Well-raised oysters | For your information

Oysters extract their nutrition from the water they filter, but they accumulate disease-causing microorganisms, microplastics or heavy ions when in polluted water. It is the opposite process, that is, the process of purification or purification, that is of interest today: oysters can be purified when they are placed in a sufficient amount of sterile water, and this is how oyster purification plants make them edible, such as oysters from unhealthy coastal areas. These stations consist of basins, a seawater store, and a device to sterilize the water using chlorine, ozone, or ultraviolet radiation.

More than fifty articles over the past three years have been devoted to this purge, but why this sudden interest? This is especially because countries such as India or China are today more concerned with the quality of the oysters they sell, having been farmed in more polluted or better monitored waters than in the past. But also because of the presence of these microplastics, which we are monitoring more and more; Global warming, to which oysters must adapt, and the emergence of new biological approaches, which are rejuvenating the study of oyster metabolism.

Proteomics is thus the dynamic study of all an organism’s proteins: by chromatography and mass spectrometry, we track the protein content of organisms when conditions change inside or outside the cell, which genes cause cells to produce. Modified, meaning they are chemically bonded to sugars, fats, or other chemical groups that change their function. Thus, the proteome contains much more proteins than the genome contains genes, and its monitoring provides information about the adaptation of organisms to environmental changes.

It is clear that we did not wait for the advent of proteomics to worry about oyster purification: for many years, Everemer’s studies have relied on rationally based French regulations, which allow gourmets to enjoy them with complete peace of mind. . However, climate change is a concern, especially since rainfall could significantly change the salinity of sewage ponds or “flush” these natural marshes used by oyster farmers.

Recent studies determine the extent of salinity variations that oysters can tolerate, depending on water temperature, the duration of the salinity variation, and the size of the oyster. For example, 72-hour purification operations with violent salinity changes should be avoided. Or again, the contents of copper, iron, nickel, manganese and lead are greatly reduced after only 48 hours of purification, but zinc resists. Water temperature does not greatly affect purification efficiency, but high salinity is suitable. All this new information will be particularly useful for breeders in clear areas, where regulations require a stay of 14 to 28 days: they will thus be able to better compensate for excess freshwater supplies in the event of heavy rainfall.