In-Depth Explanation
Blanching is a fundamental technique in professional kitchens. The brief heat exposure deactivates enzymes that cause discoloration and texture breakdown, which is why blanched green beans stay brilliantly green while raw ones turn olive-drab. The ice bath (shocking) is equally important — without it, residual heat continues cooking the food. Blanching times are precise: asparagus needs 2-3 minutes, haricots verts 1-2 minutes, and tomatoes just 30 seconds (for peeling). Mastering blanching elevates simple vegetable preparations to restaurant quality.