Definition of fold in

The expression "fold in" has its origins in the world of baking and cooking. In these culinary contexts, "folding in" refers to a specific technique used to incorporate air into batter or dough without deflating it. Here's how it works: When mixing ingredients such as eggs or flour into a batter, it's important not to overmix, as this can result in a tough or dense final product. To avoid this issue, cooks will often "fold in" the new ingredients gently, using a spatula or whisk to incorporate them a little at a time. Instead of vigorous stirring, which can cause the mixture to lose its lightness and structure, folding involves lifting the batter from the bottom of the bowl and turning it over to gradually incorporate the new ingredient. The term "fold in" comes from imagining that you're folding a sheet of paper in half, creating a new, enclosed space. Just as you have to be gentle and careful when creasing the paper, so too must you be when adding new ingredients to a batter, working slowly and delicately to preserve the delicate structure you've already created. In the context of cooking and baking, then, "folding in" is important because it allows air to be incorporated into the mixture, creating a light, fluffy final product. But in broader usage, the expression retains its meaning of "incorporating a new element gently and carefully". By "folding in" ideas or perspectives, for instance, we can create a more complex and nuanced final product – whether that's a delicious cake or a groundbreaking new idea.