In a highly critical report last month, the British government came under fire for what the Centre for Crime and Justice Studies said was a failure to tackle the problem of food poisoning, which results in 20,000 people being hospitalised and 500 deaths every year.
The thinktank blamed the worsening situation on a substantial fall in the number of food standards and environmental inspections over a decade between 2004 and 2013. The lack of inspections resulted in a cut in prosecutions, the thinktank said, and allowed sloppy procedures in the food industry to go unchecked.
Now scientists in South Korea have developed a laser that can now spot the presence of bacteria on the surfaces of food.This device could be used as an early warning system for consumers in the home and in restaurants, takeaways and grocery shops.
The researchers from the Korea Advanced Institute of Science and Technology (KAIST) envisage their laser will eventually be able to be used in a dongle attached to a mobile phone so that when people are shopping, they will be able to scan a piece of meat to see if harmful bacteria is present.
Professor Paul Park, the principle investigator on the project, said that the unit will also be able to be installed as part of a “smart” fridge that will then notify users when their food, both raw and cooked, is dangerous to eat or on the production line in a factory when meat is being processed.
The laser works by being pointed at pieces of food, both in and out of packaging, and recognises the movement of bacteria across the surface of the food.
One of the main advantages is that the laser is cheap and can, in theory at least, be retrofitted to equipment. Since the laser can read through packaging and cooked and uncooked food, its use could be relatively widespread.
When the red laser beam hits the biological tissue of the food, the reaction of the light to the surface – the scatter pattern – can be read. If there is bacteria present, this affects the reaction of the light and produces a different scatter pattern as they move around. A camera which takes images at a rate of 30 times a second is used to spot the differences.
This means that the laser can recognise when there is harmful bacteria present, and then warn the user of the phone, fridge or any other device in which it is housed.
“You can install this technique into your refrigerator because it can use very tiny laser diodes and images sensors which can be found in your smartphone and those are the only two important parts that you have to consider putting in,” said Park, who specialises in diagnosing disease using lasers.
So far, the technology has been able to detect the presence of Bacillus cereus and E coli. Bacillus cereus is a bacteria which causes food poisoning resulting in diarrhoea, nausea and vomiting. Feed infected with Bacillus cereus caused the death of three babies in 2014. Last November, the Chipotle chain temporarily shut 43 of its locations in the United States after an E coli outbreak.
The tests carried out by the Korean scientists started on chicken breasts, which were infected and then examined using the laser and camera apparatus. While the laser can detect the presence of both of the types of bacteria, it cannot distinguish between them in the early tests.
Because the equipment involved is relatively simple, it leaves a wide scope for how it can be used, he said. This could extend from an attachable dongle for a smartphone, which can be pointed at food while a shopper is in a supermarket, to one which is situated on a production line and scans food as it goes past.
“We can simply implement this technology into [the] smart phone. You only need the small laser diodes which means that when you go to the restaurant and you order the food and you are not sure this is safe, you can just tap. You can go to the grocery market and see the chickens and other food and you can [test] by yourself.”
Park and his colleagues now aim to commercialise the technology and have suggested that it could be part of a “smart” fridge within the next two years. A prototype device is currently being developed, which will then be put through trials. “I hope that within two years, we will see the smart refrigerator with this feature,” he said.