Colorants are designed to mimic colors that a beer might otherwise have from a normal brewing process, but often without the associated flavors. By far the most important group of colorants used in brewing are the caramel colors and the related malt-based food coloring called Farbebier. People often “drink with their eyes,” so just as the colorant Mega Purple is used to give a darker, richer color to wine, so some brewers will seek to do the same to beer. Beer colorants can give beers the same colors as dark malts and the resulting colors can be measured and quantified by the same analytical methods as malt-derived color. They can also be used more sparingly to make minor adjustments to color, correcting inconsistencies in the brewing process or ingredients. Caramel coloring, which is widely used in many foods, is usually produced by heat treatment of glucose syrup, sometimes with food-grade chemical catalysts added to ease the caramelization process.
In most countries if a brewer desires to tint beer with colors outside the normal color range for beer, any coloring agent approved by the relevant authorities for the coloring of food products in general can be used. It should be noted that this is a highly uncommon practice in breweries at large, and in general such use of other colorants is only seen in connection with fruit beers, certain seasonal beers, and occasional oddities.
In Europe, the EU lists all additives to foods that can be marketed in the 27 EU member countries, and only caramel-based colors are approved for beer. This means that any coloring of beer with “non-beer” colors such as red, green, or blue will have to be achieved by addition of natural fruit or herb extracts. The U.S. Food and Drug Administration does not publish a “positive list” for colorants allowed in beer sold in the United States, but it requires any producer or importer to apply for the use of such in each case.
Bibliography
The Food and Drug Administration. Food. http://www.fda.gov/food (accessed February 17, 2011).