Category Archives: Scientific American

Whisky Fakers

Whisky auctioneer Isabel Graham-Yooll was examining a seller’s collection in London last year when she noticed some of
the liquors were slightly off-color—and several bottles seemed a little too full. She called the police, who arrested the seller for fraud. If the case goes to court, prosecutors may be able to count on more than just Graham-Yooll’s knowledge of fine whiskies; emerging laboratory techniques could help identify the liquors in question.

Whisky researchers are finding themselves at the forefront of the burgeoning science of food fraud detection. The spirit is a handy test substance because of its complexity: its main components–water and barley or other cereals–and its production method create unique chemical and biological signatures. And the time whisky spends in a wood cask helps to impart its golden color and unique aromas. “If [a new testing] technique works for whisky, then we can be sure it works for other spirit categories,” says Shona Harrison, the analytical services manager of the Scotch Whisky Research Institute (SWRI) in Edinburgh, whose work is funded by several liquor companies. Harrison and other researchers are fighting food and beverage fraud on multiple fronts—from monitoring global trade data to adapting laboratory-detection tools for use in the field.

Fakes are often a response to sudden bursts of demand for a particular product. Counterfeit Scotch, for example, is most common in places where legitimate suppliers cannot keep pace with consumers’ thirst for the liquor. And in the past couple of years a New Zealand honey called mānuka experienced a spike in popularity that was followed by a glut of bogus mānuka on the market.

Slapping high-end labels on bottom-shelf commercial whisky, honey or other products primarily harms the owner of the high-end brand. But when fraudsters replace the product consumers think they are buying with something else altogether, it can sicken or even kill people; this happened in India last year when six people died and 30 more fell ill from methanol poisoning after drinking black-market liquor. Food fraud is also lucrative—criminals can pocket tens of thousands of dollars per shipment of counterfeit product, and the sentences for getting caught are much more lenient than those for trafficking illegal drugs.

Detecting bad batches of something already on store shelves may be too late. So food technologist Katharina Verhaelen of the Bavarian Health and Food Safety Authority and her colleagues developed software that monitors food-import data in Germany on a monthly basis and flags suspicious changes in product volumes or prices. The system helped to identify adulterated hazelnuts associated with a record price jump, Verhaelen’s team reported in the December issue of Food Control.

Researchers are also using media reports to help detect and track counterfeit food. In a study published in November, supply chain researcher Yamine Bouzembrak of Wageningen University in the Netherlands and his colleagues took a public health alert program called the Medical Information System (MedISys), which scans online news and records potential cases of food contamination, and repurposed it for detecting cases of fraud. As of late September, they had identified and confirmed 5,174 separate food-fraud incidents, Bouzembrak says, and were set to meet with several European authorities at the November FoodIntegrity Conference in Nantes, France. They planned to discuss incorporating the updated tool, MedISys-FF, into early-warning systems for food contamination.

As methods for monitoring food fraud in the market have developed, so has commercial technology for detecting it at the molecular level. At a conference in 2017 Harrison encountered a portable spectrometer—a device that splits light shone through a liquid into its component wavelengths and measures their intensities to identify compounds inside. The customized device allowed minimally trained users to measure trace levels of sugars that are useful for verifying a wine’s identity. Harrison realized she could also use it to help distinguish whiskies based on their chemical characteristics, a task that otherwise requires bulkier lab equipment. Harrison’s institute, SWRI, bought one of the portable spectrometers to complement its existing profiling abilities.

Chemist David Ellis and his colleagues at the University of Manchester in England, who collaborate with the SWRI researchers, are now developing other spectroscopic methods for profiling Scotch. Whisky producers and distributors “seem particularly interested in ‘through-bottle’ methods at the moment,” Ellis says. His group’s technology might someday allow anyone to quickly screen bottles and decide whether to send them to the whisky authorities for a full analysis or whether it is safe to buy and enjoy them.

First published in the December 2018 issue of Scientific American: [html] [pdf].

Oil in Your Wine

Every great bottle of wine begins with a humble fungal infection. Historically, winemakers relied on naturally occurring yeasts to convert grape sugars into alcohol; modern vintners typically buy one of just a few laboratory-grown strains. Now, to set their products apart, some of the best winemakers are revisiting nature’s lesser-used microbial engineers. Not all these strains can withstand industrial production processes and retain their efficacy—but a natural additive offers a possible solution, new research suggests.

Industrial growers produce yeast in the presence of oxygen, which can damage cell walls and other important proteins during a process called oxidation. This can make it harder for yeasts—which are dehydrated for shipping—to perform when winemakers revive them. Biochemist Emilia Matallana of the University of Valencia in Spain and her colleagues have been exploring practical ways to fend off such oxidation for years. After showing that pure antioxidants worked, they began searching for a more affordable natural source. They found it in argan, an olivelike fruit used for food and cosmetics. The trees it grows on are famously frequented by domesticated goats.

Matallana and her team treated three varieties of wine yeast (Saccharomyces cerevisiae) with argan oil, dehydrated them and later rehydrated them. The oil protected important proteins in the yeasts from oxidation and boosted wine fermentation, the researchers reported in a study published online in June in Innovative Food Science & Emerging Technologies.

Microbiologists are now interested in studying how and why each yeast strain responded to the argan oil as it did, says enologist Ramón González of the Institute of Grapevine and Wine Sciences in Logroño, Spain, who was not involved in the work. The oil may one day enable vintners to use a wider range of specialized yeasts, putting more varied wines on the menu. As for how the oil affected the wine’s taste, Matallana says it was “nothing weird.”

This story first appeared in the September 2018 issue of Scientific American: [html] [pdf].

Emission Permission

Mexico kicked off 2017 with a 20 percent spike in gasoline prices, driven in part by the phasing out of subsidies. Some consumers set fires at gas stations—a response that highlights the backlash countries can face as they stop subsidizing carbon-based fuels and start encouraging climate-friendly alternatives. Now the Mexican government and stock market are experimenting with a gentler tool for discouraging carbon emissions: cap-and-trade. Mexico, which in 2012 passed the developing world’s first climate law, is well placed to set an example for other developing economies looking to shrink their carbon footprints.
Continue reading Emission Permission

Soil in the Forecast

For several days in late September 2015, heavy rains soaked the earth surrounding the district of El Cambray II in Guatemala. On the first night of the following month, steep slopes, long held in place by thick, tropical tree roots, suddenly gave way, burying hundreds of homes in mud up to 15 meters deep. At least 280 people died.

Officials had warned residents for years that the area was at risk, but a mixture of poverty and mistrust leads some of the poorest people in Central America and beyond to build and live on marginal land. Still, residents of El Cambray II might have been willing to temporarily evacuate, if they had received a credible and precise warning. And if such warnings were available worldwide, they could help reduce the 3,000 deaths attributed to landslides every year. Continue reading Soil in the Forecast