The choice of colorant used in a product depends on an array of factors, from product formulation through shelflife storage conditions.


With an ever-expanding palate of colorant options for food and beverage applications, product developers have their hands full in trying to find the most suitable match for their needs. To stay ahead in an industry where consumers have so many options, companies must know how coloring can make or break a product’s success. Keeping in mind a few key considerations will help achieve optimal product processing, fortification and shelflife.

Because color attracts people to food and is said to stimulate appetite, the appeal of processed foods is tremendously increased through added colorants. From formulation all the way to consumption, the utmost care should be taken to ensure colorants are treated properly, especially since the wide variety of natural and synthetic colorants available may cause confusion with how to properly store these ingredients, before incorporating them into products. For example, improperly stored colors in powder form can cake or fail to disperse. If not under the required conditions, liquid colors can become sticky and fail to flow properly. Some processors opt to further mitigate this risk by dissolving or dispersing the colorant in a highly concentrated pre-blend, before adding to batches or an in-line process.

The combination of colorants a developer uses is often unique and dependent upon factors such as the food manufacturer’s packaging choice, product pH and the temperature experienced during its typical shelflife. It is, therefore, essential to observe the parameters listed on the handling and specifications sheets of the colorant to ensure optimal temperature, humidity and light protection. In the instance that handling instructions for a specific ingredient are lost or unavailable, it is best to keep ingredients in a cool, dark storage area until the correct parameters are determined.

Sourcing Colors

The source and quality of colorants purchased are essential to ensuring performance. Documentation of batch testing should be received with each shipment, and in-house testing for banned substances or other materials, such as herbicides, insecticides and metals, should be considered to ensure optimal safety and performance of added colorants.

As natural colorants become more popular--they are said to currently constitute more than 30% of the colorings market--this may be of higher concern, due to the range of non-food or exempt sources from which the colors may be derived. Chemicals or metals present may impact the shade of the end product, alter pH of the mixture or adversely affect other ingredients contained in the end product.

Effects of Manufacturing Processes

Product developers should also carefully consider how manufacturing methods may affect the colorant. Heat during processing can adversely alter added colors. Therefore, it is best to add colors nearest to the final step as allowable. For those applications where colorants must be added at the start of processing, a thorough assessment of the manufacturing steps should be conducted to determine if the processing temperatures can be minimized without detriment to other product components.

Microencapsulation, which creates a barrier between the colorant and the solution, may improve heat stability and decrease adverse effects on colorants. Ultimately, these options will decrease the chances of thermal oxidation, while maintaining nutrient value associated with the colorant.

Not All Colorants Act Alike

Not all colorants will perform similarly during manufacturing conditions, due to the various ingredients, as well as differences in physical and chemical nature. Dyes work by dissolving in aqueous solutions and are most commonly used in bakery products. Dyes are also optimal for beverages. Lakes, which work by dispersion, provide an opaque color and work extremely well in dry goods. Applications that contain fats or oils, or require light and heat stability, are best for lakes. Candies, cakes and dairy products are the most common uses.

Many colorants have legal limitations on the amounts that may be added to a specific application. For those that require adding the colorants during initial steps, an increase in dosage may be necessary to obtain desired coloring of the end products. For products using lakes, lower dosage levels are usually required--whether added during an initial or later step of the manufacturing process. In both cases, it is essential to be aware of any maximum allowances for a particular color being used.

Most blended colorings, which contain a mixture of two or more colorants, are more stable by comparison than other food colors and may not react to heat in the same manner as single coloring additives. These factors should be taken into consideration to utilize the lowest concentration of colorants with maximum product benefits.

Ingredients that provide stability in one product can be detrimental in another. For instance, vitamin C may provide enhanced color in one product, but cause fading in another. Products containing vitamin C also increase the risk of fading because of its propensity to scavenge oxygen. It is especially important these products are kept at the right light and temperature conditions to prevent oxidation.

What Else Might Affect Color?

Another facet is fortification beyond vitamin C. When considering possible interactions, the first question product developers should ask themselves is: are there other ingredients in the product that may affect colors such as vitamins, minerals or chemicals? If so, the most common changes due to fortification-coloring interactions may be taste-, texture- and aroma-related.

Microencapsulation can protect the fortified ingredients and minimize adverse effects on the colorants. This option also has become significantly more economical for companies to pursue, due to technological and distribution advancements. When fortifying with ingredients like iron, microencapsulation is especially helpful to maintain aroma and taste. It also allows increased heat stability and reduces cross-interaction between ingredients. Since natural colorants often are used at a higher dosage level than synthetic colors, they may be more disposed to unwanted interactions.

Products with elevated levels of carbon dioxide, such as carbonated beverages and those in modified atmospheric packaging, may also have an increased incidence of color fading. While the presence of certain gases is detrimental to color, they may benefit other aspects of the product formulation.

Packaging to Protect Shelflife

Product pH and exposure to light, oxygen and temperature after manufacture can all adversely affect shelflife. Ultraviolet (UV)-resistant wrapping or opaque packaging can overcome some colors’ tendency to fade quickly when exposed to UV. Dark-colored glass and plastic, for example, can preserve beverage shelflife.

Since protective packaging may be an issue in product marketing, compromises to consider include opaque packaging with the smallest front panel window possible; clear or translucent UV-resistant wraps; and minimal display in areas with direct exposure to UV lighting.

Thin films or coatings that contain alginates, starches, waxes, lipids or proteins can ensure color preservation. Lipid-based coatings may have an additional benefit of helping to increase the bioavailability of fat-soluble vitamins like A, D, E and K.

Modified atmospheric packaging is also a way to extend shelflife--by minimizing oxidation. This involves removing or replacing the atmosphere around a product before sealing. Oxygen also affects the product after the consumer opens it. If the packaging does not allow for proper resealing during home storage, the oxidative process begins after opening, promoting off-colors and browning.

Shelf-stable products also will be subjected to different conditions than those that are refrigerated or frozen. Refrigerated and frozen products can encounter higher temperature variance, due to frequent door openings and loadings, as well as high moisture conditions. This may lead to running or bleeding of colors, if not properly paired for the given conditions. Ice cream cakes and frozen novelties can be particularly susceptible to this condition. Though shelf-stable products may appear more versatile, the decreased water content, acidity and salt content of many may adversely affect the colorants in a product.

Consumers both consciously and unconsciously use colors to assess the quality of a product. Proper usage of colorants in products can add value by giving off a fresh and vibrant appearance. Additionally, they provide identity and can minimize color lost as a result of inadequate storage and adverse environmental conditions. In some cases, adding darker hues can even aid in protecting flavor and nutrients contained in food products. Particularly, some colorants may also help offset some brownish hues that are present with whole grains, but give products a spoiled or oxidized appearance. This technique has become more widely used for cookies and dessert products containing whole grains.

Though there are certainly other factors that can influence the success of a product, heeding the considerations associated with processing, fortification and shelflife will ultimately help companies color with confidence. pf

For more information, call 860-872-7000 or visit www.nerac.com.



Website Resources:

www.cfsan.fda.gov -- The FDA’s Center for Food Safety & Applied Nutrition
www.neelikon.com -- Website with a FAQ section on colorants, particularly dyes and lakes
www.gntusa.com -- Website with information on non-certified colorants

SIDEBAR

Colors can help to lure the consumer’s eye, but frequently, inclusions can catch the attention quite well, particularly in situations where the mix-in is highlighted on the retail package. However, these are not necessarily always indulgences. Take, for instance, almonds, which admittedly can be an indulgence but have healthy attributes, as well. Sterling Rice Group surveyed 388 American foodservice and CPG professionals and found 55% used nuts in their new product development during 2007. Almonds served as the “preferred nut ingredient” 31% of the time.

Of course, inclusions often purely exist to provide a treat, though a sometimes unexpected one. They have even made their way into fine dining, where innovative chefs have incorporated Pop Rocks and other candies onto menu items. For retail developers, adding inclusions can have drawbacks: as Steven Young, Ph.D., and Bruce Tharp, Ph.D., noted in the May 2005 issue of Dairy Foods magazine, particulate and variegated inclusions can “make or break any nutrient content target and, thus, any (‘good for health’) claim being sought.”

While not necessarily aiming for a health claim, Ben & Jerry’s has become well known for its unusual flavor titles, which often stem from interesting inclusions and amalgamations. Its U.S. limited-edition Goodbye Yellow Brickle Road ice cream includes peanut butter cookie dough, butter brickle and white chocolate chunks, while the company opted for pineapple chunks in its U.K. launch of Jamaican Me Crazy Sorbet, a chunky pineapple sorbet with Passionfruit swirls.

In Canada, Nestlé added an inclusion to an inclusion: brownie chunks complement its Loaded Max Cookie Dough frozen dessert under the Toll House brand. “Baked brownie chunks” are made with sugar, palm oil, eggs, wheat flour, cocoa, water, glucose-fructose, cornstarch, salt, flavor, modified soybean oil, soy lecithin, wheat starch and silicon dioxide. The titular cookie dough pieces comprise wheat flour, brown sugar, sugar, butter, chocolate chips (sugar, unsweetened chocolate, cocoa butter, soy lecithin), water, molasses, sodium bicarbonate, vanilla extract, soy lecithin, salt and cornstarch.

Meanwhile, Colombia has seen Company Meals de Colombia introduce Crem Helado Bubble Gum Flavoured Ice Cream. Included gummies are described in the ingredient legend as containing “sugar, glucose, gelatin, modified starch, acidulant (citric acid), artificial flavors, artificial colorants…[and] preservatives.”

In Austria, Mövenpick went for a fruit inclusion in Schätze Der Welt (Treasures of the World) Nougat Aux Prunes Ice Cream. The French-style, white nougat ice cream features Armagnac plums and white chocolate bits. The Austrian line debuted in June and includes a Chocolate with Chili flavor, though the line has been in Germany since January. There, varieties include Nougat aux Prunes, Almendras Estilo Andaluz with orange and cinnamon, Chocolate Picante (a “Mexican-inspired chocolate ice cream”) and Pistache à la Marrakech with figs and a hint of cardamom.
—William A. Roberts, Jr., Business Editor