Pound cake should be yellow, pumpernickel bread deep brown and a cheddar cracker cheesy orange. Because most consumers taste with their eyes before a food ever goes in the mouth, bakers often formulate with colorful ingredients, or simply colors, because many times characterizing flavors need a little boost of color to get the mouth watering.
Colors are also used in bakery products and snack foods to help correct natural variations in the actual color of the product and compensate for changes that may occur during processing and storage. In some applications, colors add that “wow” factor that catches the consumer’s attention.
A key point to remember is that colors are added to foods for the sole purpose of coloring the product and, hence, are recognized by the Food and Drug Administration (FDA) as “color additives,” a term legally defined in Title 21, Part 70 of the Code of Federal Regulations (21 CFR 70). All color additives must be approved for use by FDA as a food additive. Color additives are not to be confused with colorants, which FDA defines in 21 CFR 178.3297 as coloring substances used in packaging that do not migrate to the food, drug or cosmetic inside.
FDA classifies color additives as either “certified” or “exempt from certification.” The former is also referred to as artificial or synthetic, and the latter, by default, is often characterized as natural. However, FDA does not define the term “natural” as it relates to color. In fact, it does not consider any color added to a food product to be natural. The exception is if the color is natural to the product itself such as coloring blueberry pie filling with blueberry juice. Thus, a yellow cake colored with turmeric, a color exempt from certification, should not be labeled “all-natural yellow cake.” What is acceptable to say is that it does not contain any synthetic colors.
In the US, seven color additives are certified for food use. Typically derived from coal or petroleum, they can be combined into an infinite rainbow of colors. All are identified with the prefix “FD&C,” indicating they are part of the FDA color certification protocol and approved for used in foods, drugs and cosmetics.
These seven are further classified as dyes and lakes. Dyes are water-soluble and oil-insoluble. They color a food matrix by dissolving in the system and are considered less stable than lakes because dyes can bleed.
When dyes are combined with mineral salts, they become insoluble and stabilized and are called lakes. The lakes color the food matrix through dispersion and work best in products that either contain fat or lack sufficient moisture to dissolve dyes.
Certified colors have come under attack because of research associating consumption with behavioral problems in children. In fact, in Europe, a law requires most dyed foods to bear a warning notice — a powerful incentive for bakers to avoid their use.
Working with exemptions
Exempt colors are isolated from plants, animals or minerals, and thus, they have more consumer appeal than certified colors. Because they are derived from so-called “natural” sources, formulators have less control over their function.
“Depending on the process, some exempt colors are challenging to use in baked goods and snack products,” said Faith Carlson, R&D technician, QualiTech Co., Chaska, MN. “Exempt colors are most successful in extruded pieces where the color is added right before extrusion and the heat step is quick compared with products that undergo lengthy proofing and baking steps.”
Because exempt colors vary so much, formulators should consult with suppliers about their use. “It is best to work with a food color scientist to understand the limits within a specific application,” said Rebekah Petges, technical support manager, baking and processed foods group, Sensient Colors LLC, St. Louis, MO.
She cited the example of pH limits for anthocyanins, red shades derived from black carrot and purple sweet potato. These are most stable at a pH below 3.8. At the higher pH levels common in baked foods and snacks, the shade shifts from red to purple. “In baking applications with higher water activity and high pH, anthocyanins will degrade,” she explained.
Source is important, too. “Vegetable-based anthocyanins, however, have greater heat stability than the fruit-based anthocyanins due to acylation properties,” said Jennifer Brown, global application scientist, DDW (formerly D.D. Williamson), Louisville, KY.
Heat plays a key role, according to Chad Ford, product manager, colors, WILD Flavors Inc., Erlanger, KY. He explained that if the anthocyanin beet color is used in a baked food, it has to be overdosed to compensate for color loss due to heating.
Often, color choice becomes a case-by-case decision, according to Jeannette O’Brien, vice-president and regional technical account manager, GNT USA, Inc., Tarrytown, NY. “While incorporating our fruit- and vegetable-based red and purple shades into grain-based bakery products can be challenging, many of these challenges are application specific,” she said. “Simply understanding all the production parameters can often mean the difference between success and failure.” For example, by working closely with a baker, the company successfully used a tomato-based colorant to deliver red to a muffin application.
“We have a fairly new acid-stable blue color that delivers previously unattainable vibrant colors from natural sources,” Mr. Ford said. “In the past, blue, green and some purple shades were virtually impossible to achieve with exempt colors.” WILD Flavors makes this color additive from fruit juice in a way that allows these colors to be achieved in both low and high pH environments. “Black and brown hues can even be obtained by combining the acid-stable blue with other exempt colors,” he added.
Heat stability must always be a consideration when choosing any color for a product formulation, according to Byron Madkins, senior director, product development and applications-colors, Chr. Hansen Inc., Milwaukee, WI. “Many of the carotenoids such as beta-carotene and paprika, while they do have good heat stability, can be even further stabilized by use of emulsification or encapsulation techniques,” he observed. These treatments protect the color throughout processing and shelf life and maintain the desired hue and strength.
In general, exempt colorants that provide yellow and brown are not sensitive to pH or heat, and the color is appealing and stable, according to Ms. Carlson. These include ingredients based on annatto, beta-carotene, carmine, paprika and turmeric.
There’s strength in combinations, Ms. Petges explained. “We typically achieve our customer’s color solution by starting with the natural building blocks that tend to be stable in a given application,” she said. “Then we will enhance these building blocks with other colors and incidental components to achieve color and stability requirements.”
The company takes those results and produces the color additive in an oil-soluble or water-dispersible form that works best under the customer’s manufacturing and packaging needs. “These custom natural colors are used in a wide range of baking applications to yield yellow to reddish orange shades,” Ms. Petges said.
Replacing certified colors
With close attention to detail, it is possible to make the switch from certified to exempt colors without the consumer noticing. “A current supermarket customer uses natural beta-carotene for its in-store cake mix instead of FD&C Yellow No. 5. It is very heat stable and gives a similar color,” Ms. Brown said. “A suggested starting usage level is 0.2 to 0.5% in the dry mix.”
Depending upon the application, “FD&C Yellow No. 5 can readily be replaced by turmeric or saffron in most baked foods applications,” said Jeff Greaves, president, Food Ingredient Solutions LLC, Teterboro, NJ. “FD&C Yellow No. 6 can be replaced with paprika and annatto. FD&C Red No. 40 can be replaced with a blend of reds such as beet or carmine and a yellow or orange such as annatto, turmeric, paprika, saffron or beta-carotene.
“Some of the newer exempt colors function well in topical applications and can replace synthetic lake colors in seasoning blends and to color tortillas and chips, sometimes even at a lower usage rate,” Mr. Greaves explained.
Important differences exist between exempt and certified color additives, with usage level differences being significant. Consider turmeric, which can provide a vibrant yellow shade to cereals and crackers. “Depending on the strength of the turmeric-based colorant, the usage rate can be several times greater than the use rate of its artificial counterpart, FD&C Yellow No. 5,” Mr. Ford said. “This is due to the fact that most exempt colors are not as concentrated as pure dyes. Further, because turmeric isn’t very light-stable, the packaging should protect the product from light.”
Not without controversy
Controversies exist within the category of exempt colors, particularly concerning carmine, also known as cochineal extract. This bright-red color is obtained from the carminic acid produced by some scale insects such as the cochineal and can be used, for example, to make cherry pie extra red.
Carmine provides an exempt alternative to Red No. 4, a certified color additive banned by FDA from food use in 1976, but carmine has produced anaphylactic shock in a few individuals. Also, cochineal extract is not considered halal, kosher or vegan. Whole Foods Market put carmine on its list of unacceptable ingredients. Considerable work is being done by color suppliers to find vegetable and fruit juice extracts that duplicate its crimson color.
Caramel colors contribute a range of shades to baked goods, from pale yellow to nearly black. They are used in dark breads such as pumpernickel and some ryes, in particular marble rye, where the caramel provides a consistent dark appearance to the whole loaf or the swirl. Chocolate-flavored products also often use caramel colors because they intensify the color impact without the cost associated with large amounts of premium cocoa.
“While the high color intensity of caramel color can extend cocoa powder, it has limits because of effects on texture and flavor,” Ms. Brown said. “Depending on the price of the cocoa powder, there is an opportunity for cost savings by reducing cocoa by 30% in your formula and extending it with maltodextrin and caramel color.”
Caramel colors have come under attack because of the four types of caramel coloring, two are produced with ammonia (Class III and Class IV) and two without (Class I and Class II). The types made with ammonia have been shown to cause various cancers in laboratory mice or rats. Current labeling regulations do not differentiate the classes of caramel.
But sometimes controversial ingredients are the best exempt colors for the job. “Red velvet is probably the most difficult color to replicate; however, carmine is a great alternative and when combined with caramel will give the rich red tone that consumers seek,” Ms. Brown said.