Turmeric, a yellow root, imparts color and flavor to food and has been used as a color and/or spice for centuries. Turmeric is produced by grinding the rhizomes of the perennial herb, Curcuma longa. This plant is native to India, South America, China and the East Indies.
The colourings responsible for the bright yellow hue of turmeric are the pigments curcumin, demethoxycurcumin and bisdemethoxycurcumin.
Turmeric oleoresin results from the solvent extract of lipophilic compounds. Various extraction methods exist, yielding different yellow variations depending on the ratio of color compounds extracted. Turmeric and turmeric oleoresin are both stable to heat but are sensitive to light and alkaline conditions. Curcumin pigments are naturally insoluble in water; however, food color manufacturers circumvent this water insolubility by using particle size reduction and emulsifiers, which allow turmeric to be used in both aqueous and lipid products.
In the following episode of DDW’s Color in the Kitchen series, DDW Application Scientist Jennifer Brown shows us how to create naturally coloured Easter Eggs using turmeric and several other readily available natural color sources: