from your post
>Nitrate is easily dissolved in water, which means that it is difficult to remove.<
When doing the veg broth, is the NPN in a form that does not go in the broth, or is there some that will nevertheless go in the broth?
Thanks
WIEL
Answer: If the Vegetables have NPN in them already it may pass into the broth?
This may be WHY it is so Important to learn to Select the Best foods to eat that do not contain NPN, and the refractometer may be the easiest way to do this?