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We challenge you right now to briefly put down this book and find yourself something small and full flavoured that you can pop into your mouth (but don’t do it yet). A jellybean may not be the most nutritious option, but they work particularly well for this exercise. Now, when you’ve finished reading these instructions, put the book down, hold your nose and pop the jellybean into your mouth. KEEP HOLDING YOUR NOSE! Give the jellybean a good chew, swirl it around in your mouth and think about what flavours you are perceiving and then, while still chewing, let go of your nose and keep chewing for a bit longer. OK, now that you’ve read this, put down the book and do the exercise. We’ll wait for you ...
Welcome back. Hopefully, unless you’re anosmic (unable to smell), what you’ve just experienced is one of the most sophisticated pieces of equipment out there for conducting chemical analyses: the human sensory system. While we have stated over and over again throughout this book that most forms of food fraud are not detectable to the consumer, we would be remiss in completely ignoring this particularly economical and convenient piece of equipment that is, quite literally, right under our noses.
The human detector
The great science essayist, Lewis Thomas, wrote about smell: ‘To be sure, I know that odor of cinnamon or juniper and can name such things with accuracy when they turn up in front of my nose, but I cannot imagine them into existence.’1
Most of us find it easy to bring up an image of a bicycle in our mind or recall the sound of a bird call with enough accuracy to replicate it. And though we may be able to label a smell accurately when we detect it or even describe a smell with reasonable accuracy, we generally find it very difficult to recall a smell ‘into existence’ as Thomas so eloquently puts it. Yet olfactory cues are rather critical to our existence. On the most basic level they convey information that helps us make decisions that affect our survival – such as smelling smoke or whether a substance is toxic. Our nasal passages play a role in helping us choose the right sexual partner, avoiding sickness and, as is relevant to this book, selecting food. Beyond that, smells enrich our lives in ways that we probably can’t appreciate until the sense itself is removed.
Smells are made up of combinations of chemical odorants – molecules that evaporate and become airborne. The human olfactory system can detect and identify thousands of these odorants, and owing to our genetic makeup, cultural upbringing and personal experiences, two people can react very differently to exactly the same odorants.
When we breathe in, we draw chemical odorants into our nasal passages. These passages are lined with a thin sheet of mucus-coated sensory tissue, known as the olfactory epithelium. The odorant molecules get trapped in the mucus and make contact with olfactory receptor cells, which are nerve cells with a direct connection to the brain. The human nose contains hundreds of different types of olfactory receptors, whereas dogs may have over a thousand different types.
When the odorant molecule binds to one or more receptor cells, a biochemical chain reaction is triggered within the cell that causes a series of electrical pulses to be sent along the nerve fibres – known as axons – to the brain. The millions of axons from all of the nasal receptor cells are bundled together to form the olfactory nerve (the nose equivalent of the eye’s optic nerve).
This electrical signal, carried along the olfactory nerve, is sent to the olfactory bulb, which is a concentration of nerves located in the forebrain just behind and between the eyes. This is where the brain begins to process the information. The nerve endings of the receptor cells cluster together in regions known as glomeruli, which act as switchboards of the olfactory system. As the electrical signals come in from various receptors, this switchboard ‘lights up’ in unique patterns that are then processed by the olfactory bulb.
The olfactory bulb then passes this information on to the rest of the brain where it is processed further. The information goes to the limbic system – a part of the brain involved with emotion and memory – as well as the olfactory cortex and orbitofrontal cortex. It is this additional processing that scientists think is essential in forming lifelong memories, complete with emotion, which are connected with smells.
It’s commonly thought that humans have a relatively poor sense of smell compared with our fellow mammals. Evolution, after all, has reduced the size of our snouts as well as the number of genes that code for olfactory receptors. Rodents, for example, have 1,100 functional genes that code for olfactory receptors, whereas we humans have a mere 350. Does this mean that we have less capacity to smell our environment than the common sewer rat?
Not necessarily. Behavioural studies that test smell perception in humans and other primates suggest that we do as well as or better than other mammals.2 In fact, we can even outperform our canine friends and the most sensitive measuring instruments when sniffing out particular odours.3 Our 350 smell receptors are capable of detecting thousands of different odours, some with such sensitivity that we could detect less than a drop in an Olympic-sized swimming pool. One of the aromatic compounds in citrus for example, (Z)-8-tetradecenal, which, as you would have guessed, has a fruity, citrus-like odour, can be detected by humans at a threshold of 0.009 parts per billion when in water.4 So although we have fewer olfactory receptors than a common sewer rat, our post-processing of this information in our brains somehow compensates and gives us a diverse and sensitive understanding of odours.
There are numerous selective advantages to having a good sniffer. Bacteria and viruses – the root cause of many illnesses – can change the body’s chemistry directly or indirectly by eliciting immune responses. This is metabolomics at its core. These chemical changes might happen before a sick person becomes symptomatic. Perhaps their sweat or breath starts to smell different before they become feverish, for example. An ability to detect these changes in body chemistry at a time when the sick person is contagious but asymptomatic would be incredibly advantageous in avoiding illness.
There is evidence (scientific and anecdotal) to support this. Melanoma cells (cancerous skin cells), for example, produce compounds that aren’t detected in normal melanocytes (skin cells). These compounds – dimethyl disulphide and trisulphide – are released as part of the vapour signature associated with a melanoma cell, giving them a distinct smell compared with normal cells. In 2014, scientists from Sweden and the US infected healthy individuals with an endotoxin, large molecules found in some bacteria that trigger a strong immune response in animals.5 They found that within hours of being injected, individuals had a more unpleasing body odour relative to when they were exposed to a placebo. It was the first experimental evidence that an activated immune response is smelly, and that this can be detected by other humans so that they might avoid personal contact with affected individuals. Of course our use of deodorants, antiperspirants, perfumes and colognes mask all of these subtle cues these days.
As the jellybean exercise should have highlighted, our olfactory system is a crucial component of our ability to perceive flavours. The other major system, of course, is our gustatory system – our taste receptors. While our nose is the gatekeeper to determine whether to put something in our mouth, our sense of taste is what helps us decide whether to swallow it. The latest science suggests that humans can detect five groups of taste qualities: sweet, sour, bitter, salty and savoury (also known as umami). Not all animals can detect all these tastes – cats, for example, have been obligatory carnivores for so long in their evolutionary history that they have lost the ability to detect sweet flavours.
Each of the five taste qualities is stimulated by specific chemicals in the food. These chemicals are dissolved in saliva and then recognised by receptor cells in the tips of taste buds located in the mouth. Humans have about 10,000 taste buds, which are mostly clustered in small rounded bumps, called papillae, found on the surface of the tongue, though there are taste buds on the roof of the mouth, epiglottis and throat too.
When a taste receptor recognises a chemical stimulus – glutamate, for example, which is responsible for the broth-like umami taste quality – a series of biochemical reactions are triggered. Enzymes and hormones are released in the mouth, but the digestive system is also warmed up, knowing food is on its way. The receptor will also communicate with other cells within the taste bud, which translate the chemical information into an electrical message, much like olfaction. The electrical signal is carried along nerves to an area of the brain called the nucleus of the solitary tract (NST). Initial taste processing is done here and then signals are passed along to higher brain centres. It is there that this information is combined with smell information as well as chemical irritation, texture and appearance to define a comprehensive concept of flavour associated with the food, and then this information gets stored in our food reference database.
So surely this sophisticated sensory system is capable of detecting a little food fraud? We are, after all, capable of outperforming some chemical analyses. Where there are no varietal analyses for wines there are sommeliers who can, with repeatable accuracy, name the varietal as well as other descriptors of the wine. If you recall from Chapter 3, chemical analyses gave extra virgin olive oils a pass grade, yet the same ones failed the human sensory evaluations. Sensory panels are fine-tuned like any other analytical instrument. Individuals are given threshold tests to determine what their sensitivities are to certain chemical compounds. Then, with this information to hand, a panel can be carefully chosen that may be particularly sensitive to certain chemical compounds that are being sought out in the analysis, or alternatively, to make the panel as diverse as possible. The individuals are all trained to describe the flavour sensations they perceive objectively. They may taste hundreds of samples and have some familiarity with what compounds can create certain sensory experiences. They play an important role and will probably continue to do so in terms of food analysis. But what about those of us who have less finely tuned palates?
There is no denying that the average consumer is capable of detecting some forms of food fraud, not just based on smell and taste, but by combining that internal reference database we mentioned in Chapter 2 with all of our sensory inputs. When we open an envelope of saffron, does it smell like saffron? Does it look and behave like saffron? Does the fish fillet fall apart unexpectedly while cooking? Does the egg have a shell membrane when you crack it? And yet, people are being fooled daily by seemingly clumsy frauds.
With the exception of those that are anosmic, the downfall in the human fraud detection system does not lie in the equipment but in the reference database. The sensory system is there, but the database is sparse, or in some cases warped. As we mentioned in Chapter 1, a child that has been raised on foods with a synthesised strawberry flavour will still be able to tell a real strawberry from a fake one, but she will have learned a preference for the fake flavour. In her database, the compound ethyl methylphenylglycidate has been labelled as ‘strawberry’ while the cocktail of compounds associated with a real strawberry may be labelled as ‘strawberry (other)’. People who have only ever eaten commercially produced loaves of bread will have ‘seven to ten days’ listed under the ‘shelf life’ category in their database, while those who have baked their own bread will have ‘two to three days’. So if our databases for unadulterated authentic food are skewed, what chance do we have of recognising the fakes? If our brain is compensating for our olfactory receptor shortcomings, surely we must equip it with the information necessary for processing.
Technology to the rescue?
While we have far more superior noses than we give ourselves credit for, most food fraud is realistically beyond our sensory capabilities. With so many sophisticated analytical tests and so much technology available, is there any chance that anti-food-fraud devices will become available for consumers to conduct their own testing?
Perhaps we just need an unbiased electronic version of the equipment we already have. The quest for electronic noses and tongues has been going on for decades. Their allure is that they have the potential to be relatively cheap, relatively mobile and easier to use than other methods that examine volatile compounds. But as we described in Chapter 3, there have been challenges in achieving the same sensitivity and specificity as a human sensory panel can provide. Versions of these devices, particularly the electronic or e-nose, have found applications in the food and beverage industry. Most of these applications revolve around spoilage detection, which is likely because most human noses would probably rather avoid such smells. Fish spoilage, for example, has been thoroughly investigated using electronic noses – the volatiles produced as the flesh deteriorates are measured by the e-nose and compared with other observable changes such as colour change.
Researchers from Barcelona, Spain, have been developing an electronic tongue, which they first used to help discriminate between different types of cava wines and, more recently, types of commercial beer. They hope that eventually they will get it to a point where it can be used to help detect fraud – but, once again, it will depend on the type of fraud. Such devices will no doubt find applications within the food and beverage industry, but it’s unlikely that there would ever be a pocket-sized version for consumers. After all, how could it ever be cheaper and more convenient to use than our own nose and tongue?
Dreams of hand-held consumer testing devices stumble upon the same obstacles that the food analyst suffers when trying to battle food fraud: there’s a different test for every question. So while formaldehyde indicator strips can be purchased online and fit easily in a pocket or handbag, they only answer one question. The technology exists already to build a pregnancy-kit-like device to determine whether your swordfish is really swordfish, but again, it’s a single-use, single-question test. For now, the concept of a Star Trek-style tricorder that is a multifunctional hand-held device for detecting food fraud remains in the realm of science fiction, though perhaps advances towards such a device in the medical field might speed things along.
What we do see coming down the pipeline are new modes of delivering information about traceability. This is known as the food traceability tech sector and it’s estimated that the world market for such technologies will reach over £7 million (US$ 11 million) in 2015. Simply put, these are technologies that connect consumers with their food’s journey. The seafood industry seems to be working particularly hard at developing these types of technologies. We mentioned ThisFish and some other projects in Chapter 4, but there are others as well, many of which will be rolling out phone apps about the same time that this book is released. The hard work in these systems is building the database to support them. The technology is just a matter of a QR code and a smart phone – it’s tracking down the supply chain and building the story behind the food that’s the hard part.
One Degree Organic Foods in Abbotsford, Canada has developed such a system for their products. A shopper can scan a QR code on their product label or plug a six-digit product code into the One Degree website and trace every ingredient in that product back to its source. There are even videos of the farmers to give the customer a greater sense of their food and where it came from. It’s one of the first places to offer this to multi-ingredient products. What this means for the business, however, is that nearly half the business is devoted to the technology side of things.
The logical step for companies not willing or capable of devoting such resources to developing these types of technologies is to bring in third-party authenticity certification schemes. Robert Hanner and his group at the University of Guelph created a spin-out company, called TRU-ID, which uses DNA barcoding technology to authenticate food and natural health products. As consumers put greater value on the authenticity of their food, producers may gain a competitive advantage in having such certifications identified with their products. On the other hand, there is also the potential for abusing the certification, as we have seen with organic certifications.
It would seem, for now at least, that technology is not going to equip us with analytical tools that we can take with us to the supermarket. However, we should expect to see more of it in the very near future helping us get better connected to our food. Even as we write this last sentence, something seems wrong. We need technology to connect us with the stuff we grow in the ground? On one hand we think it’s wonderful to be better connected to our food and have tools to explore where it has come from, if for no other reason than that it forces retailers to audit their own supply chains. On the other hand, it feels not dissimilar to standing on a corner staring at your phone to find directions when you could simply ask someone. There are immeasurable and unexpected benefits of just talking to people.
Taking action
While we await the pocket version of the electronic tongue, there are other actions we can take as consumers to try and minimise our exposure to food fraud. In each of the chapters we have tried to provide advice specific to that type of food, but it isn’t always practical to apply it more generally. For example, buying fish with its head on is a good idea, but this doesn’t really work with other meat products (though there might be more vegetarians in the world if it did)!
Before we go further, however, let us just say that we are fully aware that buying food can be complicated. We may enter a shop with our moral compass directing us towards fresh, whole, organic, local and ethically sourced food. And then screaming children, loud-mobile-phone-talker guy, chatting ladies who won’t get out of the way, disgruntled I-don’t-get-paid-enough-to-know-what-chia-seeds-are employees, and what seems like a never-ending shelf restocking brigade all get in the way (sometimes quite literally). The next thing you know, you’re checking out with a bunch of ready-made meals, comfort food (aka chocolate and crisps) and highly packaged lunch-box items. None of it was on your grocery list and none of it resembles real food. The moral compass got lost somewhere in the frozen foods section and you feel guilty because you feel you have somehow let yourself, your family, independent grocers, animals, local farmers and the rest of the planet down because you made some poor purchasing decisions. And now you have to consider food fraud as well?
Relax. There are a lot of decisions to make around the food that we buy – price, nutritional value, taste, what your household will eat, ethics, sustainability and yes ... authenticity. Our priorities will change depending on our financial situation in that moment, who’s coming for dinner that week, how busy we are, what food scandal has hit the media lately, how hungry we are and what mood we’re in. That’s just life.
But information is a powerful tool and the more informed we are, the better decisions we can make. Estimates are that one in every ten items we buy in the supermarket is fraudulent in some way, so we need to go in there armed with whatever we can. So, in the interest of adding to your toolbox, here are some actions that may help reduce your vulnerability to food fraud.
Buy whole, recognisable foods. This isn’t always practical of course, but it is much harder to fake a whole almond than it is to add an adulterant to ground almonds. Fish fillets that have no recognisable features can easily be mislabelled as other species. Eat fruit whole or juice it yourself. Whole spices are not only less prone to fraud, they keep longer in the cupboard. This is probably the single most effective action we as consumers can take towards reducing our vulnerability to fraud and probably improving our diet at the same time.
Rein in the chain. If you buy whole recognisable foods, the food supply chain will naturally shorten. However, there are other ways to do this. Honey was the perfect example of this – find out where your local beekeeper is and buy direct. If you’re lucky enough to live near a farm shop or farmer’s market, take advantage of this as often as you can. If you don’t have a market, look into schemes that may deliver locally produced food in a weekly box. And don’t be afraid to ask retailers who they buy from or more generally what their supply chains look like.
Buy from people you trust. This doesn’t necessarily mean that you have to play poker every Friday with your local fishmonger. But it does mean that you should feel confident that if something was really wrong with your food – for instance, if it made your family sick – the person or retailer you bought it from would be able to provide you with quick answers about the product they sold you. Somewhere in our research we read that you can learn far more from the person selling you the food than you can from any label – sage advice indeed.
Don’t fall prey to unrealistic prices. We’ve seen over and over again that prices that seem too good to be true probably are. If you come across such deals, ask yourself how they’re possible. If you’re feeling particularly brazen, ask the retailer how such a deal can exist. How can a bottle of vodka be worth two quid? Food (not that we really consider vodka food) should not be cheap – be realistic about the cost of food.
Expand your internal food reference database. We all need to refresh (in some cases reboot completely) and expand our internal food reference databases. Learn how it is made but also go out into the world and explore food or take it home and experiment with it. This means experiencing our food. In this hectic world it is all too easy to wolf down some form of nutrition while on the move or at our desks. Mindless eating has to be one of the downfalls of our modern society. If we consider each meal as an opportunity to expand our database, perhaps we will take more time to understand and appreciate our food.
This is also where education plays a role. Chef Jamie Oliver is leading the charge in this area with the campaign Food Revolution Day. The goal is to make practical food education compulsory in the school curriculum, globally (nobody could ever call Oliver an underachiever). The motivation behind the campaign is to help children lead healthier and happier lives, while tackling the global obesity problem. However, there are potential side effects to this in that educating children about good food starts to build their reference database. Perhaps it even means that ethyl methylphenylglycidate gets reassigned with the label ‘fake strawberry’.
Find the story in your food. The criteria for choosing our food can sometimes seem overwhelming. Often this can be simplified by selecting food that has a good story. Let us give you an example. One story is: I bought some mature cheese from the supermarket. It wasn’t particularly mature-tasting, but it was on sale. A second story is: I popped into this cheese shop and started talking to the guy behind the counter (we promise this isn’t the Monty Python sketch all over again). He’s been making and selling cheese for 30 years. He took the business over from his mother when his older sister didn’t want it. He let me try a whole bunch of cheeses, but I told him I was really after something very sharp. You know, the kind of cheese that takes the skin off the roof of your mouth. So, he took me into the back where he ages his own cheese and cut off a piece of this round he had ... well, it was the best cheese I’ve ever had. Bought the whole round off the guy!
OK, so these are obviously two extremes, but you get the picture. We don’t realise how much we want to know the story behind our food until we get it. This is perhaps one of the reasons why Riverford Organics has been so successful in the UK. Each week, along with a box of food, there is a story about what’s happening at Riverford. And it’s not some gloss-over of what’s in bloom or how great the carrots are looking, though there’s some of that as well, obviously. It’s quite often the bad and the ugly stories, from the fields as well as the office. Details like ‘ten weeks of solid rain have meant that planting’s delayed so expect your lettuce to be a little later this season’. In the supermarket, if the lettuce isn’t on the shelf it’s because some truck didn’t show up. Disasters and frustrations are inherent in farming – producing food isn’t always easy. As we begin to find the story of our food, other things slip into place at the same time. We are attracted to the foods with shorter supply chains and we develop relationships with the people who provide it. We are willing to pay a fair price for it because we understand what went into making it. And we start to update our own reference database under this new paradigm. It’s unrealistic to think that all of our food will have a story, but we tend to appreciate it more when it does.
Final words
Whether motivated by Horsegate or some other food scandal, governments around the world seem to be moving food fraud further up the priority list. This is reassuring, but we must also be realistic. Governments aren’t likely to show great concern over a little unlabelled added water in our ham when three-quarters of supermarket chickens are contaminated with campylobacter or when people are dying from an E. coli O157:H7 outbreak. But, having fallen victim to some tasteless (pun intended) practical jokes, governments are looking at how to avoid being so gullible next time and reducing vulnerabilities in the food supply. As some food fraud scandals have shown us, there can be serious health consequences to some types of fraud. These have been acute cases; we have yet to learn what chronic implications there may be.
As food authenticity becomes a greater factor in consumer choice, the food industry will also be further motivated to audit its processes and reduce its exposure to food fraud. As consumers, our role is to hold the industry accountable.
We must be prepared, however, for food fraud to become more prevalent before it gets better. Climate change combined with rising demand creates an ideal environment for fraud. Intelligence gathering, such as is being done by the NCFPD (described in Chapter 1), will help identify where in the food fraud haystack analysts should be looking: for example, flagging Spanish olive oil after a particularly poor yield of olives in Spain. Intelligence and technologies that enable food enforcement agencies and analysts to be proactive certainly won’t put an end to food fraud, but they might keep them one step ahead in the scientific arms race against the fraudsters.
One of our greatest realisations in the process of writing this book is that food fraud is a continuum on many levels. There are actions that are clearly illegal (fake milk) and actions that are legal with an air of dishonesty (some fruit preservation methods). Food scandals range from harmless (billionaires battling over rare wine) to deadly (methyl alcohol in cheaper wine), and from financially insignificant (pennies-worth of added water) to market-crashing big business (the Soybean or Salad Oil Scandal of the 1960s). Even the mindset of the criminals who carry out fraud lies on a continuum from immoral criminal to creative problem-solver. Between these extremes lies everything in between. This world of food production, let alone food fraud, is far from black and white.
In order to be clearer on what constitutes food fraud we first need to resolve some of these rather grey areas that lie within the legal framework of food production. How are we being misled about our food with behind-the-scenes processing methods, blurring the lines of reality? How much of our food is being manufactured to pass certain tests? For example, if food is manufactured to meet nitrogen content requirements with no regard to the source of that nitrogen, is this not misleading in terms of its nutritive properties? Throw into this mix technologies that are developing faster than we can understand them, such as the use of nanoparticles, and we have an interesting future ahead of us.
We live within a complex food culture, it’s true. But we are not powerless within it by any means. Just as we take action to minimise risk in other aspects of our lives – looking before we cross the street or protecting ourselves against sun exposure – we can be active in our food choices. As we have learned, many of the food forensic analyses are based on the concept of ‘we are what we eat’. Humans are no different. The chemicals from our food become part of us and we should not be passive about what we are putting into our bodies. It is fundamental to our well-being. Our food system is such that many things lie outside our control, but there are always choices. We are, after all, the consumers, and only we decide what to put in our mouths. Choose well.