It seems like all the black pepper used these days in recipes is supposed to be "freshly ground." Does it really matter that much? And do different kinds of pepper — like white or even pink — really taste that different?
— Nora C., via email
It isn't just peppercorns that are better freshly ground. All spices start to lose their potency once they've been crushed up.
That's why most serious cooks and culinary experts advocate grinding spices right before using, preferably after lightly toasting. The fact that pepper mills have become so common is reflected in many modern recipes.
When using different types of peppercorns — actually a type of berry — you won't notice just differences in color. Each does indeed impart its own flavor.
Black peppercorns (Piper nigrum) are the most common type. The berries are picked when just turning red but still underripe. They are dried until the skin shrivels and darkens.
White peppercorns come from the same species, but the berry is ripened and the skin removed before drying. White pepper often is used in light-colored foods and sauces because it isn't visually obvious but still lends some pungency.
Green peppercorns also come from soft, underripe P. nigrum, preserved through artificial drying or in water, vinegar or brine. These lend a fresh, green flavor as well as some pungency.
The exception to the species cited above, pink (or red) peppercorns are fruits from a different tree (Schinus terebinthifolius). Generally sweeter and more aromatic than p. nigrum, these often are used as a decoration or garnish on a plated dish. They also pop up in artisan cocktails.