Mines the USDA food database for recipes that satisfy a given daily nutrition target.
If you already know which foods you want to use for your soylent recipe but simply want to know the amounts to take of each, you can use this online diet problem solver.
In its current state, it may not be very practical, however it proves that a practical soylent recipe miner can be built.
See Documentation for all documentation or jump straight to the User guide for an introduction and usage instructions.