Incorporate natural colorants into products.

Imagine eating purple bread, purple vinegar or blue noodles! Children in particular enjoy eating colorful food, and purple is extremely popular. So researchers at Food Science Australia are attempting to cater to that trend but also to parents' concerns that their children eat healthy, natural products.

The scientists are looking to incorporate natural food colorings into a range of different food products. As consumer demand for natural products grows, these natural colorants could replace synthetic food colorants. Red, purple and blue pigments--anthocyanins--give berries, flowers, fruits and vegetables their color. These pigments can be extracted and used as colorants in such foods as noodles, jam, beverages, yogurt and ice cream.

Perhaps the most interesting aspect of anthocyanins is their strong antioxidant abilities and their health-promoting properties. Scientists are currently investigating anthocyanins' abilities to lower cholesterol, prevent blood from clotting and defend cells against carcinogens. The natural pigments are safe to eat and have no side effects, we're told.

As you may know, anthocyanins are members of the polyphenolic group of compounds that have been dubbed "vitamins of the 21st century" due to their impressive medical and health benefits. Food Science Australia's researchers and collaborators in the Cooperative Research Center (CRC) for Bioproducts are focusing their research on the natural purple pigments of a type of Japanese sweet potato.

Rather than growing the whole plant in the field, scientists are growing clusters of sweet potato cells in fermentation tanks in the lab. The advantages of growing sweet potato under laboratory conditions are that the amount and quality of the pigments can be controlled. This method of growth also eliminates lengthy and seasonal growth periods, the need for large areas of land for crops, and high transport and labor costs.

Foods containing anthocyanins are available in Japan and are also being used in increasing volumes in Europe and the United States. Demand for these foods will grow as consumers learn more about the health-promoting properties of anthocyanins. For commercial mass production of sweet potato cell clusters, the challenge for scientists at Food Science Australia is to develop cost-effective ways to grow them and extract the valuable pigments. The researchers need to confirm productivity at a high volume of culture--commercially applicable, such as in a 10,000-L fermenter--before the technology can be useful to industry.

The CRC for Bioproducts is hosting the Third International Workshop on Anthocyanins 2004 (www.iwa2004.com) in Sydney, Australia, from Jan. 27 to Jan. 29, 2004. The workshop will review the latest scientific research on the health benefits associated with anthocyanin pigments.

Further information. Izabela Konczak-Islam, Food Science Australia, 11 Julius Ave., North Ryde, NSW 2113, Australia; phone: [phone]; fax: [phone]; email: [e-mail].