There's no direct chemical reaction between lime and seafood in ceviche. The process relies on acid denaturation, not a chemical reaction in the traditional sense.

Here's how it works:

1. Acidification: The citric acid in lime juice lowers the pH of the seafood.

2. Protein Denaturation: This acidification disrupts the protein structure in the seafood. This process breaks down the muscle fibers, leading to a change in texture, making the seafood firmer and opaque.

3. Flavor Transformation: The acid also reacts with the proteins and other molecules in the seafood, contributing to the unique flavor profile of ceviche.

Key Points:

* Not a "Reaction": This isn't a typical chemical reaction where new substances are formed. Instead, it's a physical process of protein denaturation.

* "Curing" rather than "Cooking": Ceviche is technically cured, not cooked. The acid denatures the proteins, making them safe to eat, but the seafood doesn't reach cooking temperatures.

* Importance of Freshness: Ceviche relies on very fresh seafood to ensure it is safe to consume.

So, while there's no chemical reaction in the strict sense, the interaction between lime juice and seafood is crucial for the process of ceviche making.