Coming to Terms with Carotenoids

Carotenoids are one of the hottest trends in both the supplement and functional food industries, according to BCC Research's report, "The Global Market for Carotenoids," which found the global market for carotenoids was $766 million in 2007 and is expected to increase to $919 million by 2015.

Carotenoids, fat-soluble antioxidants, are most commonly found in bright yellow, orange and red fruits and vegetables, and, among other benefits, provide protection from free radical damage. In plants and algae, carotenoids serve two main functions, according to Gerald Cysewski, Ph.D., founder and chief science officer, Cyanotech, "protecting chlorophyll from photodamage and absorbing light energy for use in photosynthesis." Cysewski added animals cannot synthesize carotenoids on their own and must obtain them from dietary sources.

While there are more than 600 known carotenoids in nature, the most commonly found ones in the American diet include beta-carotene and alpha-carotene, found in orange-hued foods such as carrots, mangos, sweet potatoes and pumpkin; astaxanthin and lycopene, which can be found in both plants and veggies, like tomatoes and grapefruits, as well as in salmon and crustaceans; and the carotenoids derived from dark, leafy greens like spinach and kale, zeaxanthin and lutein.

However, there are also color-free carotenoids, according to Liki von Oppen-Bezalel, Ph.D., vice president of business development and marketing for IBR Ltd. "We discovered and manufacture natural carotenoids that are colorless, or more precisely, lacking visible color and having ultraviolet (UV) color." These carotenoids, phytoene and phytofluene, absorb only UV light and can be found in most carotenogenic organisms, including microorganisms, algae, fungi and some plants. The carotenoids help protect against excessive radiation and environmental stress.

According to Heather Richardson, associate product manager for Kemin Health, there are several methods for classifying carotenoids, but one of the most effective methods is to divide them into pro-vitamin A (non-oxygenated carotenes) and non-pro-vitamin A (oxygenated xanthophylls). "Pro-vitamin A carotenoids can be converted by the body into vitamin A; they include beta-carotene and alpha-carotene. Non-pro-vitamin A carotenoids are not converted to vitamin A, and include lycopene, lutein, zeaxanthin and astaxanthin."

Health Benefits

Nutritionally, carotenoids offer an array of antioxidant effects and provide protection from a host of different ailments, especially oxidative damage caused by free radicals generated by stress and external pollutants. Richardson explained: "Free radicals and reactive oxygen species are molecules that have been transformed to an unstable state by other reactions that can occur in the human body. Free radicals can damage lipids, proteins and sugars in our bodies, whether these molecules are present from foods or as portions of biologically important molecules such as DNA, RNA, enzymes, etc."

In the body, Richardson added, carotenoids have the capacity to "neutralize" the damaging potential of free radicals, reducing the potential damage that free radicals can induce both at a molecular and cellular level.

"Carotenoids are some of the best sources of antioxidants," confirmed David Parker, co-owner and cosmetic chef of The Body Deli. "Tens of thousands of free radicals are created in the body every second. When a free radical captures and electron from another molecule, a new free radical is created as the second molecule has a lone, unpaired electron. This new free radical seeks to capture another electron and become normal again. This continual process of forming free radicals becomes a chain reaction; unless neutralized, these free radicals can dam age DNA, fats and proteins."

When taken internally, carotenoids have been shown to help reduce certain cancers and heart disease, according to David Djerassi, president of Intrachem Technologies. A study review from the Cardiology Unit, San Camillo de Lellis Hospital, Italy acknowledged coronary artery disease (CAD) represents the primary cause of death in Western countries with an high incidence on human health.(Eur Rev Med Pharmacol Sci. 2008 May-Jun;12(3):183-90) Oxidative stress, induced by reactive oxygen species (ROS), also known as free radicals, plays an important role in the cause of this disease. Research has shown dietary phytochemical products such antioxidant vitamins (A,C and E) and bioactive food components (alpha- and beta-carotene) have shown an antioxidant effect in reducing both oxidative markers stress and LDL-oxidization process, supporting the beneficial roles of phytochemicals in the prevention of some chronic diseases.

Djerassi noted combinations of carotenoids are far more effective than single compounds. "In particular, high consumption of tomato-derived products has shown significant activity against prostate cancer, due to the presence of lycopene in combination with phytoene and phytofluene." Scientists from the University of Illinois carried out cell culture trials to evaluate the effects of tomato carotenoids and tomato polyphenols on growth of prostate cancer cells.(J Nutr. 2004 Dec;134(12 Suppl):3486S-3492S) They found not only from their experimental data, but also data from other laboratories, their results support the hypothesis that whole tomato and its phytochemical components reduce the risk of prostate cancer.

Djerassi added carotenoid mixes, as dietary supplements, are also effective photoprotectants against ultraviolet (UV) light-induced erythema, providing UV-protection year-round, when taken on a daily basis.

However, WH Leong, vice president of Carotech Inc., cautioned not all mixed carotenoid supplements are created equal. "The biggest disservice to the industry is the misrepresentation of carotene ingredients (carotene extracts) in the specification by suppliers/producers,” he said. “One example is sources such as algae beta-carotene and fermentative beta-carotene. These two products cannot be claimed to be a 'mixed carotene' when almost 98 percent of the carotene is made up of a single form of beta-carotene. It misleads the public into thinking that what they are taking is a true mixed carotene. They are not getting the protection of biologically the most potent form, i.e. antioxidant, inhibition of cancer, of carotenoids such as alpha-carotene and lycopene."

Carotenoids also have the ability to protect the skin when used in topical applications, said von Oppen-Bezalel.(Fragrance Journal. 2006; 34(3): 48-53) "The colorless carotenoids, being the most abundant in the skin, provide a long list of benefits to protect the skin and can potentially applied for anti-aging and photo-aging; antioxidants; anti-inflammatory; UV absorbers; sun protection by reducing UV damage; and a skin whitening agent that inhibits melanin synthesis."

Formulating with Carotenoids

For manufacturers, carotenoids can provide plenty of benefits to formulations beyond positively affecting health, according to Todd Sitkowski, senior marketing manager for DSM Nutritional Products Inc. "Carotenoids help maintain uniform color consistency throughout the shelf-life of [a] product line,” he said. “Unlike the tendency with food dyes and spice blends, which become unstable and fade over time, our carotenoid product forms are stable to heat, light and oxygen in all packaging types and storage conditions. The use of carotenoids in products provides a more 'consumer-friendly' label versus the use of certified food dyes."

However, formulating with carotenoids be difficult. "Because carotenoids are potent antioxidants, they are susceptible to oxidation and degradation if exposed to oxygen," Cysewski noted. Leong concurred, adding that ensuring the stability of carotenoids in a formulation is also a challenge.

To combat this, formulators must find an effective delivery system to ensure the integrity and potency of the carotenoids. Antoine Dauby, group marketing manager for Naturex, explained his company uses oil- and water-soluble extracts, as well as microencapsulated carotenoid ingredients. "Encapsulation has a number of advantages, including odor and taste masking, elimination of ingredient cross-interaction, increased heat stability and powders flowability," Dauby said. He added these benefits help reduce costs and machine down time, and noted encapsulation makes ingredients ideal for dietary supplements, cereals, dairy foods and nutritional bars.

For the colorless carotenoids, formulation is a bit easier. "There is no issue with formulating [phytoene and phytofluene] into any formulation that has a small portion that is oil-based, like most formulations in cosmetics," von Oppen-Bezalel said. She noted colorless carotenoids tend to be more stable in hot processes, a benefit when regarding formulation, and have an extended shelf life of upward to three years.

Indeed, oil immersion is a very popular delivery system, such as Carotech's oil suspension complex, utilizing vitamin-A-rich palm oil. Richardson remarked that corn oil, safflower oil or other vegetable-based oils are the most common.

Sitkowski explained powders are also a popular option for formulators. "DSM provides products in cold water-soluble powder and beadlets for coloration and fortification of water-based foods, instant products, beverages, puddings, confectionary and milk products."

While powders are convenient, Richardson cautioned formulators that special equipment is required to ensure that the carotenoids are homegenous throughout the product, adding dry powders are typically used in the formulation of tablet and two-piece hard shell capsules.

The Body Deli takes a different approach to formulation, Parker said. Because carotenoids are extremely susceptible to heat and oxidation, the company uses multiple plant and fruit sources in the manufacturing process. "This is why we adhere to a 'raw' food or living food approach to our formulating process. It is essential to process raw materials that contain carotenoid compounds with minimal heat and, if possible, refrigeration, to extend the potency and bio-availability of the beneficial phytochemicals." Subsequently, the raw approach means the products have a shorter shelf life. "Products generally lose their potency after 12 months. Many carotenoids degrade much more quickly, especially if they are in their most beneficial state." Parker that mild food-grade preservatives, such as potassium sorbate, are often used to combat oxidation and help the carotenoids maintain their effectiveness.

For products that have used powdered or oil-suspended carotenoid ingredients, shelf life generally ranges anywhere between 1 to 3 years. According to Richardson, carotenoids are light-sensitive and should be stored at room temperature in opaque bags or high-density polyethylene (HDPE) containers to protect them from excess light, moisture and heat.

While carotenoids require delicate care, the health benefits that they provide to consumers far surpass any inconveniences formulators might face.