Blanching

In Cantonese cooking, this technique is used extensively with food that can be ruined by overcooking. Examples include greens, live shrimp, squid, cuttlefish, and some noodles.

Blanching is also often used before preserving food by canning or freezing, to quickly stop enzyme activity that would degrade the flavor or structure of the food item. Similarly, blanching can be used to lock in a bright color of some vegetables (like broccoli) before cooking using another technique, like stir frying. Blanching can also loosen the skin of some fruits and vegetables (like tomatoes) to ease in peeling them.