You can buy special made pliers which can be used to squeeze the juice out of leaves etc !
I made my own using a vise-grip pliers and welded a piece of stainless steel pipe cut in 1/2 to each head of the vise-grip so that one would mash down in the inside of the the pipe 1/2 !
You can buy some made like this from pike agri-labs, I believe ?
And you may be Correct in seeing that "ALL" foods with Low Brix readings and sharp Lines may have NPN in them !
Now maybe "YOU" are beginning to see "WHY" so many people are Sick and Diseased from the Poor Quality foods which they are eating ?