Ceviche

Ceviche's 'cooking' action occurs because citric acid from lime or lemon juice lowers pH below 4, denaturing proteins and producing the opaque, firm texture associated with heat-cooked fish. However, the acid cure does not kill parasites or most pathogens as thoroughly as heat does — Anisakis larvae and Vibrio bacteria can survive acid exposure. Peruvian ceviche, the canonical form, uses fresh lime, aji amarillo chili, red onion, and cilantro, with cure times of 5–15 minutes ('ceviche' means the fish is briefly acid-marinated, not traditionally 'cooked' for hours as in some interpretations). Regional variants include Mexican aguachile (extremely brief cure, almost raw texture), Ecuadorian ceviche with ketchup and hot sauce, and Caribbean conch ceviche.