* "Good" and "bad" are subjective: What makes a fish good for one person might not be good for another. Some people prefer certain species, while others prefer certain sizes or freshness.
* Visual inspection is limited: While some signs can indicate spoilage, they're not foolproof.
* Internal factors matter: The quality of a fish depends on factors like how it was caught, handled, stored, and prepared, all of which are invisible in a sample.
Instead of "good" and "bad," here's how to assess a fish sample for quality:
1. Look for external signs:
* Freshness:
* Eyes: Clear, bright, and bulging. Cloudy, sunken eyes indicate spoilage.
* Gills: Bright red and moist. Grey or brown gills mean the fish is not fresh.
* Skin: Shiny and smooth. Slimy or discolored skin suggests spoilage.
* Smell: A mild, fresh ocean smell is normal. A strong, ammonia-like odor indicates spoilage.
* Flesh: Firm and springy. Mushy flesh signifies spoilage.
2. Consider your purpose:
* Cooking: Different species and sizes are better suited for different cooking methods. Research recipes and cooking techniques for the fish you have.
* Scientific study: If you're examining a fish for scientific research, your assessment will depend on the specific research question.
3. Professional assessment:
* Fishmongers or seafood experts: They have the knowledge and experience to assess fish quality.
Remember: It's always best to buy fish from reputable sources to minimize the risk of consuming spoiled fish.