The primary flavoring agent of Greek tzatziki sauce is garlic.
Tzatziki combines strained yogurt, grated cucumber, garlic, salt, olive oil, and usually vinegar or lemon juice. Dill, mint, or parsley may be added, but garlic supplies the sauce’s distinctive pungent aroma and savory bite.
The name is related to Turkish cacık, a similar yogurt-and-cucumber dish. Tzatziki is thicker because Greek versions traditionally use strained yogurt and carefully drained cucumber. It is commonly served cold as a dip, meze, or accompaniment to gyros, souvlaki, grilled meats, and pita.
A common mix-up is calling cucumber the main flavoring agent. Cucumber provides freshness and moisture, while yogurt creates the creamy base; garlic is the ingredient most responsible for tzatziki’s characteristic flavor. Recipes vary by region and personal taste, so some versions use only a little garlic, while others are deliberately intense.