food deterioration
The food by their biological nature deterioration can occur through physical, chemical and microbiological. The deterioration can be biotic or abiotic causes the food is not suitable for consumption. It also affects the nutritional value, hygienic condition, nice appearance and organoleptic characteristics of food. The company is investigating Cebicheria where we find a great range of food, table (1), within the most outstanding are:
- Fish: Inadequate or poor hygiene which can be captured, preserved and stored the fish will directly interfere in fish spoilage. For example, if the fisherman catches the fish and leave it outdoors in the sun for several hours to reach the port, the food will suffer an impairment that is probably not visible to the naked eye. Well, there may be a nutritional loss, growth of microorganisms by high temperatures and poor maintenance, physical damage, and that is not protected and possibly the development of an activity enzimática.Por other hand, the organoleptic characteristics of food are affected when the fish is in a process of deterioration. This is due to the accumulation of products of bacterial metabolism.
- Seafood: The characteristics of the deterioration of seafood may also be observed in fish, as the following. Increased
content pH and hydrogen sulfide, ammonia. Increases
viscous layer on the surface, such as fins and gills. Lacks
shiny appearance and begins to fade.
Buy a brown, yellow or dirty.
Pupils and corneal clouding is opaque.
eyes will wrinkling and tearing.
galls become pale pinkish color.
muscles soften, expel a juice when pressed and pressed his fingers to easily sink the muscle.
Spine muscle can be separated easily.
Main causes of food spoilage
First, we have the processes and organisms that cause these alterations. Remember that microorganisms are unicellular, who can not be visible to the naked eye. These include bacteria, fungi, yeasts, parasites and viruses. Also, bacteria in the deterioration of tropical sea fish stored in ice, is composed almost exclusively of Pseudomonas spp. and S. putrefaciens which to rise to the appearance of a red color and aroma compounds. In general, shellfish are exposed to microbial spoilage rates similar to those of fish, however, refrigerated shrimp in the main microorganisms responsible for spoilage are species of the genera Acinetobacter, Moraxella and Glass.
First, we have the processes and organisms that cause these alterations. Remember that microorganisms are unicellular, who can not be visible to the naked eye. These include bacteria, fungi, yeasts, parasites and viruses. Also, bacteria in the deterioration of tropical sea fish stored in ice, is composed almost exclusively of Pseudomonas spp. and S. putrefaciens which to rise to the appearance of a red color and aroma compounds. In general, shellfish are exposed to microbial spoilage rates similar to those of fish, however, refrigerated shrimp in the main microorganisms responsible for spoilage are species of the genera Acinetobacter, Moraxella and Glass.
The presence of microorganisms is associated with: the temperature, which indicates the rate of decomposition of fish due to microorganisms increases with temperature rise l. The environment in which the fish lived, and which is subjected after the capture, it is very important for the type of microorganisms that can act and the conditions of their growth. Finally, the substrate and that being a food with high protein and water, is a very good substrate for the growth of microorganisms. That is, the microorganisms found in the tissues of the fish the food they need to reproduce. Also, the water activity, free water available in the food, it is important to know because while higher conducive to faster growth of microorganisms. Fresh fish is among the wet food and has a higher aw 0.85.
Second, the physical processes during capture caused significant physical damage often occur. These injuries continue to fish stored in bulk. This is compounded by dehydration losses on especially if stored for a long time on deck or exposed to wind and sun. Other major damage or injuries are cuts, trampling on the cover, transport and storage chain.
On the other hand, are chemical processes, which are changes caused for example by oxidation of fats in fish muscle, developing a rancid odor and taste. These processes are influenced by factors such as presence of oxygen, high temperatures, the more exposure (cut or filleted fish). Also, chemical reactions occur in the tissues of fish (proteolysis and lipolysis), substances that change the taste and odor.
Finally, enzymatic processes, we must remember that enzymes are substances that speed up chemical reactions, are found inside cells and the digestive juices. Remain active even after the death of the fish, causing irreversible changes in taste and texture in the fish muscle. There are three types of major changes due to the enzymes that trigger the rigor mortis, the breakdown of cells, changes in texture, aroma and flavor irreversible fish muscle.
On the other hand, are chemical processes, which are changes caused for example by oxidation of fats in fish muscle, developing a rancid odor and taste. These processes are influenced by factors such as presence of oxygen, high temperatures, the more exposure (cut or filleted fish). Also, chemical reactions occur in the tissues of fish (proteolysis and lipolysis), substances that change the taste and odor.
Finally, enzymatic processes, we must remember that enzymes are substances that speed up chemical reactions, are found inside cells and the digestive juices. Remain active even after the death of the fish, causing irreversible changes in taste and texture in the fish muscle. There are three types of major changes due to the enzymes that trigger the rigor mortis, the breakdown of cells, changes in texture, aroma and flavor irreversible fish muscle.
Food contamination
Fish: The fish are caught in open seas, are hunted using nets, hooks or traps. Sometimes that can take several hours fishing and caught fish must remain in the boat in contact with unwanted organisms. Also become prone to be contaminated by enteric microbial pathogens. Therefore, the fish should be protected from disturbance during the hours of fishing, where the plant would become procesado.Estas forms of pollution can occur in many ways, whether by human on board during evisceration operations and cleaning.
Fish: The fish are caught in open seas, are hunted using nets, hooks or traps. Sometimes that can take several hours fishing and caught fish must remain in the boat in contact with unwanted organisms. Also become prone to be contaminated by enteric microbial pathogens. Therefore, the fish should be protected from disturbance during the hours of fishing, where the plant would become procesado.Estas forms of pollution can occur in many ways, whether by human on board during evisceration operations and cleaning.
Mollusks: The organism that develops more abundantly and causes disturbance is Achromobacter. Then, there may be Pseudomonas and decreased Flavobacterium, Micrococcus and Bacillus.Por other hand, in the case of oysters, come to be kept in good condition at low temperatures remained alive in their shells, but if they die, fall apart easily. Also, the bacterial species that attack the oysters are the same as those mentioned above. This alteration is dominated "soured" because it is a proteolytic processing for their high% proteínas.Los be frozen or boiled shrimp as soon as possible after their capture, they are more susceptible to Moreover for bacterium contamination, shellfish tend to live in shallow waters near the coast, is where there are contaminated by sewage. Also the hands and utensils, as in the case of crustaceans pescados.Los must be handled with care when removing the shell and during preparation, as they are very susceptible to contamination by pathogens.
Main causes of food contamination: First we
physical contamination, which can be seen, for example, in some mollusks with shells containing traces of sand or stones inside . Second, chemical contamination that occurs when larger fish (tuna, fish, swordfish, shark) may accumulate throughout their lives amounts of heavy metals like lead or mercury in their diet and living environment. This makes them unfit for consumption. Other fish are toxic by nature. Sometimes, shellfish such as mussels or oysters contain marine toxins and cause serious poisoning. In the case of animals from aquaculture may also contain residues of veterinary drugs. Then we have the biological contamination within which we can distinguish three components: parasites, viruses and bacteria. Among the most common parasite Anisakis is a roundworm that causes cysts in fish tissue marine and seafood and in case of being eaten alive (raw fish) can cause serious problems in some people. This parasite is destroyed by cooking and freezing. In the virus can be noted that shell molluscs may transmit viruses such as hepatitis A, if they are raised in polluted waters. Inside you'll for the most dangerous bacteria are Salmonella, Clostridium botulinum, Vibrio, etc.. We should add a very important point to these sources of contamination, improper handling, which depends on the personal hygiene of each manipulator. For example, washing hands with soap and water is a fundamental fact either before starting work, every time you change activity during work, after using the bathroom, etc.. Another point are the hairs, which contain undesirable bacteria that break off and contaminate food. For this reason they must use either caps or hair collected. Others are those rings, which are excellent "dirt traps." There is accumulating bacteria can grow and then contaminate food. For this, you should avoid using them during handling. Finally, work clothes should be exclusively for food preparation. The clothes are a means of transport of microorganisms and dirt. Avoid the use of work clothes outside the area of \u200b\u200bfood preparation and should be washed daily.
physical contamination, which can be seen, for example, in some mollusks with shells containing traces of sand or stones inside . Second, chemical contamination that occurs when larger fish (tuna, fish, swordfish, shark) may accumulate throughout their lives amounts of heavy metals like lead or mercury in their diet and living environment. This makes them unfit for consumption. Other fish are toxic by nature. Sometimes, shellfish such as mussels or oysters contain marine toxins and cause serious poisoning. In the case of animals from aquaculture may also contain residues of veterinary drugs. Then we have the biological contamination within which we can distinguish three components: parasites, viruses and bacteria. Among the most common parasite Anisakis is a roundworm that causes cysts in fish tissue marine and seafood and in case of being eaten alive (raw fish) can cause serious problems in some people. This parasite is destroyed by cooking and freezing. In the virus can be noted that shell molluscs may transmit viruses such as hepatitis A, if they are raised in polluted waters. Inside you'll for the most dangerous bacteria are Salmonella, Clostridium botulinum, Vibrio, etc.. We should add a very important point to these sources of contamination, improper handling, which depends on the personal hygiene of each manipulator. For example, washing hands with soap and water is a fundamental fact either before starting work, every time you change activity during work, after using the bathroom, etc.. Another point are the hairs, which contain undesirable bacteria that break off and contaminate food. For this reason they must use either caps or hair collected. Others are those rings, which are excellent "dirt traps." There is accumulating bacteria can grow and then contaminate food. For this, you should avoid using them during handling. Finally, work clothes should be exclusively for food preparation. The clothes are a means of transport of microorganisms and dirt. Avoid the use of work clothes outside the area of \u200b\u200bfood preparation and should be washed daily.
Other aspects:
To prevent damage to the input, it should take appropriate conservation measures for each input used in the company. In the case of fish can be stored in different ways: frozen below -18 ° C, salted that gender is a salty dip in cold water to lose salt thus avoiding the risk of possible contamination by microorganisms. Another type is the smoke, where the fish are that under the action of the brine and further drying have been the action of wood smoke authorized.
addition, to avoid any contamination in the input, it should take preventive measures:
in primary production:
.
product selection. Analysis, washing and cleaning of
molluscs. Strict control of the treatments on farms
In transportation, receipt and storage:
. Visual inspection of fish at the reception. Checking the documentation, packaging and labels
. Refrigerate the fish with care and quality ice in cold
. Transportation vehicles
insulated or refrigerated. Strict hygiene control of transportation and storage
. Do not transport or store the fish along with other products
. Temperature monitoring of the cameras, as well as hygiene and health status
The processing :
. To implement a proper cleaning, disinfection and pest control
. Maintaining a high standard of personal hygiene. Also, surfaces and utensils.
Resources:
Food Microorganism 6, Microbial ecology of food, TA Roberts (Chairman), JI Pitt, J. Farkas, FH Grau Acribia Editorial, SA, 1998, Zaragoza, Spain.
Food Microbiology, DAA Mossel, B. Moreno and CB Struijk, Second Edition, Editorial Acribia, SA, 2006, Zaragoza, Spain.
Food Hygiene, Johns, Nicholas, second edition Acribia Editorial, SA, 1995, Zaragoza, Spain. CASP
Vanaclocha, APRIL Ana Requena, José (2003) Process of preserving food. 2nd ed. Madrid. Publisher: Oxford University Press
ADAMS, MR and MOSSS, MO (1995) Microbiology of food Editorial Acribia.
ADAMS, MR and MOSSS, MO (1995) Microbiology of food Editorial Acribia.
http://tematico8.asturias.es/export/sites/default/consumo/seguridadAlimentaria/seguridad-alimentaria
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