Why do people smash garlic?

Question

It seems a lot of people say to smash or crush a clove of garlic before they cut it up. Why is this?

I've cut up garlic both ways, and I could see crushed being potentially a little easier to handle since it's flatter and doesn't roll as much.

Answer

It has to do with the oils contained in the garlic. Garlic contains many volatile oils that are released when crushed or pressed. When garlic is smashed, the oils are forced out of the garlic and the resulting flavor is more intense and aggressive but these oils don't last long. When the garlic is left in larger pieces either chopped, minced or partially smashed, the oils are not forced out and they will slowly season your food as it is cooked.

In general, the longer the cooking time, the larger you can leave the pieces of garlic. Finely minced garlic may also be used in vinaigrette and salsas where the high acidity of the food will help break down the garlic and bring out its flavors.

As a rule, the more aggressively garlic is handled, the more aggressive and short-lived its flavor.

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