Black and white peppercorns are both the fruit of the pepper plant, but they are processed differently. Black peppercorns are picked when almost ripe and sun-dried, turning the outer layer black. To produce white peppercorns, this outer layer is removed before or after drying, leaving only the inner seed.
White pepper tastes hotter than black but is less complex, with fewer flavor notes, maria lorraine explains on Chowhound. High-quality peppercorns of either type are more aromatic and have more floral, spice, and fruit notes than generic ones. Candy recommends the pungent Muntok white and Tellicherry black peppercorns sold by Pendery's. Freshness is key to good white pepper, which turns stale and bitter faster than black, petradish says.
While black pepper is more common in American kitchens, using white pepper in light-colored dishes for aesthetic reasons (such as white sauces and mashed potatoes) is a tradition that originated in French cookery, FAL says. However, white pepper is also used in some cuisines for its specific flavor. It is common in Chinese cooking, and petradish also uses it in aromatic Vietnamese soups and pork dishes, as well as in many Swedish preparations.
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