If you boiled the mung beans, yes, they would turn brownish-green. and the water also light brown. It is good to use the water for anything at all. When I was just a vegetarian (now raw vegetarian) My wife would cook mung beans in pressure cooker and I would just eat them with cayenne pepper, Sea Salt and canola oil. My mouth waters by just mentining that.

You can also store the water in the ref. and use it to cook other vegetables.

Archus