The Wm. Wrigley Jr. unit of Mars is phasing out foil wrapping for most of its gum, according to a report in theChicago Sun-Times.Wrigley is transitioning from foil to paper for the individual sticks of its key brands, including Spearmint, Doublemint, Big Red and Juicy Fruit. The paper wrap is 13% cheaper than foil and will not compromise product protection or shelf life. The move, which began late last year for gum in paperboard cartons, will save an estimated 850 tons of aluminum a year. Wrigley will still use foil wrappers for its Extra and 5 gum brands.