DNA is sought for in dishes too!

In the food industry, to prepare various meat-based products it is common to mix different animal species. This practise is allowed so long as the different species are indicated in the ingredients. This implies that on the label of a salami for example, the animal species that have been used, must be indicated clearly, in a decreasing order depending on the quantity of each species that is present.
The determination of the animal species present in a food product is carried out during food controls carried out by the Veterinary Police that has the duty of performing biological and chemical analyses with the objective of defending consumers rights.
A precise definition of the species is of great importance even considering the preferences of consumers who may express the need to know the animal and plant species present in a food product for health reasons, in the case of specific allergies to some kinds of meat, or the wish to comply with food limitations for religious reasons. Some religions prohibit the consumption of pork or other food products in certain periods of the year; thus, whoever wants to comply with these rules has the right to be protected and to trust what is written on the label.
Food frauds take into account practically all productive activities, from the sale of fish products to the preparation of canned meat. More often than one would think some valued and costly fish are substituted with other very similar species of lower cost, for example, small sharks are sold as dogfish or crab and lobster meat are substituted by similar but lower quality products.
The macroscopic identification, i.e. visual, of meats that are similar in colour and shape when they are frozen is extremely difficult. The same unreliability on identification can occur with fresh meat of some species. When controls are carried out by Veterinaries or by the Carabinieri in a slaughterhouse, in a fish market or even in a seed storeroom it is not easy to tell ‘with the naked eye’ if a product is alright and normal.
DNA analyses of animal and plant species using PCR have greatly helped and speeded up the control procedures of the Authorities on suspected food products. For example, food controls regarding the search of GMOs (in rice, pasta or vegetables) are now carried out with PCR techniques in all analysis laboratories.
Summing up, in these last years, methods that involve the use of PCR are developing fast. The main advantage of using PCR is represented by the possibility of copying fragments of target DNA with just a few bases, i.e. very short. In the field of the food processing, this capacity of identifying very small strands of DNA proves to be useful since in cooked and treated foodstuffs very small quantities of degraded, damaged and non-purified DNA are found.
Moreover, as far as other applications of PCR methods in food processing are concerned, it is greatly utilized to search for pathogenic micro-organisms (dangerous for Man and animals) in food and raw materials (milk, eggs): for example, E. coli, Salmonella, L. monocytogenes and other bacteria that can provoke sickness when ingested.  In these cases too, the search for DNA so as to identify the bacterium in a rapid and safe way, can be very useful in hospital structures to provide the most efficient cure to victims of food poisoning.

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