Yellow Turmeric:
Yellow Turmeric (the root of Curcuma longa) also called poor man’s saffron or Indian saffron, will give your dish a nice yellow color and an earthly, warm and peppery flavor. It is also used in Indian and Chinese medicine due to its anti-inflammatory properties. Recent studies have even shown curcumin (the yellow/orange pigment) to be as efficacious as some over the counter anti-inflammatories. The turmeric powder, that most of us are familiar with, is made by boiling the root and then drying and grinding the root into power. Turmeric is also used as a dye, and, as one becomes quickly aware when working with it, will stain your clothing, utensils and skin.
White Turmeric:
White Turmeric (the root of Curcuma zedoaria – therefore also just called Zedoaria) has a smell reminiscent of mango and taste similar to ginger, although with a stronger pungent taste. I purchased these in the local Indian store where they were named Amba Haldi. I’ve found them useful in curry dishes – since they do have a stronger taste. In terms of traditional uses, these roots are also used to aid digestion and have some anti-oxidant potential. For digestion, try making a tea infusion with a piece of root grated and boiled in water for a few minutes.