Snack foods, ice cream, breakfast cereals
Air is by far the cheapest food additive, and perfectly safe. Extruded snack foods such as Cheetos, breakfast cereals like Kix, and inexpensive ice creams are fluffed out with air. In the ice cream world, the amount of air whipped into the final product is called overrun. Ben & Jerry's and Häagen-Dazs vanilla ice creams weigh more than 100 grams per half cup (120 grams), so they contain roughly 20% air. Breyers vanilla ice cream weighs 67 grams per half cup, with about 45% of the volume being air. That's one reason why the premium ice creams are higher in calories—they contain more actual ice cream per serving—and why the cheaper (and lower-calorie) ice creams are, well, cheaper.