How to Select and Use a Thermos

It’s no secret that I like to send warm soup (or leftovers) to school with my girls in insulated Thermos food jars. I’ve actually made a habit of doing this on Wednesdays because I like to have one night per week when I don’t have to be “creative” with packing school lunches.

I make big batches of their favorite soups in advance, freeze them in individual jelly jars (leaving room at the top for the soup to expand), and then “voila!” lunch is pretty much done one day a week for weeks to come.

Tomato Soup for school lunches - in Thermos - by 100 Days of Real Food

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Not All Thermos Jars are Created Equal

So you can imagine my surprise when one Wednesday I had lunch with my daughters at school and asked to take a bite of each of their soups. Some readers have told me their insulated containers keep their kids’ food piping hot and others have said it’s so cold their kids won’t even eat it. So I decided to see for myself how warm the food actually was by lunchtime (about 5 hours after packing it in the morning).

Their lunch periods are only 20 minutes apart and the first daughter’s soup was fairly warm – even warm enough for a cold-natured person like me that prefers things pretty hot (soup, mochas, showers…you name it). Then I sat with my other daughter less than a half hour later and realized her soup was MUCH colder (she still ate it anyway – good girl LOL)!

But, from the outside their food jars looked identical…same brand, same Hello Kitty logo, etc. and after packing them at the same time using the same method/soup I just knew something was not right.

So I of course turned to my engineer husband who conducted a very scientific, controlled test to make sure the dramatic difference in temperature wasn’t just my imagination…and this is what he says about it:

Not all Thermos food jars are created equal! by 100 Days of Real Food

“First I inspected the food jars and even though they looked the same on the outside I found there was actually a difference on the inside. For one, the vacuum seal (beneath the bottom cover) on the colder jar looked inferior, and two, the shape of the bottom of the container looked like it would facilitate more heat transfer, which is not what you want when you’re trying to keep the heat in the container.

But to prove this theory I ran a simple test using one cup of boiling water (212 degrees) in each. Thermos brand food jars claim to keep food warm for five hours and after four hours the water in the ‘bad’ food jar (pictured on the left) was at 85 degrees, whereas the water in the ‘good’ jar (pictured on the right) was at 120 degrees…35 degrees is quite a difference!

I’m not sure if the vacuum seal was in fact broken or if this was just a knockoff/poor design, but regardless after calling the Thermos Company they sent me a new jar for free in exchange for me mailing them the ‘bad’ food jar at my own expense. Now we can be certain that both of our kids are consistently getting warm soup (or leftovers) at school!” – Jason Leake

Is “Pre-Heating” Food Jars with Boiling Water Worth It?

I’ve been told by dozens of readers that “heating up” Thermos jars with boiling water prior to adding the soup/food would keep it warmer longer. This theory does sound plausible so I started doing it myself hoping it would help!

But, being the skeptic my husband is, from day one he said he did not think the boiling water would make much of a difference for our application. He also didn’t like having to go through this extra step in the morning when he helped me get the girls off to school. :)

So once again my husband’s engineering background kicked in and he conducted another scientific test to determine if pre-heating the Thermoses made a difference or not:

“To test my hypothesis I got two identical food jars and labeled one as “pre-heated.” I filled that jar with boiling water, let it sit for 7 minutes, and then dumped out the hot water. I then immediately filled both jars (one pre-heated and one not) with exactly one cup of boiling water and closed the lids tightly.

After 4 hours I removed the tops and measured the water temperatures with our kitchen thermometer. The pre-heated one was only half a degree warmer…not even enough to notice!

So I’d say the pre-heating is not worth the extra time, at least for this scenario. That being said, insulated container manufacturers do recommend it for optimal performance, so perhaps it is worthwhile if you live in a very cold environment.” – Jason Leake

Our Advice

We think that good quality, insulated food jars and drink bottles can be incredibly useful when it comes to transporting and keeping your “real food” meals and beverages warm (or cold). In fact, at the pool one day I found myself drinking water out of my children’s Thermos bottles because their water was still icy cold while the water in my non-insulated steel bottle had turned lukewarm. I now have an “adult” Thermos bottle that I love and seriously take almost everywhere (in the car, on the plane, etc.).

So we highly recommend them, but when it comes to selecting a food jar, if possible, try to avoid the “bad” style shown on the left in the picture above. Also when it comes to adding food to the jars remember you can skip the pre-heating (i.e. boiling water) step. Simply warm up your food, add it to the food jar, put on the lid, and you should be good to go for about 5 hours.

There’s one other tip in regard to the lid though…I’ve found that I have to screw on the lid all the way and then slightly unscrew it (by maybe a quarter of a turn) to make it easier for my children to open it by themselves at school. After you loosen the lid, simply hold the jar sideways and make sure no food leaks out in order to test the seal.

Please share with us in the comments what your experience has been with using insulated food jars!

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174 thoughts on “How to Select and Use a Thermos”

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  1. Okay, I just noticed you have both the food jars and a regular thermos. I bought the thermos thinking I could put soup in it, is that not true? Would I need to buy a food jar as well?

  2. I found that I have to place boiling water in the thermos I have for at least 30 minutes to make any difference in keeping the food warmer longer anything under 30 doesn’t make any difference to temperature. That helps with keeping the food warm until my kindergartener lunch of 11 am and I put the food in about 7:15am. I use a thermos brand like the one tested in the post on the right only a different pattern of course! I sometimes will put boiling water in the thermos before I got to bed and it is still warm in the morning. Would love to see a test redo leaving boiling water for a longer period of time to see if you notice a difference.

    1. Hi Allie – Sorry for my late reply! Pre-heating will result in a slight improvement in performance, but my point is that for our purposes (kids’ snacks and lunches) the improvement is so small that it is not worth the additional 5-10 minutes it takes to pre-heat the thermos. I certainly don’t want to spend 30 minutes doing so…I am not a morning person!

      At some point I would like to test ALL of our insulated containers (we have some different styles and brands) with and without pre-heating to add some statistical significance. Not sure when that will happen though since we use them constantly. :)

  3. I bought the thermos you had a link to but realized it is a drink thermos (we can always use that!). I was actually looking for one for soup for the kids’ lunches. An 8 oz. seems so small- is that big enough for a main portion of soup for an 11 year old boy? Just wondering what size you use for soup.

    1. Katherine Walters

      I got a great “adult” size thermos at Target for my 10 year old son. It came with a lid that held a fold-up spoon. He loved it mostly for the manly-geekiness of the folding spoon (it IS a plain black thermos) but it holds 1 1/2 times more than the small kiddie thermos containers for food.

  4. Thanks for the information. We have two of these Thermos’ at home that I bought with the intention of sending hot food, but my husband has never trusted that they would stay hot. I think I will have to run the experiment at home so that he can see the results for himself. Sure would be great to be able to add soup to the lunch list! I freeze my soups in the jelly jars too (of course based on your recommendation), so this would certainly be convenient for a once a week option!

  5. Seems like some people on here just like to disagree with anything that is said.
    I love this page and it gives me a lot of helpful ideas. I dont always agree with everything and I even sometimes will say i dont agree but its in a way that is a conversation..not as a way of what seems like calling people out.
    If you have ACTUAL INFORMATION than i think that is great but to just br critical of the page seems pointless and well, annoying.

  6. Great post! I was surprised as well when I had lunch with my daughter the other day that her soup wasn’t very hot. As a Farmers Market Manager I am versed in food safety and was wondering about “keep ing hot foods hot” and her soup not being very hot by her late (12:30) lunchtime. I’ll take a second look at the thermos design now.

  7. I love this post! I’ve been sending heated leftovers in thermoses with my four kids to school for about 7 years now. I can’t tell you how many people have left horrified comments about food borne illnesses since I first started posting about this. BUT! if you put the food in while it’s boiling hot, and send it in an insulated lunch bag, it really is hot enough at lunch for them to enjoy.

    In addition to soup, I send reheated casseroles (like spinach enchiladas and chicken divan), bean dips, and homemade nacho cheese in our thermoses. And I haven’t had a single incident of food poisoning in 7 years, so I trust this method.

    I admit I’m still so skeptical of your test with heating the thermoses first. It looks like good science, but I don’t know if I can make myself put hot food into a cold thermos. I think I’ll at least run them under hot tap water before filling them, perhaps more for my peace of mind than for any scientific reason. Thanks for doing the research, Jason! So interesting.

    1. As a chef, I’ve done quite a few tests on how various food storage containers keep food hot and cold. It’s been 6 years since I packed lunches, but I still have my notes from making sure my kiddo wasn’t getting dangerous food since she had the late lunch and work schedules meant her lunch was getting made quite early in the morning. I took a weekend and did some tests to figure out the best course of action on planning and packing lunches.

      Putting in water that is boiling at 212 degrees, my thermos has it hovering around 145 at the 5 hour mark–so, not in the danger zone yet. Brothy soups can be added at about 200 degrees and have similar results (just entering the danger zone at 5 hours) but thicker soups can’t be heated that high without scorching to begin with, so they go in at about 160 degrees and enter the danger zone at the 4 hour mark–which means if being eaten by the 6 hour mark there is very little danger to even the most immuno-compromised persons like cancer patients, pregnant women and children.

      Now that being said, I put BOILING water in and let sit for about 10 minutes to heat the thermos up to get those results. Failing to do so meant that we lost a good HOUR and a HALF (sometimes two!) of time outside the danger zone–my boiling water was at 135 degrees at the 3.5 hour mark. Tomato soup at 200 degrees hit 140 degrees at about 3 hours and 45 minutes. Chili at 160 was 140 in a little over 2 hours. Boiling water in the thermos for 5 minutes gave us no noticeable change in time from not putting water in at all. Boiling water for 15 minutes gave us about an extra hour of time across the board, but we didn’t really need it so 10 minutes seemed to be the sweet spot.

      So certainly, specific containers may have different results than others, and the heat/density of the food when it goes in is going to have significant changes in the results too. As is how often you open the container to get those results. I took tests every hour until I got to the danger zone, then tested again using the same method but without opening until I hit that time–I found I lost about 10 degrees in 5 hours by opening each hour. But the results as listed here are for the second test, assuming it sat in the kid’s locker and wasn’t opened until lunchtime.

      1. I love this response. I felt like the test with hot water was missing something, but I couldn’t figure out why it would be different with soup vs. hot water. This makes total sense. Also, one of the websites for the food thermos’ specifically states to pre-heat the thermos with boiling water, so at least they think it is important too. Very interesting either way. :)

  8. My husband and I have recently discovered a brand that we have fallen in love with. Klean Kanteens have some vacuum insulated bottles that keep ice for 24 hours! and warm foods for 6 hours. (the ice I have witnessed, the warm foods I need to test out for the full 6 hours, I drink my tea in less than 6 hours) Anyway a ridiculous amount of time. They are stainless steel. A very environmentally conscious company. The Kanteens come in various sizes and in the spring they are introducing shorter food containers with wide mouths. And the best part is they have some holiday specials right now. Neither one of us work for the company, we just love their products. I mean really ice water after shopping in Texas heat, its amazing.

    1. It looks like some people have already mentioned Klean Kanteen! When reading the post my computer skipped to the end of the comments. :) Glad to see others like them too!

  9. I think your experiment also failed because after pre-boiling it you only filled it with a cup of water (assuming of course that the thermos holds over a cup of water… but I have never seen a thermos that only hold a cup). Thermoses do not work as well if they are not completely full, after drinking your first cup the remaining liquid begins to cool down quickly, because the thermal energy moves from the hot sources to the cold source. The more space that is left in the thermos, the faster it cools down, no amount of pre-boiling will help if it is not filled to the brim. If the tea/soup/whatever is boiling when you put it into your thermos it also makes a big difference. I am sorry if you took offense to my opinion, but keep in mind that you are advising people about things that are also just your opinion…

    1. Likes it hot! – You clearly didn’t read the entire post, nor did you clearly read Jason’s response. They were testing their kids’ Thermoses. If you haven’t ever purchased kids’ Thermoses, then you’re probably correct in saying that you’ve “never seen a thermos that only hold a cup.”

  10. I just had to comment on this post though because I saw so many flaws in it! I live in the Yukon, Canada, and it is a VERY cold place most of the year. I also work outside most of the year, and depend on my thermos for a warm-up!

    The first major difference in good vs bad thermoses is the brand: it has to be either Thermos or Stanley, although more expensive, they are the only ones that work. It is also critical to pre-boil thermoses,when you are in cold temperatures this makes the difference between piping hot and barely lukewarm tea.

    Moreover, trying your experiment once in only one brand of thermoses doesnt prove anything except that your husbands engineering background lacked statistics.

    1. Likes it hot! – Thanks for your comments. This was not a review of different brands of insulated containers, but rather information on our experiences with the Thermos brand containers we use. The mass of the stainless steel liner in the food jars is quite small relative to the mass of the hot food placed inside (water, in the case of the test), and therefore it’s thermal capacity is low. In other words, pre-heating the container is kind of like holding a match under a pot of water. It doesn’t make much difference. But you are correct that I did not test a statistically significant number of containers. Perhaps I’ll do some more tests. I did take statistics years ago by the way :)

      1. Jason…love your response. People can be soooo critical. Thank you to you and your Lisa for all your hard work in educating parents on how to feed their kids a healthier way (& in a way they will enjoy it)! Y’all rock!

    2. No! You did not “just have to comment”. Your opinion is as valid as the rest but please remember that it is just that, your opinion.

  11. Thanks a lot for the article and the tests. I have never heard of thermos containers to keep food warm before. I did not read the other comments, so excuse me if others have mentioned it before. But my gut feeling about keeping food warm for a long period of time (morning till lunch) is, that it is the perfect way to destroy vitamins as most of them are heat sensitive and the ideal breeding ground for micro-organisms.

  12. I use a thermos for my kids many times a week. For me it’s so much easier than preparing an inviting cold lunch. I print out their school’s hot lunch menu for the month, then try to plan to send similar lunches for my kids. In this way, my kids are eating the “same” things as their friends, but I know how it’s made. Plus, they tell me they like it better than the school’s food. I do pre-heat…and I have found that some of the larger bowl shaped containers vacuum seal and the kids can’t open them. So I use the same Thermos’ you are showing.

    1. Karen, that is BRILLIANT. It solves two problems at once: lunch planning (which I am not good at but now that you point it out, the school board has experts doing it for me) and the difference of home-packed lunches. I am going to use your tip! Thank-you!

      1. Sarahbee, ah you make me feel so warm and fuzzy! I asked my kids if the food is still warm when they eat it, and they both told me yes it’s still piping hot and we use thermos brand. I also put the lunch in a padded (cooler?) lunch bag, and if I also have cold items with a cold-pack frozen thing(I often use a frozen sponge for fear of a chem leak from those blue things)I separate the hot thermos from the cold things with a folded paper towel. Works like a charm

    2. Great idea, Karen! Over the past few years I’ve gotten rather lazy about packing lunches (can I blame it on the baby?) and my 11 year-old now insists that school lunches are better. I’m going to try your method and see if I can win her back. Thanks!

  13. I used to send my daughter with a character themed food jar but she complained that it wasn’t staying hot. This school year I opted for the adult version by Thermos and it stays HOT even after I pick her up from school. I paid about $18 at Target so really about the same price as the one that didnt work. So I use the old one for fruit

  14. http://amzn.com/B0017IFSIS

    This thermos keeps food steaming hot for hours. When tested without preheating, water that was boiling still measured 185F, 4 hours later.

    For packing hot and cold together:
    if you have a 2-compartment lunch bag, use that, with the ice pack placed so that it is not directly on top of the thermos in the other compartment.

    otherwise, wrap the thermos in a small towel to insulate it. This can be done even if you’re not packing an ice pack, to prevent heat loss.

  15. I was sending a piping hot thermos full of food to school with my child. She always said it was cold by lunch. THEN I found out that in her class, all kids were required to put their lunches in a fridge. She is special needs so didn’t realize the connection. The teachers though….. Really?

    1. I doubt the teacher is going to visually inspect each child’s lunch to determine appropriate storage. Perhaps as a parent, it would be wise to communicate a special need. Comments such as, “The teachers though….. Really?” are not going to help your child. :)

      1. Hi Diane;
        The Really? part of my answer was because my child is in a special needs class
        6 students. 3 aides and a teacher. They all require full time assistance..
        the instructors know what each child eats.
        They have to be helped to open their thermoses etc.

  16. i stopped sending hot food in my kids lunch a couple years for this very reason. How do you pack cold/hot food together? Does one cold and one hot thermos in the same lunchbox still do a good job? I’ll be lookiing for one of those flat bottom thermoses very soon! Thanks, great post as always!

    1. I usually put just one small ice pack under the cold container and try to make sure it’s not touching the thermos…seems to work for us. Good luck!

  17. I have heard that OrganicKidz is coming out with a thermal food container. I have been using their thermal baby bottles for a few years now and they are fantastic. Super cute designs as well. I can’t wait for the food container!

  18. Good post so i thought until i actually went to click on your link for the adult thermos which took me to amazon.com, $23 yep i could go for that price. However in the UK on the said amazon site the same Nissan adult thermos is £40 not such a good deal unless you were going to use it every day. How about the these

    http://www.amazon.co.uk/Aladdin-0-95-Litre-Bento-Lunchbox/dp/B002STGWBW/ref=sr_1_1?ie=UTF8&qid=1353958322&sr=8-1

    Sorry odd link but are they any better?

    1. Assistant to 100 Days (Jill)

      Hi Beverley. I’m not familiar with those particular ones. I would just check and make sure that they are BPA free. Sorry I can’t provide further feedback. Jill

  19. I love having a good reason to skip the pre-warm! Glad someone did a study on it. Thanks for this article–I would love to send more soup with my kid for his lunch.

  20. I love your blog!

    Can you share with me any other thermos type brands? My daughter is 10 yrs and doesn’t like “characters”. Something more plain…

    Thank u!!!

  21. I have the thermos on the left’s interior ( though the sportsman model) and have been more than pleased with it; I heat my soups to boiling and they still burn my tongue at lunchtime; I believe you when you say the other one is better, but just wanted to note that mine has not disappointed

  22. I think the test with the preheating and filling with boiling water may be misleading. If we were to fill our thermoses with boiling food, it would be true. But in reality the food that we are putting into a thermos is not likely 212 degrees. Preheating the thermos with boiling water, which is hotter than the food, may keep it warmer. A better test might be to preheat with boiling water, and then fill with water that is 160 degrees, and then test the difference. I might not be thinking right though, just a thought I had. :)

    1. Karen – The way people preheat the containers IS with boiling water, so that’s what I did (with one). For the test to be valid, I then needed to fill both containers with equal amounts of “food” at the same exact temperature, and then measure the “food” after time elapsed. The best way to do that was with equal volumes of liquid since it could be accurately measured (volume) and also stirred before measuring (temperature to ensure an average temperature reading (no gradients).

      It wouldn’t matter if it the liquid used after pre-heating was 212 degrees or 160 in terms of comparing the relative performance of the containers, however the widest possible temperature spread allows for more accurate results (lower percentage error), and also happens to emulate how WE use the food jars, which is with boiling hot oatmeal or soup, not 160 degree soup.

      1. I was just thinking that the preheating might make a difference in the case that the food was cooler, but if you are filling it with boiling hot food, that makes sense. I use my daughters thermos for leftovers, such as rice casseroles. Glad to know preheating is unnecessary! Thanks so much, love this site! :)

      2. I am wondering how many times you replicated the experiment. Were the “identical” thermoses switched and the experiment repeated?

  23. Hello!, love your website sooo much! Super helpful even for my family who is mainly vegetarian.
    On another note, Can you recommend a water bottle (adult size) that has glass on the inside but on outside is plastic? I have noticed that the typical water bottles made out of plastic(on the inside) make the water taste strange and don’t feel sanitary enough. thanks!!

  24. Thank you! I had purchased one a while back for my daughter even though she isn’t of an age to be packing lunches yet. I just went and checked ours – its a good one! Relief. My engineer of a husband would be very pleased with the scientific approach Jason took to this and I’m pleased to not have to add an extra step to food prep in the morning when she starts school full time.

  25. I tested food jars as well and found that the Thermos “King” food jar to be the best of the ones I sampled. After 4 hours, water that had been boiling when poured into the unheated thermos was still 185 degrees F.

  26. We enjoy the Klean Kanteen insulated bottles for keeping things hot as well. My bottle keeps coffee piping hot for hours. Their 12oz bottle would be a great tool for keeping soup hot. My kids are not quite school age yet so I have not tested the bottle, but based upon my hot coffee, I thing it is a fair assumption.

  27. I love Klean Kanteen’s insulated cups. They come in all sizes and keep liquids amazingly hot–or cold. I saw that they came out with a wide mouth, either 8 or 12 oz. one that I’m interested in trying–just for lunchtime soups, etc. Has anyone tried one?

  28. Why do you put the soup in individual jelly jars? Do you heat them up individually or via microwave? If you are heating and then distributing into a thermos, I would think the batch would be easier to deal with. But maybe I am missing something?

    1. You make up a large batch and divide it up into the individual sized servings of the jelly jars. the night before, you can take a frozen jar and put it in the fridge. In the morning you pop it in the microwave until boiling hot. Dump into Thermos. If you are going to give chili to two kids at the same time, you could divide up a large batch into 2 serving sizes as well.

      The time saver is that it takes only a few minutes to heat up a small jar for just one or two kids.

    2. I think it’s because they make a whole batch of soup at once (14+ servings from the picture) but are only sending soup once a week. This way they only reheat the amount of soup they are using since you should never refreeze something once it’s been thawed.

    3. Ronna – As Lori mentioned, we take them out the night before and place in the fridge to defrost. In the morning we empty the soup into a sauce pot to reheat on the stove before placing in the Thermos jar. The jelly jars are tapered so some soups will actually slide out straight from the freezer.

      1. Thanks for the replays. I understand about the bulk prepare and then distribute. It was the smaller jars I wanted clarification on. I have three boys and they would use larger servings. I would probably still freeze it in a jar large enough to accommodate all three of them and heat in bulk rather than the smaller jars. If for no other reason than to have one jar to clean up instead of three. I do however see the advantage of having the single servings if they want a snack or are fixing their own lunch for home. Thanks for a wonderful site.

      2. Be careful what kind of glass jars you use though. Make sure they are rated for the freezer, as those that are not can potentially leave micro-shards in your food.

  29. as far as preheating thermos jars, i’m still pretty sure it helps our food stay hotter. we live in alaska, and we keeo our heat at 58 during the day, and 52 at night. it’s 7 degrees outside right now, and when i get things out of the cabinets, they are COLD. enough to get condensation sometimes when they are warming up. if they are coming out of a fairly warm house, maybe it doesn’t make a difference. i would love to see that experiment done in a colder environment to see if I am wasting my time. I know that my coffee doesn’t cool as much in a heated mug in the morning. my tea is lukewarm if i don’t heat the pot and the cup first.

  30. Hi there! First off, I want to say I’m a huge fan of the site, I think its a great tool for people navigating the scary world of transitioning off “easy” food into real food. Also, as a first time expecting mother, I love seeing you feeding your kids good food, it gives me hope that it can be done, although my partner for some reason feels that kids will be “missing out” if we don’t let them have junk food :-/ Anyways, there’s just one thing about this post that concerns me…I’m a professional chef and seeing “5 hrs” and any temperature under 140F or over 40F definitely sounds an alarm. Of course by starting with quality ingredients and using proper kitchen safety your food gets a great head start, but no matter what, after 4 hrs in the “time, temperature danger zone” of 40F-140F its quite possible for unpleasant bacteria to multiply to unsafe levels. Prime targets are legumes, dairy, and meat/poultry. It can be as simple as stomach aches or general yuckiness but if you happen to ever get something that has a nasty bug in it, after sitting for 5 hours it will be fat and happy and ready to make you very very ill. Again, with the quality of ingredients you’re using its not likely you are going to run across ecoli or something…but for safest food practices, aim to keep those leftovers at over 140F for as long as possible, and keep the time they are between 40F and 140F to under 2 hrs.

    1. Elizabeth – Thanks for your comment…good to know. I would like to point out a few things:

      1) We share our advice from our experiences and research but encourage our readers to think for themselves and make their own decisions. The 5 hour time frame for keeping food warm is straight from the Thermos product description on their website.

      2) We pack the girls’ lunchboxes with ice packs, so the only food that is warm for any period of time is in the insulated food jars.

      3) The food in the food jars (soup or oatmeal) are both boiling hot (212 degrees) prior to placing them in the container. The water reached 125 degrees after 4 hours. Assuming a linear rate of temperature decline, the contents would not dip under 140 degrees until after 3 hours and 18 minutes, which means the contents would be under that temperature for 1 hour and 52 minutes prior to consumption in the worst case scenario (soup at lunch). The girls eat their oatmeal much earlier in the day.

  31. I don’t have experience with sending food in a thermos but I found the absolute best insulated travel mug. http://www.amazon.com/Contigo-AUTOSEAL-Stainless-Insulated-Tumbler/dp/B001RMGVU8 My husbands coffee is still warm when I pour the leftovers out at night 14 hours later! It’s great for cold drinks too. And it is seriously leakproof. I throw it in my purse and it has never spilled a drop. I have the non-insulated water bottle version that I use on a daily basis, too. Seriously, best drink container ever! :)

    1. Lauren I agree, the Contigo travel mugs are fabulous. We bought a set from Costco over a year ago and now have 6 plus the child size water bottles as well. My husband takes them to work and ice fishing and the contents will still be warm when I dump them at night.