The three new varieties - named Dixiblue, Gupton and DeSoto - were specifically developed to withstand the hot and humid growing conditions in the southern states. They are the latest developments by scientists at USDA's Agricultural Research Service (ARS), which has worked on introducing blueberries to the region for over three decades. Blueberries, nature's only 'blue' food, are a rich source of polyphenols, potent antioxidants that include phenolics acids, tannins, flavonols and anthocyanins. The berries are said to have a number of positive health effects, including cholesterol reduction, and prevention against some cancers and neurodegenerative diseases such as Alzheimer's. The popularity of the berry has increased in recent years with the publication of more science supporting its health benefits, and an overall consumer move towards 'superfruits' and all things 'antioxidant'. According to ARS's Stephen Stringer, who breeds blueberries, the new DeSoto variety provides berries with an improved color, flavor and firmness, and can extend the Gulf Coast rabbiteye season by up to three weeks. Dixiblue has light blue berries and a slightly flat shape. Gupton produces high yields of light blue berries that are medium to large in size and claim an "excellent" flavor and storage quality. Another cultivar that Stringer is currently finalizing is said to be ideal for processing. This unnamed rabbiteye cultivar loads up with fruit, he said. "Being a smaller berry, it's not suitable for the fresh market, but it's ideal for use in processed-fruit goods, such as health bars, breakfast bars, and other fruit-inspired snacks." Besides breeding and storage tests, the ARS team, based in Poplarville, Mississippi, is also conducting research on the best time to harvest berries for optimal flavor and elevated levels of antioxidants, especially anthocyanins and phenolics. According to ARS, 30 years ago there were no blueberries growing in Mississippi. Now 2,500 acres are grown in the region, with the figure jumping to 30,000 acres when other southern states are taken into account, including Alabama, Florida, Georgia, Louisiana, North Carolina, South Carolina and Texas. This corresponds to $100m worth of fruits from the southern region alone. The berry, which is already firmly engrained in consumer minds for its apparent cholesterol lowering abilities, has become a popular ingredient in functional foods or products simply perceived as 'healthier'. Recent research on the berries include a study published last year that found that eating a diet rich in blueberries may reduce the severity of neurodegenerative diseases such as Alzheimer's or cognitive disorders relating to ageing. Another study from 2007 found that pterostilbene, a compound found in blueberries, may prevent the development of tumors in the colon. In 2006, scientists reported that blueberry extracts inhibited the growth of liver cancer cells in the lab, potentially adding to the growing list of health benefits for the 'superfood'. Another study that year found that blueberries could strengthen blood vessels against oxidative stress that may lead to heart disease.