ERADICATING BACTERIA WITH STEAM AND ULTRASOUND

FOOD SAFETY: Each year millions of people suffer food poisoning caused by Salmonella or Campylobacter in poultry. A new Danish invention solves the problem

In as little as one second, a chicken can be made free of Salmonella and Campylobacter through the use of steam and ultrasound. The method is based on a Danish invention which could dramatically improve food safety.

“It sounds simple, but the combination of steam and ultrasound really is a stroke of genius,” says vice president Niels Krebs of consulting engineers Force Technology. The company has researched into ultrasound for many years and has found ways of exploiting it especially for the medico industry. Force Technology’s extensive knowledge of ultrasound was the background to its involvement in a number of experiments to decontaminate liquids using ultrasound.

Dramatic improvement
“Those experiments were not that successful,” says Krebs. But they did lead to a discovery.

“Many different types of foods are steam treated to eradicate surface microorgan-isms. But while the method is reasonably efficient, it is not wholly effective,” says Krebs. “If the steam is used for as long as is necessary on for example a chicken, the result would be closer to a cooked chicken than a fresh one. That is because a laminar boundary layer forms between the steam and the surface, which to some extent protects the microorganisms present in the skin. But we discovered by simultaneously exposing the chicken to ultrasound, that the excitation of the air molecules disrupted the boundary layer. The steam could now penetrate properly and eradicate the bacteria. A treatment time of just one second can dramatically reduce the bacterial population on the surface without adversely affecting the product,” says Niels Krebs.

Full-scale testing
Force Technology has patented the new method of killing Salmonella and Campylobacter under the name SonoSteam.

The method has now been further refined, and the first full-scale tests will commence in mid-2007 in collaboration with a Danish poultry abattoir. Linco Food Systems, a world-leading manufacturer of processing equipment for poultry abattoirs, is building the module which will be installed in the processing line. Niels Krebs reckons that the first SonoSteam processing modules for poultry abattoirs will be ready for marketing early in 2008.

http://www.sonosteam.com

The Danish Veterinary and Food Administration has calculated that a 100-fold reduction of Campylobacter in poultry will result in a 25-fold reduction in the number of food poisoning cases. In tests on Campylobacter infected poultry, SonoSteam reduced the bacterial population by 99.9%, corresponding to a factor of 1,000 At a European level, the EU estimates that food poisoning caused by Salmonella and Campylobacter costs society EUR 2.9 billion in treatment and lost production. In 2006, 18 people in Denmark died after eating poultry infected with Campylobacter. More than 3,500 cases were officially registered by the Danish health authority. But that is only the tip of the iceberg. It is estimated that a total of over 90,000 people have been affected without seeking treatment. This costs society a fortune in treatment and lost working hours.