So if ice cream is a foam, just how much air is there in the stuff? That all depends. It can be as little as 15% or as much as 50% depending on the brand. Who first thought to incorporate air bubbles into ice cream? Why, the very same people who’ve been obsessed with foams and mousses for hundreds of years. You know who I mean. Their turn-on’s include dairy, disco, Jerry Lewis and smoking. Turn-off’s: imported corn, movies with happy endings and anybody from Texas. Yes, that’s right, the French (partial credit will also be given to all those who said “New Yorkers”). It was the French who in the 17th century first discovered the importance of churning ice cream to keep its frozen, yet plastic consistency — probably via attempts to freeze some of their sweetened dessert foams. Of course, taking a foam like, say, whipped cream and freezing it is nearly impossibly without destroying it. But by chilling the same base mixture as it’s being agitated…ah, magnifique.