There are several key points to consider when choosing fish to buy. Sight, smell, and touch are needed to assess the quality of fish, and you need to know what to look for in order to determine which are the best-quality specimens.
For optimum flavor, fish should be bought and cooked as fresh as possible, preferably when in season – you will find many fish species are interchangeable in recipes. Certain species are suffering from overfishing, so the sustainability of the fish should also be given consideration. If you are buying fish in advance of serving it, it is important to store it properly to keep it at its best.
Choose the finest, most fresh fish available – one that has a shiny eye and smooth, glistening skin. There are particular signs of quality all over the body of a fish, in this instance a brook trout, that are worth knowing before you buy.
Ideally fish should be purchased on the day you intend to cook it, but if you have to store it for a short period of time, proper preparation and conditions are essential for ensuring its quality and also its safety. You can store fish in the fridge for up to 24 hours, but if you intend to use it after that time, it is better to freeze it on the day of purchase.
STORING FISH AT HOME The temperature of a domestic fridge is usually set at around 5°C (41°F), but fish should be stored at 0°C (32°F), so when storing fish in the refrigerator it is essential to place it in the coldest part or to envelop it with ice. Load whole fish into ice and place fillets in containers set on ice. The procedure of commercially freezing fish is done skillfully and rapidly at a very low temperatures, but it is difficult to replicate this at home. Refrigerate fish in small quantities in double-layered freezer bags, with as much air extracted as possible and carefully sealed. Freeze the fish for no longer than 4–6 weeks.
FRESH VS. FROZEN A lot of fish are processed and frozen at sea for an ever-expanding market. Freezing fresh fish slows the changes that occur as spoilage takes place, and if correctly done, it can be impossible to differentiate between fresh and frozen. Fish classified as “frozen at sea” will have been prepared and frozen within a few hours of being landed, and so the flavor is often of high-caliber to fresh fish. Fish should always be defrosted before cooking. This should be done slowly, in a refrigerator – rapid defrosting can result in loss of moisture, which will ruin the fish’s texture.
You can purchase fish already prepared, but it will not be as fresh as buying a full fish. The volume of preparation required before cooking a fish revolve around on how you intend to cook it. Whole fish generally need gutting, trimming, and scaling before cooking, or you might prefer to skin and fillet it or cut it into steaks.