Blackberries are a 90's-type of food. They're rich in fiber and ellagic acid, a substance recently in the news for its possible anti-cancer properties. But it's hard to find fresh blackberries without camping out in the produce section.

That may soon change, due in part to the recent discovery that “Navaho,” a thornless blackberry variety, has a shelf life of 14 to 21 days compared with the typical 3- to 4-day shelf life of other varieties. Short shelf life is the reason for the scarcity of fresh blackberries, even though acreage devoted to blackberries has been expanding, especially in the South.

Navaho was bred by James N. Moore and John R. Clark of the University of Arkansas at Fayetteville and released in 1988 as the first thornless erect blackberry. But the discovery of its unusual staying power is more recent, the result of post-harvest research on blackberries by Penelope Perkins-Veazie, a plant physiologist with the Agricultural Research Service in Lane, Okla.

Perkins-Veazie stored Navaho blackberries in industrial coolers exactly like those used by industry before transport to stores. She sent a test shipment of the berries to the Netherlands and found they arrived just as they were picked: firm, exceptionally sweet and consistently tasty. This test included a 4-hour refrigerated shipment from an Oklahoma farm to Dallas/Fort Worth International Airport in Texas and a 2-day air shipment with dry ice.

The discovery of that Navaho's shelf life surpasses currently important commercial varieties and the latest breeding lines gives the fresh blackberry market a needed boost to convert a shrinking number of skeptics.

Scientific contact: Penelope Perkins-Veazie, ARS South Central Agricultural Research Laboratory, Lane, Okla., phone (405) 889-7395, fax (405) 889-5783, pperkins@ag.gov.