Natural color, otherwise known as colors exempt from certification, are food color derived from natural sources such as minerals, animals, and vegetables. They include paprika, turmeric, beta-carotene, grape skin extract, caramel, beet juice, saffron, carrot oil, and annatto extract among others. Certified colors, by contrast, are synthetic food color, otherwise known as lakes or dyes. Certified colors add a desirable flavor to foods while natural colors yield undesirable flavors to foods. The United States Food and Drug Administration has produced a list of the approved color permitted in the country. The list includes chemical class-Azo, chemical class-xanthene, chemical class-triphenylmethane, and chemical class-indigoid. The approved certified colors by FDA are nine in number derived from mixing several colors. The main certified color additives permitted in the United States are listed below. FD&C Blue No. 1 or Brilliant Blue FCF, FD&C Blue No. 2 or Indigotine, FD&C Green No. 3 or Fast Green FCF, FD&C Red No. 40 or Allura Red AC, FD&C Red No. 3 or Erythrosine, FD&C Yellow No. 5 or Tartrazine, and FD&C Yellow No. 6 or Sunset Yellow.

Dyes are food colors that dissolve in water produced in the form of liquids, granules, or powders. They are mainly used in jellies, confections, pastries, beverages, dairy products, dry mixes, and pet foods. Conversely, lakes are dyes that are insoluble in water. They are suitable for coloring foods rich in oil or fat, and those low in moisture such as candies, cakes, doughnuts, coated tablets, and chewing gums. The distinct difference between dyes and lakes in that lakes are more stable than dyes, and are insoluble in water while the dyes dissolve in water. “Blue 1” on the ingredient legend of a food indicates that the food contains either Blue #1 dye or lake.

The FDA considers various factors before approving a food color to evaluate its safety. The factors include the health effects of the color, both short-term and long-term; properties and composition of the food color; recommended amount for consumption, and several safety factors. FDA considers a built-in safety margin that determines the levels ideal for consumption without causing any negative effects.

A calorimeter is a light-sensitive device used to measure the amount of color absorbed by a medium. It measures color intensity based on the green, blue and red aspects of light that the object absorbs, similar to how the human eye works. Some light is absorbed when it passes through a substance or object while little of it is reflected. The function of the calorimeter is to determine the difference between the absorbed and reflected light in order to determine the concentration of a given color in the medium. A calorimeter applies the concept of Beer-Lambert’s law, which states that there is a direct correlation between the light absorbed by a medium and the concentration in the medium. A visible light spectrophotometer is also a light sensitive device that measures the concentration of color in a solution based on Beer-Lambert’s law. The calorimeter and the spectrophotometer function using the same concept of Beer-Lambert’s law. Both devices measure the difference between the absorbed and reflected light in the medium. However, unlike the calorimeter that measures the intensity of blue, green, and red colors, the spectrophotometer measures the wavelength of all visible colors.

FD&C Dye FD&C Lake Natural color/exempt color

Specific food product

Specific colorant

Why appropriate to use? Potential problem