This question comes from the Frugal Upstate Facebook page (go on by and join if you haven’t yet!). Most weekdays over there I post the “Lunchbox Report”–a picture and description of what I’ve packed in the kids lunch that day. Last week Kristen wrote:
I notice you pack leftovers or soup for your kids a lot. I have a question, what brand of thermos do you use? I bought one for my daughter’s lunches, and it doesn’t keep anything hot..does yours work well?
When I first started packing lunch for Princess 6 years ago (wow, has it really been 6 years since she started kindergarten!) I bought a wide mouth plastic thermos. Although I knew that a glass lined thermos (like the big old fashioned Stanley thermos I bought my husband for deer hunting) was the best for insulating, I figured glass and kids didn’t mix. And anyway-those things are pretty darn expensive.
So instead I bought a plastic wide mouth “lunch” thermos. It was terrible.
So after a while (and poor Princess eating lukewarm lunches) I went ahead and purchased a stainless steel wide mouth lunch thermos . At around $12 it was a bit more expensive than the plastic ones, but I’ve been using it for 5 years now and it’s still going strong.
Now if you really want to keep stuff warm in a thermos there are a few tips for you to use:
1. Preheat the thermos.
To preheat the thermos you fill it with boiling hot water, put the lid on, and let it sit for 3-5 minutes. You can boil the water in a kettle, microwave a measuring glass full of water & pour it in, or even in a pinch just use the hottest water from your tap. When your thermos is done preheating, pour the water out and them immediately place your food inside.
If you don’t preheat, as soon as you put your food in the thermos there will be a heat difference between the food and the interior wall–since heat will always move from higher temperatures to lower, the heat will move from your hot food into the colder wall of the thermos. So just by placing heated food inside it will actually get colder. When you have preheated the thermos then the interior walls should be much closer to the temperature of the foods. Of course this assumes #2. . .
2. Heat up your food.
When I heat food to pack in the kids lunch I try to get it as hot as possible-much hotter than I would normally serve their food to them. That way even with heat loss it still stays warm.
3. Pack it in an insulated bag.
Let’s make the poor thermos’s job as easy as possible here folks-pack it into an insulated lunchbox/bag to give it the best shot at staying hot.
4. Don’t use an ice pack.
Yeah, I know. . . it sounds like a “duh” thing. But there are some items that you just can’t send in a school lunchbox and have remain foodsafe without using an icepack-like yogurt for example. Although I guess you could put a hot thermos in there and then pack next to it an icepack and a yogurt, well, it just seems like you are defeating the purpose. When I pack a thermos I usually try not to include anything in the lunch that has to be chilled.
Now the kids swear that their lunches are still warm when they eat them, but I haven’t actually checked it out myself. I guess I should some time eh?
If you want more ideas about packing lunches here are a few of my other posts on the subject:
How to Save Money Packing Lunches ~ Carrot Sticks vs Baby Carrots ~ Four Reasons to Pack Your Lunch ~ Keeping Stuff Hot for Lunch ~ Lunchbox Planning for School ~ A Note on Portion Sizes ~ How to Make Lunch Sandwiches Fun