Laser device designed for Mars unmasks counterfeit honey
By David Szondy
February 13, 2013
When someone mentions counterfeiting, it brings up images of money, watches or DVDs. It certainly doesn't make honey spring to mind, yet honey smuggling and counterfeiting is an international problem involving hundreds of millions of dollars. In an effort to combat this, the European Space Agency (ESA) is funding a demonstration project to adopt lasers designed to study the Martian atmosphere, to detect fake honey.
The United States consumes 400 million pounds (181 million kg) of honey per year, of which 53 percent is imported. In recent years, smuggled and counterfeit honey has become a major problem in the US and the EU. Mainland China has been the source of large quantities of honey contaminated with lead and illegal antibiotics that is illegally transshipped through India and relabeled before going on. Some of this honey isn't even honey, but a mixture of a small portion of real honey adulterated with sugar water, malt sweeteners, corn syrup, rice syrup, jaggery, barley malt sweetener, beet syrup or other additives. Similar problems occur with other foods, such as olive oil, chocolate and saffron.
One way of identifying such smuggled and counterfeit honey is by pollen analysis, which can pinpoint its origin based on the flowers the bees visited, but the Chinese often ultrafiltrate their honey to remove these traces. A method less easy to dodge is to study the isotope ratios of the atoms that make up the honey. Different ratios indicate where the honey came from and its composition, so both smuggled and fake honey can be detected. Take a sample of the honey, burn a few milligrams and measure the isotopes of carbon dioxide that it gives off to get the answer.
The tricky bit is coming up with equipment for measuring isotopes that’s both sensitive enough for the job, yet portable enough that samples don’t need to be sent back to a central laboratory. The answer to this problem came from, of all places, Mars.
Seven years ago, Britain’s Rutherford Appleton Laboratory (RAL) began development of a laser that could be used to hunt for methane in the atmosphere of the Red Planet. The result was the laser “isotope ratio-meter,” which is sensitive enough for isotope analysis using tunable infrared lasers on very small samples, yet lightweight and compact.
“You take a laser, whose optical frequency or ‘color’ can be continuously adjusted, beam it at a gas sample, and detect the level passing through the gas,” said Dr. Damien Weidmann, Laser Spectroscopy Team Leader at RAL Space. “Each molecule, and each of its isotopic forms, has a unique fingerprint spectrum. If, on the other hand, you know what you are looking for, you can simply set the laser to the appropriate frequency.”
Though it hasn't yet flown in space, the laser is being turned toward the identification of fake food through funding from ESA for a Technology Transfer Demonstration project.