A pinch in cooking is a very small amount of an ingredient, typically salt, sugar or spice. Traditionally it was defined as "an amount that can be taken between the thumb and forefinger".[1] Historically the pinch was more precisely defined by some U.S. cookbooks as approximately 1⁄8 teaspoon.[2]
In the early 2000s some companies began selling measuring spoons that defined (or redefined) a dash as 1⁄8 teaspoon, a pinch as 1⁄16 teaspoon, and a smidgen as 1⁄32 teaspoon.[1][3] Based on these spoons, there are two pinches in a dash and two smidgens in a pinch.
One pinch of fine salt is approximately 1⁄4 gram (20–24 pinches per teaspoon), while one pinch of sugar is 1⁄2 – 1⁄3 = 1⁄6 gram.