The Downing Centre Local Court has ordered the GMI Food Wholesalers and its directors to pay a fine of $236,000 for supplying Virgin Blue (VBA:AU) with inflight chicken meals tainted with the listeria bacteria that infected several passengers of the airline in 2009.

NSW Food Authority CEO Alan Coutts welcomed the verdict on Wednesday.

"This is an excellent result given the scope and seriousness of the charges brought against this company," Coutts said in a post on the NSW Food Authority's website. "The consequences of the incident have been serious for a number of people and this is never acceptable."

The court's ruling is considered unprecedented because it was the first time that bacterial DNA evidence was used in such a case, Coutts said.

Laboratory tests found the DNA of Listeria monocytogenes in ingredients in the pre-cooked chicken supplied to the food caterer of Virgin Blue and this caused 29 passengers to suffer listeriosis between December 2008 and June 2009. Those infected included two passengers who gave birth prematurely after falling ill, though they and their babies survived.

Listeria monocytogenes is the bacteria that causes listeriosis, whose symptoms include fever, headache, tiredness, aches and pains, diarrhoea, nausea and abdominal cramps. While healthy people are not vulnerable, those with weak immune system are prone to the illness, which, in worst cases, could lead to meningitis or septicemia.

GMI Food Wholesalers Pty Ltd and its directors pleaded guilty to a total of 26 charges under the NSW Food Act 2003.

The listeria outbreak in Virgin Blue passengers triggered a national public health alert. It also forced Virgin Blue to withdraw the chicken wraps by the end of June 2009. By that time, the tainted chicken meals had been served to passengers aboard Virgin Blue flights to east coast of Australia, to New Zealand and Bali, and out of Brisbane and the Gold Coast.