A funny thing happened on Wegmans Food Markets' way to selling rolls of irradiated ground beef: the novelty of the packaging and its no-leak virtue may be driving more sales than the added safety.

The Rochester, N.Y.-based supermarket chain introduced irradiated ground beef in 1- and 3-lb. chubs in May 2002, adding hamburger patties in MAP packaging a year later. Based on focus group interviews with frequent purchasers, the chain determined the chub was a bigger draw for repeat purchases than the irradiation process. "That surprised us," confesses Wegmans' Jeanne Colleluori.

The functional benefits of irradiation contributed to 3 percent sales growth for the line. Irradiated ground beef now accounts for 6 to 10 percent of overall category sales, Colleluori says. Refrigerated shelf life of 21 days and the opportunity to "cook it the way you like it" are irradiation-derived benefits that consumers like, she adds.

Although USDA insists that the chain include instructions to cook the meat to 160