Lunch Meal Time On-the-go

Best Heat Retention Across Kid’s Thermos Containers

August 9, 2022
3 Thermal Jars

With September around the corner, I’ve been looking around into lunch options for J and looking at the different jars and bentos on the market. Today I’m testing out a few thermos containers we have at home, starting off with the 3 that I purchased for kindergarten.

As I come across more, I’ll update this blog post.

To start we have:

  1. Thermos 10oz Food Jar
  2. Reduce 10oz Kids Food Jar
  3. SkipHop Zoo Insulated Food Jar

High Level Overview of Thermos

CapacityHOTCOLDDishwasher Safe?Stainless SteelPrice
Skip Hop11oz7h5hNoUnknown~20

The Testing Method

This is not meant to be very scientific or technical here. What I’m looking for is to see how consistent the heat retention is across the 3 jars I have and if there are any with a significant difference.

I used the Braun No Touch Infrared Thermometer for the purpose of this test since it’s able to test food and water as well. Across the 3 jars they all started with 55’c (131’f) and I plan to test again within 4 hours – which would be the standard amount of time from the time you packed the lunch to when they would eat at school. Based on the the claims of all 3 jars, I’m expecting that the numbers should be pretty consistent – maybe with Skip Hop performing better because of the extra ounce of water + extra 2 hour of heat claim.

Test Overview:

  • Heat water to 160’f
  • Pour each into each jar half way, then go back fill all the way – leaving room for lid
  • Scan with Thermometer
  • Test within 4 hours

Observations & Results

At the 1 hour mark, I touched the exterior of all 3 jars. The Thermos and Reduce jar were completely cool to the touch, meanwhile the Skip Hop had a very slight warmth to it.

Starting TempFinal Temp
Skip Hop55’c32’c
Temperature reading after 4 hours – All thermal jars filled with water boiled on 160’f setting

After the 4 hour mark, I opened each jar one by one to test the temperature. Across the board they are not as hot as they were when initially filled. Thermos and Reduce had similar results, scanning at 43-44’c and felt nice and warm when I poked my finger in. If it were a soup, I think it would still be warm for a child and might even benefit from blowing on it prior to chowing down. The Skip Hop one was more than a 10’c difference at 32’c – when I touched it, it felt like room temperature! Which is actually pretty concerning, so I won’t be using this jar for any hot foods or my child. I may try to test again with ice water across the 3.

Final notes

I’m actually surprised and disappointed that the Skip Hop container which claimed to keep foods hot 2 hours than the other two was actually the least warm – room temperature even. I think my conclusion is to test out filling your thermal containers at home with food you plan on packing and see how they hold up personally – I think that’s the only way you feel more confident that foods are being kept at safe temperatures.

Keeping food warm/cold longer

When packing food for your kids, I believe to see best results, they recommend that we fill our thermos with boiling hot water first and let it sit for about 5-10 minutes, pour it out then fill it out as fully as possible to keep the heat. Also recommended that the food going in, is as hot as it could be… like boiling soup all the way first.

As for cold, you can pop it in the fridge or freezer as you prep in the morning – or fill it up with ice water and seal it back with the lid.

You Might Also Like

No Comments

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.