Coloring agents in food

Uses. Formerly used as a coloring agent in foods, drugs, and cosmetics... 

Source Reprinted with permission from R.L. Newsome, Natural and Synthetic Coloring Agents, in Food Additives, A.L. Branen, P.M. Davidson, and S. Salminen, eds., p. 344, 1990, by courtesy of Marcel Dekker, Inc. 

Newsome, R.L., Natural and synthetic coloring agents. In Food Additives, Branen, A.L., Davidson, P.M., and Sahninen, S., Eds. Marcel Dekker, New York, 1990. 

Copper compounds are used in agriculture to treat mildew and other plant diseases in the food industry as preservatives, additives, or coloring agents in preservatives of wood, leather, and fabrics in coin manufacture and in water treatment (ATSDR1990 Roncero et al. 1992). The use of copper-containing pesticides is traditional along the Mediterranean Coast, especially the use of Bordeaux mixture, a copper sulfate-based fungicide that has been widely used for more than a century to... 

The U.S. Food and Drug Administration (FDA) regulates the addition of nitrate and nitrite salts to fish products. Maximum permitted levels vary among products and types of fish, with up to 500 ppm residual sodium nitrate or 200 ppm sodium nitrite permitted as a preservative and color fixative in smoke cured sable fish, shad, or salmon (Code of Federal Regulations, 1981a,b Committee on Nittite and Alternative Curing Agents in Food, 1981). 

In the EC guidelines for coloring agents for foods [3.100], cosmetics [3.101], or pharmaceuticals [3.102], there are no references to mixed metal oxide pigments, and these are therefore not permitted. 

In order to prevent indiscriminate use, regulations have been developed by many countries limiting the types, uses, and amounts of food colors permitted in foods (142,151). Since different countries allow the use of specific food colors, it is possible that foodstuffs may be imported into a country that forbids the coloring agent present in the product. Therefore, methods capable of identifying and quantifying several colors simultaneously are desired in order to verify compliance to regulations. Information on the levels of these compounds in foods is also important to assess where the dietary intake levels stand compared to the ADIs (131,152,153). 

RL Newsome. Natural and synthetic coloring agents. In AL Branen, PM Davidson, S Salminen, eds. Food Additives. New York Marcel Dekker, 1989, pp 297-326. 

The carotenoid biosynthetic pathway leads to products such as vitamin A and its precursors carotene, responsible for the color of carrots or salmon, and lycopene, the color agent in tomatoes (Figure 11.12). Pathway products are sought for a variety of applications in food, medicine, and materials. Genes in the pathway from different organisms were combined and heterologously expressed in E. coli, a non-... 

Since the compound hydroxymethyl furfural is a major product of ketohexose dehydration, its presence can be used as an indication that caramel has been added as a coloring agent in a nonheated food system (66). In contrast, ketopentose dehydration produces furfural. Another dehydration product, bis-5,5 -formylfurfurly ether, can also be used to confirm the addition of caramel color (66). 

Other copper compounds are found in battery fluid fabric dye fire retardants food additives for farm animals fireworks (bright emerald color) manufacture of ceramics and enamels photographic film pigments (coloring agents) in paints, metal preservatives, and marine paints water purification and wood preservatives. 

In general, concerns over the safety of coloring agents in pharmaceuticals and foods are associated with reports of hypersensitivity " and hyperkinetic activity, especially among children. ... 

In 2002, the EU Scientific Gommittee on Cosmetics and Non-Food Products (SGGNFP) evaluated the safety of the compound lawsone as a coloring agent in hair dye... 

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