Fish tastes "fishy" primarily because of improper handling and degradation after it's caught.
Understanding the "Fishy" Flavor
The characteristic "fishy" taste often associated with seafood is due to the breakdown of trimethylamine oxide (TMAO), a compound naturally present in fish. This breakdown produces trimethylamine (TMA), which has a distinct, ammonia-like odor and flavor that we perceive as "fishy."
The Role of Trimethylamine Oxide (TMAO)
- Osmoregulation: Fish use TMAO to regulate their internal salt balance, especially in saltwater environments.
- Breakdown Post-Mortem: Once a fish dies, bacteria and enzymes begin to break down TMAO into TMA.
Factors Contributing to Fishiness
Several factors contribute to the development of a fishy taste:
- Time: The longer a fish sits after being caught, the more TMA is produced.
- Temperature: Higher temperatures accelerate the breakdown of TMAO.
- Handling: Improper handling, such as bruising or contamination, can speed up the process.
- Species: Some fish species naturally have higher levels of TMAO than others, making them more prone to developing a fishy taste.
- Storage: Incorrect storage such as keeping the fish at room temperature will quickly degrade the fish.
How to Avoid "Fishy" Fish
To ensure your fish tastes fresh and clean, follow these guidelines:
- Smell it: Fresh fish should have a mild, sea-like odor. A strong, ammonia-like smell is a sign of spoilage.
- Check the texture: The flesh should be firm and spring back when touched. Avoid fish with a slimy or mushy texture.
- Inspect the eyes (if applicable): The eyes should be clear and bright, not cloudy or sunken.
- Buy from reputable sources: Choose fish from reputable fishmongers or markets that prioritize freshness and proper handling.
- Store it properly: Keep fish refrigerated at 40°F (4°C) or below, preferably on ice, and use it within one to two days.
- Prepare it quickly: Cook fish soon after purchasing it.
Summary
The fishy taste is a result of post-mortem chemical changes, primarily the breakdown of TMAO into TMA. Proper handling, storage, and prompt preparation are key to minimizing this undesirable flavor and enjoying fresh, flavorful fish.
