What Is Folding?
Folding is a gentle mixing technique that combines a light, airy mixture, like whipped cream or beaten egg whites, into a heavier one without deflating the air already whipped into it.
More detail
Instead of stirring in circles, folding uses a rubber spatula to cut down through the center of the bowl, scrape along the bottom, and turn the mixture up and over itself, rotating the bowl a quarter turn between passes. The goal is combining the two mixtures in as few strokes as possible, since every extra stroke knocks more air back out.
Where it's used
Used any time a recipe needs to protect a whipped component's volume, folding whipped cream into a mousse or no-churn ice cream base, or folding whipped egg whites into a soufflé or cake batter.
Substitutes
No substitute for the technique itself, but if you don't have a rubber spatula, a large metal spoon works almost as well, just use the same gentle scoop-and-turn motion instead of a flat blade that cuts straight through.
FAQ
What's the difference between folding and stirring?
Stirring uses a circular motion that's efficient at combining ingredients but knocks air out of anything whipped. Folding uses a scoop-and-turn motion specifically to combine two mixtures while keeping most of that air intact.
How do I know when I've folded enough?
Stop as soon as no large streaks of the unmixed ingredient remain. A few small streaks are better than overmixing, once it looks fully uniform, you've likely folded a few strokes too many and lost some volume.
