Interesting, is there any plans on opening up your calculator/analyzer to an API. I just launched http://imadefood.com a week ago, and there could be some mutual beneficial scenarios here. Let me know!
I don't think I can offer much of an API. As I mentioned in another comment, I gave up on trying to parse a free-text recipe. I avoid a lot of headache by directing users to enter ingredients from the database list only.
That being said, I'm open to talk about it - see my HN profile for email.
edit: @phugold - I like the idea of your site, but you might want to take note of the ability to immediately see recipies without having to register. It's great to be able to just dive right in rather than hitting a wall requiring login.