(fis.com) The National Institute
By means of a quick and reliable procedure, the new method can determine the level of this toxin in fresh and in canned fish. It can also be used in products from other food industries, such as red, white and sparkling wines, milk, cheese and fish meal.
INTI physical-chemistry laboratory in Mar del Plata developed a technique based on ELISA (Enzyme-linked immunosorbent assay) method to determine histamine in fish products using a microplate reader.
INTI scientists explain that the technique "relies on the use of immunogens, haptens or antibodies marked with an enzyme whose colourful product can be measured spectrophotometrically."
Researchers Carolina Spath and Guillermo Carrizo have ensured that this principle has the properties of an ideal immunoassay.
"It is versatile, robust, simple to apply; it uses economical reactive substances, has specificity between a reactive substance and an analyte, reproducibility of results, simplicity, speed and it offers the possibility of analysing several samples simultaneously," it has been pointed out.
Histamine poisoning is chemical poisoning due to the intake of foods containing high levels of this toxin. Poisoning caused by fish consumption is the most common because the microorganisms responsible for its appearance act when fish temperature is above 15 ºC.
This is why it is essential to maintain fish refrigeration temperatures from the moment the fish is caught until it is consumed to avoid the appearance of the enzyme that produces histamine.
This type of poisoning is known as scombroid poisoning because it is linked to the consumption of fish specimens of the families of Scomberesocidae Scombridae, such as tuna, bonito and mackerel. In addition, species like mackerel, anchovies and sardines can also develop high levels of histamine.
This toxin levels permitted in fish vary according to the criteria of each region. The European Community sets 100 ppm (parts per million) of histamine while the United States allows levels of up to 50 ppm.
In Argentina, the National Health Service and Food Quality (Senasa) stated that "the average value of a set of samples from the same lot for histamine in fresh fish should be below 100 ppm and no sample may have a higher value than 200 ppm."
The importance of determining the levels of histamine in fish is that this index is considered a quality criterion.