Colorants

Colorants are substances that confer artificial color to food. For example, mint is normally white, but all of us recognize mint as green. Colorants may also restore the original color lost during technological treatments to which the food product has been subjected. For example, candied fruit.

The organic and inorganic colorants can be extracted from natural products or chemically synthesized as the homologous structures existing in nature. Preparations obtained from foods and from other natural source materials by physical and / or chemical process, involving the selective extraction of the pigments, are considered dyes as well. Until the middle of the nineteenth century, dyes used for food were all of natural origin, derived from animals, plants, and minerals. This situation changed with the invention of the first synthetic dye in 1856 by Sir William Henry Perkin.

The market offers color additives in the form either of dyes or lakes.

Dyes are water soluble and are manufactured as powders, granules, liquids, or other special-purpose forms. They can be used in beverages, dry mixes, baked goods, confectionery, dairy products, pet foods, and a variety of other products.

Lakes are the water-insoluble form of dyes. Lakes are more stable than dyes and are ideal for coloring products containing fats and oils or items lacking sufficient moisture to dissolve dyes. Typical uses include coated tablets, cake and donut mixes, hard candies, and chewing gums.

We can distinguish the following:

  • Inorganic dyes can be synthetic or already present in nature, such as aluminum powder, and iron oxides and hydroxides (E172), titanium dioxide, silver, gold, and calcium carbonate. Iron oxides and hydroxides are banned in Germany for suspected toxicity at high dosages.
  • Natural organic dyes can be found in nature, whereas natural-like dyes are synthesized in the laboratory but with the structures identical to the structures already present in nature. They include Curcumin (E100), Riboflavins or Vitamin B2 (E101), Cochineal (E120), Chlorophylls and Chlorophyllins (E140), Plain caramel (E150a) (although it is not present in nature in this form), Caustic sulphite caramel (E150b), Sulphite ammonia caramel (E150d), Carotenes (E160a), Anthocyanins (E163), Beetroot Red-betanin (E163). Canthaxanthin (E161g), Carbon Black (E153) Vegetal coal is banned in the United States for its suspected carcinogenicity.
  • Organic synthetic dyes, obtained by synthesis and not found in nature, include tartra- zine, Quinoline Yellow (E104), Sunset Yellow (E110), Azorubine and Carmoisine (E122), Amaranth (E123) and Ponceau 4R (E124), Erythrosine (E127), Red 2G, Allura Red AC (E129), Patent Blue V (E131), Indigotine and Indigo carmine (E132), Brilliant Blue FCF (E133), Green S (E142), Brown FK and Brown HT (E155), Brilliant Black (E151)

The natural components must be provided in highly purified form in order to ensure the standardization of color. With the aim of increasing stability, natural colors can be formulated in suitable solid or liquids carrier materials.

Today synthetic dyes are widely used for coloring foods. Synthetic dyes have the advantage of being easier to manufacture, less expensive, and available in large quantity and they do not confer off-flavors to foods. They also have greater stability to light, pH variations, redox potential, and have the largest variety of hues that natural colors do not have.

In the United States, the FDA's permitted colors are subjected to rigorous safety standards prior to their approval and listing for their use in foods. They are classified as follows.

 
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