[SPICLK2]

Tumeric is a chemical that has been extracted from plants!

Your scenario holds for any part of any food processing, not just food colours. The issue is that the definition of "natural" when applied to food is impossible to pin down. Can we process using solvents? What if those solvents were brewed? At what point does heat and pressure treatment become "unnatural"? Can I use an acid for processing? Can I use vinegar?

The various vegetable, seed and nut oils that form the basis for so many food products are very problematic if you want "natural" food.