Yeast transport (airplane)

Hey,

I worked in a brewery in Germany over winter break and the brewer gave me some of his yeast so i can use it at home. But what is the best way to transport it? The yeast is really active and is out of a fresh container he just got from the lab this week.
He gave me about half a gallon of it and i cant think of a way to transport in a small container or two that are able to hold the pressure and fit into my suitcase (it will be about 24hours from check in till i'm home and can release it, so it will build up a lot of pressure)
I'm open for every idea. Thanks

Freeze it and pack with dry ice. Box it up in and insulated container and check it with your luggage.

Just need a couple of small containers, maybe even plastic bottles, wrap in cling film for extra protection. You only need a small amount as you can grow it up easily when you get back.

You can put it in some socks for insulation if you want. I wouldn't worry too much though, I bet you'd struggle to kill the yeast even if you tried.