Warning Signs of Fish Spoilage

A top priority for commercial fishermen is preserving their catch. Since they may not be returning to port immediately but moving on to other fishing spots, refrigeration and a well-insulated hold are vital in the effort to keep fish fresh. SEMCO/SEMCOLD LLC understands the importance of preventing fish spoilage, and we manufacture and install industrial cooling systems designed to customer specifications. In the commercial fishing business, proper cooling of the seafood product can mean the difference between expected profit and economic disaster. The warning signs of spoilage can typically be detected through the senses of sight and smell, but there are also other warning signs of fish spoilage.

Assessing the Quality of Fresh Fish and Warning Signs of Fish Spoilage

The term “quality” refers to the appearance and freshness of fish or the degree of spoilage that has occurred during the time of transport from sea to land. Though quality is something an individual can determine through sight and smell, food researchers have developed parameters that form the basis of an assessment tool known as the Quality Index Method (QIM). The various parts of a fish, such as the skin, eyes, and gills are rated. The QIM assigns a score of zero for very fresh fish and the numbers, or demerits, pile up as the fish deteriorates. Characteristics such as dull skin, cloudy eyes or a musty, sour odor are among the signs of fish spoilage. The QIM assessment has been used for many years by European and Nordic countries to evaluate how many days caught fish such as cod, herring, and flounder can be kept on ice while still remaining safe to eat.

Guarding Against Fish Spoilage

The hold of a commercial fishing vessel must be properly chilled in order to preserve the catch. Many types of insulation are available—polyurethane foam, fiberglass, cork board, even wood shavings—and SEMCO/SEMCOLD LLC can provide the accompanying cooling system depending on the kind of insulation selected, the size of the craft, the amount of space available, and the type of fish being caught. With the entire customized system in place, fishermen can go about their business, confident that there is ample protection against fish spoilage. The refrigeration equipment, coupled with the proper insulation, will maintain the correct temperature inside the hold.

Icing Down the Catch

Fish of good quality should have bright, shiny skin. Their eyes should be clear, their gills characteristically colorful, and they should carry a fresh, seaweed sort of smell. To ensure that they maintain good quality from the moment they are taken from the sea until the day of their delivery for packing and transport to a final destination, ice will be an important preservative. Ice, however, has its own issues. Since it is often handled with human hands, bacteria can invade the ice container, speeding up the spoilage process. SEMCO/SEMCOLD LLC offers ready-made clean ice that is available in several forms. Also available are icemakers that will produce ice continually as well as water filtration systems designed to ensure that the water used for the preservation of the catch is kept clean and organism free.

Different Kinds of Cooling for Best Preservation

Fish of different sizes have different needs relative to cooling methods. Small fish such as sardines and anchovies tend to spoil easily because they have few layers of protection. However, their small size allows for fast cooling. Medium-sized fish such as salmon, cod, or tilapia are less likely than smaller fish to spoil quickly and they stay cool longer than large fish. Meanwhile, large fish should ideally be gutted or filleted to make the cooling process more efficient. At SEMCO/SEMCOLD LLC, we understand these different requirements and stand ready to equip the commercial fishing industry with the ice, ice-making equipment, and refrigeration products they need to ensure the integrity of each valuable catch.