Some researchers have found a way of depurating oysters so that the remaining bacterial counts in the oyster is minimal, and without sacrificing taste, texture and health of the oyster.
The process involves chilling the water to between 45 and 55 degrees Fahrenheit and sterilized it with ultraviolet light. Their method eliminated 99.9 per cent of the bacteria after four to five days. The oysters stayed alive during the purification, and their texture and taste were not altered.
Why shellfish can become deadly
AN adult oyster filters and cleans up to 190 litres of water a day.
They swallow algae, and remove dirt and nitrogen pollution.
Sometimes during the filtering process, bacteria can trigger norovirus which remains in the oyster.
Eating shellfish infected with a norovirus can lead to food poisoning with vomiting, diarrhoea and abdominal pain.
Noroviruses are the most common cause of viral gastroenteritis in humans.
The disease is usually self-limiting and severe illness is rare but it can lead to blood infections of people with compromised immune systems – especially those with chronic liver disease – and can cause severe and life-threatening reactions.
Sourced from – http://www.themercury.com.au/article/2013/04/03/375973_tasmania-news.html