Dura-Guard pressure relief stopper and a spoon that stores inside it. (Thermos) In a HiConsumption test published in 2024 that measured heat loss over 12 hours, it lost 24.1°F, the least of the seven jars tested; the other jars of 18 ounces or more lost 38.9 to 52.9°F. The test did not report starting temperatures, so read it as a comparison, not a safety rating. (HiConsumption) One caution on the hours: Thermos's product page rates it hot for 14 hours, while its own March 2026 food jar guide says up to 9. That gap is why we trust a thermometer over a box.
ThermosFor the truck or the trail
Stanley Classic 24 oz
Stanley's classic hammertone-green jar, rated by Stanley to stay hot for 15 hours, (Stanley) with an insulated lid that doubles as a cup and, according to the retailer NRS, a lifetime warranty. (NRS) At about 1.4 pounds it is the heaviest here, and owners prize it for taking knocks. Stanley does not describe a pressure-relief feature, so the opening habit matters most with this one: empty it the same day, and open it slowly, tilted away from your face. On November 8, 2026, the green 24-ounce jar was unavailable on Amazon, so we link to Stanley.
StanleyHow we link here
One link earns, two do not
The Zojirushi links go to Amazon, and New World Survival earns a small commission if you buy through them, at no cost to you. We did not find the Thermos Icon on Amazon when we checked, and the Stanley was unavailable there, so those links go to the makers and earn us nothing. Commission never decides a recommendation.
What owners actually say
They hold heat. The seals are what wear out.
These patterns come from Amazon reviews on Zojirushi's 25-ounce jars (about 2,500 ratings on the older SW-FCE75, averaging 4.5 of 5) and the Stanley 24-ounce jar (about 3,100 ratings, averaging 4.7), retailer reviews, and The Boat Galley, read November 8, 2026. We found too few independent owner reports on the Thermos Icon to describe a pattern.
The results
Owners of both brands most often praise soup, curry, and stew still hot at lunch, and Stanley owners like that the 24-ounce jar holds a whole can of soup. The author of The Boat Galley uses a small food jar almost every day for soaking dried beans, cooking rice, and making yogurt; soaking is not cooking, and beans still get their boil. (The Boat Galley)
The trouble spots
On the older 25-ounce Zojirushi, leak reports are mixed, and some owners report water getting inside the walls, which means the jar has lost its vacuum. Some find the older lid has more parts to wash than they would like. Stanley owners rarely complain, though one long-time owner reported a jar that stopped holding heat after about seven years.
The surprises
Owners who mention preheating say it makes the difference. Thermos agrees: skipping the preheat, filling partway, or opening the jar on the way can cut hot time by 30 to 50 percent, and an unheated jar may hold heat for only 2 to 3 hours. (Thermos)
How they fail, and what they cost over time
A lost vacuum, a tired gasket, and nothing else to buy.
The vacuum
Thermos says that if the outside of a jar feels warm while it holds hot food, the vacuum may be compromised. (Thermos) Water sloshing between the walls means the same. A jar like that is a warmer, not a cooker.
The stopper and seal
The gasket is what keeps the heat in and the soup out of your bag. Check it for cracks and a snug fit. On a Thermos Stainless King, also check the model number and whether the stopper has pressure relief in its center; the CPSC recall above explains why.
The habit
The recall injuries followed perishable food left in a closed jar for an extended time. (CPSC) Eat it the day you make it, and wash the jar that night.
The running costs
Almost nothing. A jar uses no fuel beyond the kettle of water to preheat it and the boil in the pan. The one tool that goes with it is a food thermometer, because it is the only way to know a portion is still at 140°F or above. Over the years you may replace a gasket or a stopper. The fuel savings are small because the portions are small; for real savings on family meals, our retained-heat cooking guide charts what a full pot in an insulated cooker saves.
What we didn't pick, and who should skip
Fine jars for lunch, and meals that need a pot.
Thermos Stainless King 24 oz
A long-running favorite, and the line in the April 2026 recall, which covers jars made before July 2023 with stoppers that have no pressure relief in the center. A new one with a center-relief stopper, from a reputable seller, is a reasonable choice; we picked the Icon because it led the only published heat test we found. If you already own a Stainless King, check the stopper before your next use.
Zojirushi SW-FCE75
The older 25-ounce Zojirushi, rated 154°F after 6 hours under the same test, (Zojirushi) with the most owner ratings of any jar here. Zojirushi does not describe its lid as relieving pressure, which is why the newer SW-KA75H is our pick.
Hydro Flask 20 oz
Well made, but in the HiConsumption test it lost the most heat of any jar of 18 ounces or more, 52.9°F over 12 hours. (HiConsumption) Fine for lunch; not our choice for cooking.
Low-cost 25 to 34 ounce jars
Amazon has many inexpensive large jars rated in hours. We found no published temperatures and almost no independent testing for them, and most listings do not say whether the lid relieves pressure. For a jar you will cook in, those are the two things we want to know.
Skip it if you cook for the family
A jar is one portion. For stew, beans, or rice for several people, a thermal cooker with its own pot holds far more heat. Our thermal cooker comparison covers those.
Skip it for beans and meat
Dried beans need a 30-minute boil, and raw meat needs to be cooked through, before any insulated container can help. A jar can keep them hot afterward, nothing more. Our food safety guide covers the temperatures.
Where it fits in your readiness
A daily habit that also works when the power is out.
A food jar belongs to the Sustain tier: small gear that keeps a person eating normally through a disruption. Most days it carries lunch. In a power outage, a winter storm, or an ice storm, one kettle of boiled water can make a hot breakfast and keep a cooked meal warm for hours, which stretches whatever fuel you have. If the water boils on a camp stove or grill, that happens outdoors: the CDC warns never to use gasoline, propane, or charcoal-burning devices inside a home, garage, or carport, or near doors, windows, or vents. (CDC)
Questions people ask
About thermos cooking.
Can you cook rice in a thermos?
Only with care. Bring the rice and water to a full boil in a pan, pour it into a jar preheated with boiling water, close it, and check that it reads 140°F or above before you eat it. The FDA ties the vomiting form of Bacillus cereus illness most often to rice and other starchy foods, and that toxin survives heat, so reheating a jar of rice that has drifted cool may not make it safe.
Can you cook oatmeal in a thermos overnight?
Many people do. Boil the oats and water in a pan, pour them into a preheated jar filled near the top, and close it. In the morning, check the temperature: 140°F or above, eat it. Below that, if you cannot be sure it has been there less than two hours, throw it out. A long overnight hold is when a jar is most likely to drift low.
How long does food stay hot in a thermos?
It depends on the jar, the food, and how full it is. Zojirushi rates its 25-ounce SW-KA75H at 163°F after 6 hours, starting with water at 203°F. Thermos says skipping the preheat, filling the jar partway, or opening it can cut hot time by 30 to 50 percent. Only a thermometer tells you whether your food is still at 140°F or above.
Is my Thermos food jar recalled?
Check the bottom. On April 30, 2026, the CPSC announced a recall of Thermos Stainless King food jars with model number SK3000 (16 ounces) or SK3020 (24 ounces) made before July 2023, and Sportsman SK3010 bottles. The recalled stoppers have no pressure relief in the center. Stop using it. Thermos replaces jar stoppers free with a pressure relief stopper, and replaces recalled bottles.
Can you put raw meat in a thermos to cook?
No. Raw meat, poultry, fish, and eggs never go into a food jar to cook. Thermos itself says raw or partially cooked food should never be packed in a food jar and relied on to finish cooking. Cook them fully in a pan, then use the jar only to keep them hot.