Kraft’s shares were down 1.8 percent at $55.87 in after-hours trading. The company, which also makes Oscar Mayer meats and Kool-Aid beverages, said gross margin fell to 29.3 percent in the third quarter ended Sept. 27, from 33.8 percent a year earlier. At the same time, it has been offering discounts to boost sales at its meals and desserts business, where revenue fell 6.7 percent as consumers increasingly reach for healthier, organic food over desserts and processed items.