Toxicity in fish can affect the freshness of the fish. Fish are known to contain toxins generally denied consumers although it still has a high fitness level. Mackerel with a degree of freshness that has somewhat decreased more acceptable to consumers than the bloated fish that are still alive, because people are more familiar with pufferfish as poisonous fish. Based on the type of toxins it contains, the fish can be divided into three categories, namely ciguatera, puffer fish and paralytic shellfish poisoning.
Ciguatera is a group of fish that have toxic or non-toxic properties quickly. This fish becomes toxic when consuming certain toxic feed, but be nontoxic back when the fish are not eating these foods. The problem is, we do not know whether this group of fish that were caught were in a state of toxic or not. Consumers who eat fish This group will be poisoned, because these toxins can not be destroyed by the high temperatures during ripening.
Puffer fish is a fish group more dangerous than ciguatera group, because it contains deadly poison. More than 50% of deaths experienced by consumers who eat fish this group. Actually, only a limited section of this fish that contain toxins, while other parts are safe for consumption. Japanese society is happy eating fish after removing the stomach contain toxins.
Paralytic shellfish poisoning is poisoning caused by eating shellfish group types. The types of these shells contain toxins as captured in waters containing high concentrations dinofagellata. The mussels were consumed dinofagellata will accommodate dinoflagellate toxins released in his body without his own poisoning. People who consume shellfish poisoning will experience such difficulty in breathing and can cause death. The venom was not entirely destroyed by the high temperatures during cooking shellfish.
Environment can affect the freshness of the fish as it relates to food availability, weather or pollution. The availability of food in an environment where her life would affect the freshness of the fish. Food can affect the taste and appearance of the fish. In addition, food can also influence the chemical composition of the flesh of the fish. Inadequate food situation will reduce the nutritional value of fish and thus will speed up the process of decay.
The quality of fishery products caught in hot climates better than fish caught in cold regions. Fish hot area is dominated by mesophilic microbes, so when stored in a cool place most of the microbes die. Thus, the hot areas are more resistant fish stored at low temperatures compared to fish caught in the cold waters. Weather affects the availability of food for the fish.
Fair weather will increase the population of plankton, while overcast conditions resulted in the opposite. Unfavorable weather can increase the growth of harmful plankton (red tide) thus affecting the quality of the fish. Fish caught in waters contaminated with organic material containing microbes more than the fish caught in the waters are less polluted. The shelf life of fish caught in polluted waters shorter compared to fish from less polluted waters.
It can be said that the fish caught in polluted waters is lower than fish caught in waters less polluted. In addition to organic pollutants, the high content of heavy metals in the water will affect the quality of fish produced. The types of shellfish that live in waters with a high content of heavy metals will grow larger, but darker flesh color making it less attractive.