Journal of Food Science. 2013 April; 78(4): T642-7
This is the first national study on food additive use in India, collecting data on “sweets and savories.”
Their dye extraction and identification technique (using pure wool strands) is described, as is their method of measuring the quantity of each dye. They were able to separate, identify, and measure each of the permitted color dyes, as well as the non-permitted (illegal) ones.
Of the total of 2,409 samples analyzed, 16.4% contained non-permitted food dyes, and 58% contained permitted food dyes at excessively high levels.
The authors concluded that the allowable limits of color use should be reviewed and “governed by the technological necessity and the consumption profiles of the food commodities so that the vulnerable population should not unnecessary be exposed to excessive amounts of synthetic colors to pose health risks.”