Captain America’s trademark red, white and blue shield appears near the 1 hr 30 min mark in the film at the point where Pepper Potts comes in on Tony trying to get out of his damaged armor. The line you want to watch out for is, ”Let’s face it, this is not the worst thing you’ve caught me doing.”
Marvel is also doing some Captain America cross-promotion in the Incredible Hulk movie. Read about that
HERE.