By R. J. Foster, Contributing Editor
Colors serve myriad crucial roles throughout the food industry. They maintain consistent appearance despite variations in raw materials. Color is the first product characteristic judged by consumers, and is often considered an indication of quality, freshness, even identity. Most Cheddar cheese is orange, athough it comes from white milk. Colas are brown—or are they? And who would buy yellow mustard that wasn’t yellow? But for today’s health-conscious consumers, the right tone isn’t enough.
“There has never been a time when consumers have been more interested in providing their families with healthy and nutritious food choices,” notes Carol Locey, director of product management, colors, Kalsec, Inc., Kalamazoo, MI. For wellness-seeking shoppers, even the perception of “artificial colors” is a one-way ticket back to the shelf.
Perception is natu-reality
From a regulatory standpoint, there is no such thing as a “natural color.” FDA defines colorants as “certified” or “exempt from certification.” Certified colors like FD&C Red No. 40, Yellow No. 5, Blue No. 1, etc., are prepared synthetically and approved in batches by FDA. Exempt colors are derived from agricultural or biological sources. Despite government guidelines, consumers often consider certified colors as “artificial,” and exempt colors as “natural.”
Some exempt colors can be prepared synthetically. Nature-identical products, such as beta-carotene, canthaxathin, apocarotenal, some astaxathin and some lycopene, typically provide the same coloring effects as their “natural” equivalents. Still, people are happier thinking that the ingredients in their favorite foods came from nature—a tree, plant, fruit or seed—rather than a laboratory. This is why the general preference for labeling exempt colors is to call them by name: “beet juice concentrate (color),” or “annatto extract (color).”
Synthetic products are not without advantage. Certified colors are generally more able to withstand rigorous processing systems, high temperatures and extreme pHs that can have adverse effects on naturally derived colorants. Synthetic products also tend to be more economical and far less likely to affect finished-product flavor.
Many exempt colors are derived from healthy sources—colorful fruits and vegetables—the colorants for which are often the healthiest part of the product. Using these compounds to create or enhance the color of a product often provides unique opportunities to market potential nutraceutical benefits.
Deep purple, blue and red
Deeply colored fruits and vegetables owe their purple, blue and red hues to anthocyanins. These water-soluble compounds’ coloring effect and stability will shift with pH. In acidic conditions, around pH under 3.8, anthocyanins display rich-red tones. As pH increases, color and stability change, resulting in blue colors with reduced stability.
Grape juice and skins from wine production provide a plentiful, economical source for red-purple colors. Purple sweet-potato juice provides superior stability to light for beverage applications. Anthocyanins extracted from red cabbage and black carrots provide good heat stability, while black-carrot juice offers processors good stability across a greater pH range than most anthocyanins. “One of the most widely used anthocyanin reds is black carrot, which is an excellent choice to color beverages, confections, fruit preparations and dairy yogurts,” says Locey. Other sources of anthocyanins include elderberries, black currants, raspberries, strawberries, cranberries and blueberries.
