No, I’m not joking. I’ve done it many times.
You need a few things to do this. Go to your local welding supply house and tell him you want to rent a small bottle of nitrogen. He’ll want to know what you are using it for, so just tell him you want to pack some food.
You need to buy a regulator gauge, some hose, and some copper tubing.
I will take some pictures of the equipment and do a followup post in the next couple days. Stay tuned.