I am helping out with a new plant to crush organic and non-GM soyabeans. When we change product from non-GM to organic, we need to clean and flush the system. I need to verify the flush procedure. I know that there are metal microtracers available but I'm not keen to put them through an extruder and oil press. I think coloured food dyes could be a simple an cheap method. Do you know of any commercial products, which will come with a quantitative method of testing residues from one batch in the floowing batch?
I hope you can help.