Garlic is a common food ingredient that is traditionally banned for royal occasions in some European cultures, including in British royal cuisine. This is because garlic has a strong, pungent odor that can linger on the breath for hours after consumption, which may not be desirable in formal social settings.
Other pungent ingredients such as onions, shallots, and chives are also sometimes avoided or used sparingly in royal cuisine. Instead, fresh herbs and spices such as parsley, thyme, and rosemary are often favored for their subtle flavors and aromas.
It is worth noting, however, that these customs and traditions may vary depending on the preferences of individual royals and the specific cultural context. In recent years, some British royal chefs have reportedly incorporated garlic and other formerly banned ingredients into their menus to reflect changing tastes and culinary trends.