Can You Put Ice Cream in a Thermos?

I scream, you scream, we all scream for ice cream! Who doesn’t love ice cream? Usually, we think of ice cream as one of those little luxuries, like bubble baths, that we can’t really take with us anywhere. But that’s not always true!

With the right thermos and the right preparation you can take ice cream with you on picnics, hikes and even camping.

Yes, you can put ice cream in a thermos. The vacuum insulation will keep the ice cream frozen for hours. Wrap in aluminum foil and a towel or place in a cooler with ice to keep the ice cream frozen even longer.

In fact, placing ice cream in a thermos or any vacuum insulate cup or container is the best way to stop it from melting, other than using dry ice or a freezer.

Taking ice cream with you on a hike or to a picnic is a sure way to make all the kids happy. Who doesn't love a scoop of ice cream on a hot day by the lake or river or at the beach?

Putting A Tub Of Ice Cream In a Thermos/Insulated Cup

If you purchase a pint of ice cream (the kind typically sold in a cardboard tub, such as Halo Top or Ben & Jerry’s) and a 30-ounce Yeti insulated mug or knockoff with similar dimensions then the tub can slip perfectly into the tumbler.

Put a couple of ice cubes in the bottom of the cup just to add an extra bit of cooling power.

Then slide in your ice cream tub into the insulated tumbler and put on the lid (if it'll fit on) and the ice cream should stay frozen for a couple of hours. Long enough to get you to wherever you are going.

You could even use dry ice if you want to be extra sure that your ice cream will still be icy cold at the end of the day. But you'll need to have access to dry ice and it's not easy to get in small quantities.

If you do choose to use dry ice, remember that it’s a good idea to wrap it with paper or insulate it.

Dry ice is so cold that it can make your ice cream completely frozen, and it doesn't thaw well. The outside can get mushy while the inside still stays rock hard.

Scooping Ice Cream Into Your Thermos

If you don't have a perfectly shaped ice cream tub then you can still put ice cream into your thermos.

This is how I usually pack my ice cream in my thermos when going camping or going for a picnic.

First, place regular ice in your thermos and close the lid. Leave for 10-30 minutes to completely cool down the metal on the inside of your thermos.

Then discard the ice and scoop your ice cream directly into your thermos.

Ideally you want to fill up your thermos completely so there is no air space in the thermos.

The more air space there is the fast the ice cream will melt.

How Long Will Ice Cream Last In a Thermos?

A thermos is a great way to keep ice cream frozen on the go but it won't keep the ice cream frozen forever. So exactly how long will ice cream last in a thermos before it melts?

In a thermos ice cream will last 4-6 hours before it significantly melts. It can last longer if you wrap the thermos in aluminum foil and a towel and ice cream can stay frozen up to 2 days if you put the thermos in a cooler filled with ice.

Usually if I'm just taking a pint or less of ice cream with me on a hike or picnic I'll try to eat it within 2-4 hours, especially if it's hot outside.

In colder weather I've noticed my ice cream can still be frozen 4-6 hours later, especially if I wrap it in foil and a towel and keep it in a cool place and out of direct sunlight.

How To Make Ice Cream Last Longer In Your Thermos

Packing your ice cream in a thermos will make it last a couple of hours before it starts melting.

But there are a few things you can do to make your ice cream last longer than this.

Start With Colder Ice Cream

Ice Cream In Freezer

A freezer is usually set to around 0ºF (-18ºC) however most household freezers do have settings that allow you to make it warmer or colder.

The day before you plan to pack you ice cream in your thermos turn down the temperature in your freezer to as cold as it will go. The colder the ice cream starts out the longer it will stay a good consistency.

Pre-Pack Your Ice Cream and Put Your Thermos In The Freezer

Another good way to make the ice cream last a little bit longer is to pre-pack the ice cream in your thermos and then put the thermos in the freezer the night before.

Leave the lid open so the cold can get into the thermos and turn your freezer down to its lowest setting.

Usually you should not put a thermos in the freezer, but this is when you put liquid in it which can freeze and expand. Ice cream won't expand if it's already frozen so in this case putting a thermos in the freezer is completely fine.

Pre-Chill Your Thermos

Before loading up your thermos with ice cream fill it up with ice and leave for 10-30 minutes.

The ice will cool down the metal on the inside of your thermos. Empty the ice then immediately scoop in your ice cream.

This won't make your ice cream last hours longer, but every little bit help.

Wrap Thermos in Aluminum Foil and a Towel

A thermos has a vacuum in it which stops heat transfer, but it isn't perfect and some heat will get through into your thermos melting your ice cream.

Any extra layers of insulation you can add will help the ice cream to stay frozen for longer.

I like to wrap my thermos is aluminum foil (learn why aluminum is a good insulator) as well as a towel and then keep it out of direct sunlight.

Place Thermos In a Cooler

One of the best ways to keep ice cream frozen for days at a time is to do all the steps above and then place your thermos inside a cooler filled with ice.

Place the thermos at the bottom of your cooler as this is the coldest spot in your cooler and only get it out when you're ready to eat it.

Doing this your ice cream should still be frozen after 1-2 days. After 2 days it's questionable as to whether or not it will still be frozen or completely melted.