Topic for Jan. 10. ( Tue )

[Alex !]

Food science
- posted on the Guardian -

Can food forensics protect the sanctity of our plate?
Food crime hit the headlines in 2013 when the horsemeat scandal broke, but such fraud is not only common, it’s also hard to detect. Here, the authors of a new book reveal how vulnerable we are, and how science can keep us safe.

Back in January 2013, the unthinkable happened. Britain lost its appetite for frozen beef burgers. Sales plummeted, supermarkets were shunned and high street butchers sold record quantities of fresh mince. But this shift was no concerted effort to save our high streets _ it was an attempt to avoid being swindled. Because besides the expected beef, the supermarket patties contained horsemeat and pig meat too. And as the Food Standards Agency (FSA) confirmed that it wasn’t only burgers but lasagne, bolognese and even some diced meat that were affected, panic ensued. Politicians demanded answers, consumers demanded honest alternatives and, as the tangled, everyone demanded assurances that it would never happen again.

But it has, and it will. Indeed, Making profit by substituting expensive ingredients for cheaper ones is not a new phenomenon, probably dating back to when food first began to be traded. But it is the complexity of our current food system that has created more opportunities for criminals than ever before. Food processing methods allowing us to store, preserve and sell no-fuss food have also helped create a globalised and largely anonymous food network.

Consumer demand for low-cost, interesting and varied food available all year round means products can use many different ingredients from all over the world, Supply chains can therefore become impossibly complex and opaque, providing opportunities for those at home and overseas looking to make criminal profits from food. The huge sums of money involved can act as a powerful incentive.

As food scandals have become more preval‎ent, politicians have got wise to the problem. But calls for more coordinated and intensive monitoring as well as tighter legislation are easier said than done. Monitoring food fraud is not simple despite the hi-tech, CSI-style analytical methods available. Critically, many food frauds are highly calculated, using detailed knowledge of tests to slip under the radar of standard screenings.

Although food crime has been with us for hundreds of years, it has only recently been recognised as a specific criminal typology, The National Food Crime Unit (NFCU) is working hard with many partners to better understand the nature and scale of this offending and to help bring those responsible to justice. While there are vulnerabilities, food consumed in the UK is among the safest and most authentic in the world, and the work of the unit is about keeping it that way.

Doing so, however, takes more than a beady eye. In fact it takes what is known as a “fingerprint” _ a physical or biochemical characteristic _ that either confirm‎s the identity of the food or an adulterant. These fingerprints are like computer passwords _ the more symbols they contain, the more secure the password becomes. The most sophisticated fingerprints are found in alternative tests using simpler substances, such as fatty acids, sugars and pigments, may be needed to identify rogue ingredients. Additionally, the elements (carbon, hydrogen, nitrogen etc) that make up our foods give even more detail _ offering clues as to the geographical origins of different foods.

The diversity of food ingredients is matched only by the diversity of methods in which fraud can take place,” says Morling. “The many and varied testing methods available are a reflection of this. But there is no silver bullet. Defeating food crime is about more than testing products. Gathering intelligence from people is also vital.

Worryingly, it seems there are few foods that have not been tainted. From olive oil to fish, honey to tea and even those most hallowed of foodstuffs _ organic products _ betrayal lurks in our grocery bags. But researchers are fighting back with a scientific smorgasbord of their own.

Take a trip to a supermarket fish aisle and the problem with fish species stares you in the face. Or rather, it doesn’t. Consumer demand for perfectly portioned white fillets means that most fish is sold without heads, fins and skin, presenting opportunities to label cheaper species as more expensive ones. But the scam not only deceives customers _ passing off one fish as another provides a market for illegal, unreported and unregulated fishing.

Some mislabelling may be the result of confusion over the naming of species _ Atlantic cod has 58 different common names in the English language alone. Europe has tried to remedy this by requiring that scientific names be included on fish labels. This, along with improvements in self-regulation within the industry, is helping. Whereas studies five years ago showed mislabelling in up to 40% of samples tested in the EU, recent testing in six European countries showed only 4.9% were mislabelled.

This is a positive story, this can be linked to stronger EU legislation, but also increased awareness. The press have covered the issue of species mislabelling, making consumers more aware.

Spice crops may be vulnerable to climate change, resulting in lower yields and a greater temptation to “bulk out” products to meet demands. Whole spices or locally grown herbs are more trustworthy alternatives.

Corn oil was found nearly 20 years ago to be especially vulnerable to adulteration. Now purity can be assured due to a highly robust test based on the carbon isotope compositions of the fatty acid that make up the bulk of the oil. The maize plant used to produce corn oil has a different way of capturing carbon dioxide compared with all the other major vegetable oil-producing plants. This improvement in testing alone led to a significant reduction in fraud.

The trouble is that all of the different grades of olive oil have identical fatty acid compositions, which also overlap with other oils _ especially cheaper sunflower. While chemical tests provide some insights, the ultimate assessment remains the humble taste test. Technology, however, might yet save us.The future of olive oil testing is seen in e-noses and e-tongues designed to copy the discriminatory power of human olfactory systems.

What could be simpler or purer that a shining glass of golden honey? Almost anything, it turns out. Honey is in the top 10 of foods most likely to be adulterated _ a remarkable stat considering honey requires little or no processing in its production.

Not that the tinkering is particularly sophisticated. Honey is “stretched” with cheaper sugars, such as high fructose corn syrup, which has the same sugar composition as honey, thereby defying the most basic fingerprinting test.

Like olive oil, there are many different commercial variants of honey, and labels often claim specific plants and/or countries of origin. The classic case is the highly prized manuka honey, which is suspected of widespread adulteration based on production-sales volumes auditing. In the absence of GPS-tracked bees, scientists have had to turn to other methods to verify this breakfast-table staple, relying on a battery of tests including those based on stable isotopes, biochemical fingerprinting and DNA.

Verifying the identity of our comestibles is undoubtedly a challenge, particularly as more and more of us rely on processed foods. But there is a simple way to outfox the fraudsters. Buy ingredients with defining features and remember, you only get what you pay for _ so if it’s cheap the quality will almost certainly be compromised.