by Bee Wilson
One thing has changed, though. The science of “authenticity,” at the level of both detection and deception, has been transformed since the 1850s. There will always be room for organoleptic tests—those basic techniques of sniffing, examining, and tasting—but if they are to stand up as “evidence,” they must be backed up with sophisticated scientific experiment. The microscope, which did such sterling service for Hassall, has been largely superseded. It is still used occasionally when analysing such things as fruit jams and purees—under the microscope, it is easy to see if pears or rhubarb have been used to bulk out expensive berries, because the hard, stonelike cells of pears and the long, fibrous cells of rhubarb differ from the soft fruits. Mainly, however, microscope work has been replaced by gas chromatography, isotope analysis, and mass spectroscopy, among other methods.
Gas chromatography is a series of techniques for separating mixtures, where a sample is vaporized and passed through an inert gas in a column; a “detector” is then used to reveal the makeup of the substance, which comes out on a moving graph, like a heartbeat. Chromatography is an excellent tool for detecting the rising fraud in olive oil.26 The popularity of the “Mediterranean diet” has led to increased demand for Extra Virgin Olive Oil (EVOO, as some chefs now insist on calling it), which has given rise to the practice of diluting it with bog-standard refined olive oil. Armando Manni, who produces some of the best olive oil in Italy, has complained that much of what passes for “virgin olive oil” is no better than “lamp oil,” repackaged with fancy labels. Chromatography can detect this fraud, by isolating the sterol content of a given sample of oil. Refined oils have much higher levels of erythrodiol than do virgin oils.
For foods whose identity is closely linked to a particular environment, the best tool for establishing authenticity may be isotopes. “Locked in every plant and animal is a chemical memory of the weather and environment it grew up in.”27 Like the rings on a tree telling us about the plant’s age, isotopes can give us information about where and how a food was produced. Isotopes are different versions of the same element, with different atomic weights. By looking at the isotope ratios of the biological elements (carbon, hydrogen, oxygen, and nitrogen) in a given food using mass spectrometry, it is often possible to say where it came from or how it was produced. For example, you would expect to see a lot of lightweight hydrogen isotopes in English lamb and a lot of heavier hydrogen isotopes in Spanish lamb, because of the different chemistry of the ground or rain water drunk by the animals in the two countries. Isotopes can reveal what food a chicken has eaten (is it really corn-fed, as the packet claims?), whether salmon is wild or farmed, whether Parma ham truly comes from Parma, and whether honey from a particular area of the world has been adulterated with sugar or corn syrup.28
Isotopic measurements have also been used to detect the common scam of bulking out fruit juices with water, sugar, and pulpwash, a liquid extracted by repeatedly washing the exhausted pulp left over from making proper juice. In the early 1990s, it was calculated that fraudulent juices made up as much as 10 percent of the U.S. market. In Britain, a study done in 1991 found that sixteen out of twenty-one leading brands of orange juice contained added substances, mainly beet sugar, whose isotopic composition is similar to that found in oranges. Spectroscopy—which measures the molecular mass of a given sample—can show peaks in the sugar level of orange juice. By itself, however, this tool may not be enough. After all, oranges in nature vary in their sugar content. Food analysts may need to combine a number of techniques to come up with the “exquisitely sensitive assessment” they need.
One of the most “exquisitely sensitive” of all current tools is the use of DNA, which Woolfe’s programme has pioneered. He compares this kind of “food forensics” to “the DNA profiling of criminals,” the difference being that profiling food is “much more difficult.”29 With food, it is not the criminal but the crime that is being profiled, and the method has to be reworked for every different food. DNA analysis doesn’t work for everything—it is not much use for uncovering the kind of chemical mixtures exposed by Accum—but it is outstandingly good at detecting any fraud to do with species. As Woolfe has written, “DNA has the discriminating power because ultimately the definition of a variety or species is determined by the sequence of its genome.” This is useful because this kind of fraud is on the rise. Discerning eaters increasingly choose which foods to buy based on specific strains and breeds—Cox’s apples, Gressingham duck—which means that sly swindlers will increasingly try to pass one variety off as another. Now, the genetic “fingerprint” of different apple varieties can be recorded, making fraud harder. In 2003, the FSA did a survey of potato varieties. The British shopper will pay more for certain types of potato, such as King Edward, which are the classic floury English potato with a creamy interior, or Charlotte, which are yellow and waxy. A total of 294 samples were obtained, of which 33 percent were mislabelled and 17 percent were not the variety of potato they claimed to be. Many of the “King Edward” potatoes were actually Ambo potatoes, a variety that sells for half the price. It was possible to obtain this information only by doing a molecular genotyping of the relevant potatoes. The technique is so powerful, it can distinguish between fifty different commercial varieties of potatoes using only five DNA markers.
Similarly, the agency’s programme has come up with a DNA method for detecting the deliberate adulteration of durum wheat pasta with bog-standard common wheat. This could become a major problem throughout Europe, since the price differential between the two types of wheat is large. Proper dried pasta should be made using only durum wheat, whose hardness gives pasta its lovely al dente bite. Ordinary wheat flour makes flabby, sticky pasta, but it is much cheaper than durum wheat, so falsified pasta is common, especially in the lowest price range. Previously, there had been no accurate method, other than tasting, for checking for the presence of common flour in pasta. Scientists funded by the agency have worked out a way of amplifying a small sequence of DNA on the D-genome of common wheat; this genome is lacking in durum wheat. With this “assay,” it should now be possible to uncover even small additions of wheat flour to pasta. Elsewhere in Europe, researchers have used DNA testing to detect the presence of cow’s milk in “buffalo mozzarella” and in sheep’s milk cheese.
As for Woolfe, his greatest DNA triumph has been Basmati rice. It is generally acknowledged that Basmati, grown for hundreds of years in the foothills of the Himalayas, is the finest long-grain rice you can buy. If you want to make the best pilau or biriyani, then Basmati is what you need. It is the most delicate and fragrant rice (the name Basmati comes from the Hindi word for fragrant); even when plainly boiled, it is a feast. Apart from its perfume, another special property of Basmati is its long, thin grain; when you cook it, it almost doubles in length, due to the special character of its starch. Inevitably, it is more expensive than ordinary long-grain rice, both on account of its superior qualities and because it is difficult to grow; Basmati plants are temperamental and low-yielding. The cheapest Basmati retails in British supermarkets for around £1 per kilo, compared with 50p for basic rice; the finest, brand-name Basmati costs more than £2 per kilo.
Genuine Tilda Basmati rice. When the British Food Standards Agency surveyed the authenticity of Basmati rice on sale in Britain in 2003, Tilda rice was found to be pure; many others were not.
In the 1990s, Woolfe and his colleagues (then working at the Ministry of Agriculture, Fisheries and Food, before the Food Standards Agency was established) suspected that there might be a problem with Basmati being padded with inferior rice varieties. The trouble was, there was no technology equipped to find out the truth. Because of Basmati’s irresistible perfume, Woolfe looked into the possibility of characterizing it using an electronic nose. Could adulteration be detected by getting such a “nose” to analyse the smell of the cooking water left behind when Basmati was boiled? This proved a dead-end for detecting mixtures. It turns out that different batches of Basmati, even when entirely
genuine, have different strengths of aroma. Some just have a naturally weak scent.
Then, in 1999–2000, scientists working at the University of Nottingham came up with a technique that Woolfe could use, employing similar DNA markers to those used when doing genetic “fingerprinting” of humans. The technology, known as PCR—short for polymerase chain reaction—uses enzymes to amplify a particular string of DNA sequencing.30 This gives a genetic snapshot of a given plant or animal. By looking at the patterning of a short DNA sequence, it is possible to distinguish one species from another, provided the right sequence is found. In the case of Basmati, the scientists at Nottingham screened a large number of DNA sequences before eventually narrowing it down to twelve markers, which could distinguish even closely related rice cultivators from each other with accuracy. The “assay” was also made quantitative, so that it could measure not just whether Basmati was adulterated, but how much non-Basmati rice was present in a given sample. At last, Woolfe had the “robust method” he needed to test how much Basmati swindling was going on.
There was still the problem of defining Basmati, however. Unlike the special PDO foods of Europe, the name “Basmati” has no protected status. In UK law, Basmati was simply a “customary name”—a name that consumers can supposedly understand without need of further explanation. This may be true in the mandis (or markets) of India and Pakistan, where wholesale buyers are so knowledgeable about the different grades of rice that they can identify the various strains of Basmati simply by chewing on a raw, unhusked grain, gauging its exact flavour. It is not true in the supermarkets of the West, where most ordinary consumers have little sense of what the word on the label means, beyond the fact that Basmati rice tastes nice.
Map of the Basmati rice growing areas.
Woolfe’s starting point was the generally accepted place of origin of the rice, which grows in the foothills of the Himalayas—in the Punjab, Haryana, and Uttar Pradesh regions of India, as well as the eastern Punjab of Pakistan. He soon found, though, that to attempt to pin down exactly which strains of rice count as Basmati was to stumble into the minefield of Indian-Pakistani politics. The Indian authorities recognize only six traditional, “true-line” strains (Basmati 370, Dehra Dun, Basmati 217, Basmati 386, Taraori, Ranbir Basmati). They differentiate these from the evolved or hybrid Basmatis—Pusa Basmati, Punjab Basmati, Haryana Basmati, Kasturi, Mahi Suganda. Since the Indian export trade to Europe is mainly in traditional varieties, they favour these over the newer hybrids. The Pakistani authorities, by contrast, recognize five varieties of Basmati, their main trade being in three modern hybrid varieties—Super Basmati, Basmati 385, and Basmati 198. So while the Indian authorities see hybrids as interlopers, in Pakistan they are “authentic.” Given the political friction between India and Pakistan, these seemingly trivial botanical preferences can become loaded with menace.
Woolfe, a mild man, was alarmed at having stumbled into this minefield of Indo-Pakistani bubbling tensions. In the end, for reasons of diplomacy as well as to avoid distorting either country’s trade, the FSA decided that it must recognize all varieties that had been approved by both India and Pakistan—the modern Pakistani varieties as well as the older Indian ones, with the proviso that they must have been bred from at least one “parent” of a trueline Basmati variety. All the recognized varieties needed to have the special long, thin Basmati grain, and that inimitable fragrance.
Now equipped with both a method and a definition, in 2003 the Authenticity Unit organized a survey through local authorities who gathered 363 samples of Basmati rice from shops all over Britain. The findings were depressing if not surprising: only 54 percent of samples were pure Basmati rice; the others all had cheaper rice mixed in. Thirty-one samples contained non-Basmati rice in excess of 60 percent—which means that they hardly contained any genuine Basmati at all. Given the price differential between Basmati and ordinary long-grain, someone was getting very rich from the adulteration. It was calculated that in 2002 alone, Basmati consumers were swindled out of more than £5 million. As Woolfe comments, “It wasn’t just UK consumers being cheated, but also EU tax payers being cheated.” For reasons not altogether clear, at the time of the survey, Basmati rice was subsidized as it entered the EU, to the tune of up to 250 euros per tonne. Thus, importing non-Basmati rice as if it were Basmati was a hugely profitable business.
When Woolfe’s survey of Basmati rice was published in 2004, listing the names and addresses of the suppliers, the industry was shaken. Two Essex-based companies were fined more than £8,000 each for selling “Basmati” that had been adulterated with between 55 and 75 percent non-Basmati rice; it was not so much the sum of money as the exposure that stung. More widely, the new surveillance has enabled a much more rigorous code of practice for the industry. The previous code of practice allowed for Basmati legally to contain up to 20 percent non-Basmati rice; this has been revised to 7 percent, still higher than Woolfe would like, but, considering the basic agricultural and handling practices in the countries of origin, it is a step in the right direction.
Now that they are aware of the existence of DNA testing methods, sellers are much warier about palming off non-Basmati rice as Basmati. They have also seen the benefits of selling the real thing: the status of Tilda Basmati rice was only enhanced by the survey’s confirmation that it was 100 percent Basmati. A spokesperson for East End Foods, another manufacturer to come out well, commented gleefully, “I feel this is one of the best projects the FSA has undertaken.” Meanwhile, the Basmati growers of India, who are mostly still smallholders who farm in the old-fashioned ways, have been emboldened by the new knowledge of Basmati’s DNA to petition the World Trade Organization for protected status for the name. This would help to arm the Indian growers against the threat of unwanted competition from new U.S. hybrids sold under the trade name of “Texmati,” a cross-breed of Basmati with American long-grain rice, which claims to be “the most widely recognized brand of aromatic rice in the U.S.”
It is easy to see why Woolfe says that “Basmati is one of our really big success stories,” a touch of delight in his voice. At the same time, there is little chance of him resting on his laurels. Already, in the few years since the DNA-testing method was developed, unscrupulous rice traders have changed their tactics to evade detection. In 2003–4, the main adulterants used in Basmati mixes were the non-Basmati varieties Sherbati and Pakistan 386. The agency’s “assay” was purposely designed so that these varieties could be easily distinguished from true Basmati. As a result, in a sly piece of biopiracy, some merchants have switched to Yamini and Pusa 1121, new hybrids that are genetically very similar to some of the approved strains and are much harder to pick up using the current DNA markers. New markers will have to be developed to take this into account; not impossible, but costly. By the time the new method is ready, the science of swindling may have moved on too, with yet more varieties of rice bred to fool the detectors. “It’s a moving beast,” says Woolfe. “The minute you come up with a method, people find ways around it.”
The best that Woolfe can hope for is that the method will do as much good as possible before it becomes obsolete. For this, the method needs to be disseminated far and wide and backed up with enforcement. Hassall was one of the first public analysts—the body of scientists who analyse suspicious food samples at a local level. One of Woolfe’s achievements has been to ensure that new DNA methods reach the public analysts so that they can be used in routine policing of the food supply. The original DNA assay for Basmati needed expensive equipment, which many public labs simply couldn’t afford. Woolfe’s Authenticity team therefore worked to create a series of cheap, portable “labs-on-a-chip.” Using fine capillaries on a glass plate chip, rice samples are passed through three different colours of enzyme gel, which show different repeat sequences of DNA. By selecting the appropriate markers, these mini labs can easily and accurately differentiate between the approved Basmati varieties and the fakes. Each test only costs a few pounds and can be p
erformed by a nonspecialist. The same technology is being adapted by the Authenticity programme to create mini labs for revealing different fish species and meat species, as well as the adulteration of fruit juices.
The quiet, behind-the-scenes food forensics of Mark Woolfe shows that in some ways things have not changed since the days of Accum. The battle against adulteration is still the fight of the science of detection against the science of deception. The battlefield has moved, though, from chemistry to biology; and from deceptions that were easy to explain, once exposed, to those so complex and technical that consumers may never fully realize exactly what they have been duped with or rescued from. Insofar as they are aware of food regulation, they may resent it, as an unnecessary intrusion. Food dangers that cannot fully be explained to the layperson raise their own perils. We risk creating a populace that moves from apathy to hysteria to apathy again, without ever developing what Mark Woolfe himself seems to enjoy: a cool appreciation of the blessings of eating authentic food.
Invisible Dangers and Scaremongering
In the nineteenth century, as we have seen, food laws were responding to threats that were terrifying and direct. There was nothing theoretical about the arsenic-laced lozenges that killed twenty people in Bradford in 1858.31 Modern dangers from food tend to be different. In the words of a lawyer, “Harm has become ephemeral and distant, not hard and immediate.”32 The threat of carcinogenicity, hovering over so much food, is almost impossible to connect with the daily act of eating. If you ate an arsenic lozenge, you keeled over more or less instantly. Now, you may eat thousands of supposed “carcinogens,” from burnt toast to pesticides and additives, over many years before you develop cancer; or you may be lucky and never get ill at all. There is another difference too. Then, food fear cropped up in specific epidemics of deceit. Now, it is so omnipresent it is comical.