Fat content will cause a mess. You'll likely get a layer of fat congealed on the top. Kind of like when you put gravy in the fridge and you get that layer of fat on the top overnight.
Most grocery stores sell extract oils that a very concentrated and easy to use. Just adds a few drops. No need to go through all of the steps you would with zest. You can find them near the spices.
I've watched it from the beginning three times now. That's my new game plan everytime a new season comes out. I watch it right from the start just before the newest season starts. Such a good show!