2. It is sanitary to purify oysters, but it is not foolproof.
3. The production environment of oysters is very important.
4. No seasoning can completely kill pathogenic microorganisms in oysters.
5. Don't abuse antibiotics to prevent problems.
Oysters are also called oysters, which is another name for oysters.
China is a big producer of oysters, with 70-80% of the global output in China. Besides raw food, barbecue, cooking and soup making, it is also used to produce oyster sauce and other by-products.
The most classic way to eat oysters is of course raw. Some people can't put it down, others refuse. The root cause is that raw food is unsafe.
In recent years, a product called "purified oyster" has gradually appeared on the market.
Merchants claim that only purified oysters are real oysters. Is that really the case?
Oyster is a bivalve shellfish, which belongs to filter-feeding animals, that is, algae and zooplankton in seawater are collected and eaten like a sieve.
One of the problems brought by this lifestyle is that it will also enrich the dirty things in seawater, such as sediments and microplastics.
Studies have found that there may be dozens of microplastics species in the digestive tract of an oyster.
In addition, it will also suck pathogenic microorganisms in seawater, such as Vibrio parahaemolyticus, Vibrio vulnificus and norovirus.
Sometimes it will be contaminated by other pathogenic bacteria, such as salmonella, during transportation, sales and production.
For example, Guangdong Province collected 290 oyster samples from 8 cities, among which the norovirus pollution rate was the highest in winter, reaching 30%.
In 480 oyster samples collected in Guangxi Autonomous Region, the overall contamination rate of norovirus exceeded 10%.
A farmer's market in Minhang District of Shanghai continuously monitored seafood for one year, and found that the contamination rate of Vibrio parahaemolyticus in oysters was the highest, reaching 54.4%.
Although it takes a certain amount to cause disease, the risk can not be ignored.
For example, according to the pollution of marine shellfish to Vibrio parahaemolyticus, Zhejiang CDC estimates that the number of people suffering from food poisoning caused by eating shellfish such as oysters exceeds 40,000 every year.
In order to solve these problems, the technology of "purifying oysters" appeared.
In fact, it is the same as shrimp, crab and shellfish after they are bought, but some processing steps are added.
Firstly, cultured oysters are moved into purified seawater, and then excreta and algae are removed by filtration of circulating water, soluble organic matter in water is removed by precipitation technology, and microorganisms such as bacteria are killed by ozone or ultraviolet rays.
Usually, after more than 24 hours of purification, the number of pathogenic bacteria will be greatly reduced, which can meet the raw food standards of the European Union.
The safety factor of purified oysters is obviously higher than that of unpurified oysters, but it is not absolutely safe.
For example, official website's question and answer about oysters from the FDA of the United States shows that a small amount of Vibrio vulnificus it carries can pose a fatal threat to patients with liver disease, diabetics and immunocompromised people.
In 20 12, the European Food Safety Agency evaluated the norovirus pollution in oysters, and they also thought that the existing purification methods (including purifying seawater pools) could not effectively eliminate the risk of virus infection.
In addition, there are some problems that purification technology can't solve.
The nature of oysters is attached growth, so the quality of oysters depends on the water quality of the culture environment.
If the aquaculture sea area is polluted by domestic sewage or industrial and agricultural sewage, oysters are easy to enrich heavy metals, pesticide residues and organic pollutants.
If the water is eutrophic, oysters will also be rich in algae toxins.
These are all difficult problems to be solved by oyster purification technology, so the origin of oysters is as important as "purifying oysters".
But even the best bay can't guarantee the absolute safety of oysters.
Take France, which loves food, as an example. According to public information, from 20 16 to now, the "EU Food and Feed Rapid Warning System" has issued 87 warnings about oysters, of which 67 were French oysters, most of which were contaminated by microorganisms such as norovirus.
In other words, even high-quality oysters may make you vomit and diarrhea.
Interestingly, oyster lovers don't seem to care about these things, and they are quite persistent in "repeated defeats and repeated wars".
At that time, oysters from the Gulf of Mexico caused many food poisoning incidents in the United States, and the FDA even considered banning the sale of oysters in the warm season.
As a result, not only did the industry jump out against it, but consumers actually didn't buy it.
Sure enough, in the face of delicious food, food safety is really not so important.
In short, it is not recommended to eat oysters, whether purified or imported.
If you must eat, try to choose purified oysters from good places.
In addition, no matter what seasoning you use, you can't kill the pathogenic microorganisms inside the oysters.
In case you feel unwell after eating, please seek medical advice promptly. You don't need antibiotic treatment at ordinary times, just rehydration and rest in time.