Click here for more info:)  http://www.physik.uni-augsburg.de/~ubws/nitrogen.html

Also, I found this great store in the UK that sells organic Cola Nuts!! Make your own Cola today!!!   http://www.herbsandtinctures.co.uk/cola-nuts-crushed-125g-p-178.html?zenid=a686dfcc461368bbbe1586f3a6108d9a