Laser Checks Food for Freshness
LUND, Sweden, Oct. 21, 2011 — Most packaged food products are protected from oxidation by a gas such as carbon dioxide or nitrogen. Currently there is no method that can check whether the packaging has the correct gas content, but a new handheld laser instrument that can detect oxygen levels in a nondestructive fashion could solve that problem.
“It will be the first nondestructive method. This means that measurements can be taken in closed packaging, and the gas composition over time can be checked. This will make it possible to check a much higher number of products than at present,” said Märta Lewander, an atomic physicist at Lund University.
Märta Lewander of Gasporox and Patrik Lundin, a Lund University doctoral student in atomic physics. (Images: Copyright Gunnar Menander/gmpp)
Lewander developed the method in her thesis and now works as chief technical officer for the company Gasporox, which is commercializing the technology.
The technique uses a laser connected to a handheld detector that measures the light coming out of the packaging and sends the data to a computer to be analyzed.
The product, which may be launched soon, could be used to check and improve the airtightness of packaging. Gasporox estimates that within two years, the method could also be used for quality control during the packaging process. In the future, retailers could also use it to check the shelf life of their goods.
The laser beam measures the amount of oxygen in packaged food products. Gasporox estimates that within two years, the method could be used for quality control at the packaging stage of production, and it could be used in stores to check the shelf life of goods.
The new laser detector can measure through almost all packaging materials, as long as some light can pass through. “Even packaging that contains aluminum foil, for example some fruit juice cartons, often has some part that is not covered by the foil,” Lewander said.
Research in the field is continuing at Lund University with a focus on measuring carbon dioxide in packaging. “It is important to measure both oxygen and carbon dioxide. Oxygen is most important, but there is also interest in carbon dioxide from the industry,” Lewander said.
The technology is based on a technique for measuring the gas composition of samples containing cavities. An early application was to diagnose sinusitis (inflammation of the paranasal sinuses, which may be due to infection) by enabling doctors to find out whether the sinuses were as full of gas as they should be. Clinical studies have confirmed that the technique works, and this application is expected to be on the market within a year or two.
For more information, visit: www.lunduniversity.lu.se
- laser detector
- Device that operates by interaction of incident radiation with semiconductor based material in order to produce an electrical signal orby other means, to interact with calorimetric devices which produce a thermally induced current. The response of the detection devices will vary by the source wavelength, intensity and energy.
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