Tomato vaccination being tested to check salmonella

June 14th, 2008 - 12:14 pm ICT by IANS  

Toronto, June 14 (IANS) With salmonella outbreaks in tomatoes causing panic among consumers in the US and Canada, a new research has found a way to vaccinate tomatoes against the contamination. Keith Warriner, a professor at the food science department of the University of Guelph near Toronto, has pioneered a method - fighting microbes with microbes - to eliminate salmonella by treating tomatoes at the flowering stage.

“Because salmonella can become internalised in tomatoes, simply washing cannot inactivate or remove the pathogen. Preventing contamination of the tomato during cultivation and post-harvest is also problematic,” said a university statement quoting Warriner.

The five-year research led him to conclude that the solution lies in treating tomatoes at the flowering stage.

Warriner began his research by examining the types of bacteria that existed on tomatoes and found that the fruit having enterobacter bacteria were free from salmonella.

To learn how enterobacter killed or countered salmonella, Warriner carried out an experiment on mung beans since they take only days to grow compared to tomatoes.

He inoculated the beans with salmonella as well as enterobacter and found reduced levels of salmonella contamination, thus proving that enterobacter countered salmonella but not fully.

In the next experiment, he used enterobacter in combination with a virus called bacteriophage and found no salmonella in the sprouts of mung beans.

Warriner said his next experiment is to use this combination on tomato flowers.

“We know that if we have salmonella on the flowers, chances are good that it will contaminate the fruit that develops,” he said.

Warriner said he was working on developing a spray that combines enterobacter and bacteriophage to eliminate salmonella.

“The solution could also be introduced to the water tomatoes are transported in during the post-harvest stage, effectively cutting off all possible routes of contamination,” he said.

Tags: , , , , , , , , , , , , , , , , , ,

Posted in Sci-Tech |