September 9, 2013
Public Outcry Forces Food Manufacturers To Seek Natural Coloring Agents
Brett Smith for redOrbit.com - Your Universe Online
Until a public outcry rose up against the practice, Starbucks had been using a food coloring derived from beetles to give its strawberry Frappucinos their rosy red color.
While insect-derived colorings are standard practice in the food industry, new research being presented at the 246th National Meeting & Exposition of the American Chemical Society (ACS) in Indianapolis suggests that alternative colorings from purple sweet potatoes or black carrots could serve the same function while providing additional antioxidant benefits.
According to study researcher Steve T. Talcott, a food scientist from Texas A&M, these natural food colorings, which had been used hundreds of years ago, are making a comeback in response to consumer demand, food manufacturers' needs and potential health benefits.
"The natural colors industry for foods and beverages is gaining in value as U.S. and international companies move towards sustainable and affordable crop alternatives to synthetic red colors and red colors derived from insects," Talcott said. "In addition to adding eye appeal to foods and beverages, natural colorings add natural plant-based antioxidant compounds that may have a beneficial effect on health."
Talcott noted one significant recent change, root crops like black carrots and purple sweet potatoes (PSP) are now being grown explicitly for the food coloring industry. These color-providing root vegetables are more frequently being considered as primary agricultural products, as opposed to grapes, the by-products of which are used as colors.
In the study, Talcott focused on the colors that can be obtained through PSPs, from light pink to deep purple. Available commercially in the United States since 2006, the unique potatoes can be used for french fries and taste like regular sweet potatoes.
The coloring agents in PSPs, known as anthocyanins, have proven to be stable food and beverage coloring that do not break down easily and have a relatively neutral taste. PSP anthocyanins also have other advantages over both synthetic red food colorings and insect-based pigments, including sustainability and ease of production. By comparison, the insects used to make food coloring feed on a particular cactus native to South America and it takes about 2,500 bugs to produce one ounce of pigment extract.
The PSP pigments are notoriously difficult to extract – although that may be changing. According to Talcott, a newly developed process is capable of extracting larger amounts of pigment from PSPs. As an added benefit, the byproducts of the process include starch and fiber, which could be used in a wide range of other processes. Alternatively, the byproducts could simply be composted for use in growing more PSPs.
The Texas food scientist said these new sustainable and economically viable processes could foster development of an American natural food coloring industry, with agriculture fields devoted exclusively to growing foods for use in coloring. Currently, the United States imports large amounts of the natural food coloring as PSPs are typically considered boutique crops.
At the symposium titled "The Chemistry of Functional Beverages," Talcott and others discussed beverages that prevent disease or promote good health instead of being simply for nutrition.