The most important characteristic of a fish is its freshness – and the freshest fish is the one that has just been caught.
This article will guide you to be able to recognize characteristics of fresh fish and characteristic of not so fresh fish. It is very important to get yourself familiar with this so you will be able to buy good fish for your restaurant and to offer to your guests the best quality dishes at your place.
- The smell of fresh fish is specific to its origin (sea, lake, river, fish pond) and it is pleasant and neutral. Spoiled fish has an unpleasant, sharp smell of trimethylamine (bad fish) and rot.
- Eyes of fresh fish are bulging and shiny. Eyes of old fish are cloudy and sunken into the head.
- Gills and fins of fresh fish are moist. In old fish they are dry, covered with sticky slime, grayish-brown in color and smell bad. Healthy gills are of a nice, bright red color.
- Skin in live and fresh fish is moist, must be unharmed and have a naturally metallic glow. Scales must be tightly attached to the body. The surface of healthy, fresh fish must be tight and shiny so that fish slides out of your hands. Discoloration and cracked skin are signs of rotting fish. Old or bad fish has already started loosing its scales.
- Slime is equally distributed over the fish, it is clear and odorless. With bleeding, slime gets increased, murky and dirty and has a sour smell.
- The body of a fresh fish is firm and has a specific consistency and appearance. When pressed it should bounce back. Soft, grey and inelastic fish is old or bad.
- Belly of a live and fresh fish is shiny and undamaged, and the anal opening is tight. Anal opening of old and bad fish sticks out and is yellow-brown in color.
- The most important characteristic of fish in transport is its freshness – and the freshest fish is the one just caught. As opposed to other kinds of meat that require maturing, fish is best sold and eaten fresh, preferably killed right before being cooked. Transport of fresh fish is considerably expensive, which is probably the reason why in total fish and fish products consumption only 3% of fresh fish is used.
- Fresh fish is easily perishable. It is kept on ice 10-15 days or in coolers under the temperature of around 0°C. This fish is best to be cleaned and gutted immediately after being caught. Quality is best preserved by placing fish in shallow crates after the night catch, mixing it with ice and selling it the next day. Fish must be entirely covered with ice and the crate bottom must be permeable so the water can leak out. When keeping fish in freezers, temperature must not be lower than -4°C to -6°C, otherwise the fish freezes, large ice crystals are formed, tissue is damaged and quality reduced.
- For preservation and transport of deep frozen fish, boats must have necessary equipment and proper cooling procedures must be followed in all phases after the fish is caught. Healthy, checked and sorted fish of grade I is frozen at -35°C to -40°C, sold exclusively in a frozen condition. In order to reduce the drying of the fish during long-term storage, frozen fish is glazed by showers of cold water in a room where temperature is 12°C or by immersion in cold water. Conditions for preservation of frozen fish until it reaches the store is temperature of -25 to -30°C for fatty fish and -20 to -23°C for other types with relative air humidity of 90 to 95%. Frozen or deep frozen fish must not be kept in storage longer than six months. Expiration date must be regularly checked as well as the conditions and quality of frozen products.
- Defrosting of frozen fish is best done in water at a temperature of 10°C do 15°C, which compensates for the loss of moisture and returns the products their freshness and juiciness.
Defrosted fish of grade I quality:
- must not have a foreign or stale smell,
- must not have damaged skin,
- meat must not show signs of dryness, and after being cooked must have pleasant taste and smell, firm consistency and white, light to dark pink color, specific cto certain kinds of fish.
I hope that now you know how to tell if fish is fresh.