Source: The Conversation – UK
Battenberg cake is one of my favourite cakes. But when I tell people that one of the things I like most about this cake is its E-number, they tend to look at me strangely.
It contains the raising agent E541, acidic sodium aluminium phosphate, which is one of the most restricted food additives in the UK. This is due to health concerns about human exposure to aluminium.
According to the UK government regulations, E541 is permitted in almost nothing except “sponge cakes produced from contrasting coloured segments held together by jam or spreading jelly and encased by a flavoured sugar paste”.
The reason for this curious exception is that Battenberg manufacturers managed to persuade the authorities that the additive was essential for achieving the cake’s chequered pattern, and that aluminium exposure from such a niche product wasn’t a health risk.
This level of specificity in the regulations surprises most people, who assume that additives are loosely regulated, casually thrown into food by manufacturers cutting corners. It’s part of a massive counter-movement against additives, driven by fears over ultra-processed foods and a desire for “clean” labels. Though these concerns are understandable, my view of the scientific evidence is that the reality is a little different.
Additives, of course, are compounds used to enhance foods in different ways, but mainly they are about control. When you cook in your home kitchen, the results can be very variable – which is often part of the fun. No-one expects two homemade cakes to look or taste the same, while breads out of your kitchen oven can be very different if you make them from different batches of flour.
For commercial foods, it’s a different story: industrial production relies on predictability, while consumers expect consistency. Few of us would be happy if supermarket breads, biscuits or burgers varied from batch to batch. So commercial foods are usually standardised — and additives help to achieve that.
Welcome to our series exploring the cutting edge of food science. From the latest advances in meat alternatives to weird and wonderful new additives, science is transforming what we eat like never before. This series will bring you up to speed on all the latest and give you plenty of, er, food for thought.
Their number one role is preservation: extending shelf life, making it possible to produce foods further away, and often making them more affordable in the process.
Propionic acid (E280) stops bread from going stale and mouldy. Antioxidants like vitamin C (E300, aka ascorbic acid) and vitamin E (E306/tocopherol) prevent fats from oxidising and going rancid. Emulsifiers stabilise products such as mayonnaise which would otherwise quickly separate.
Creating a specific texture and flavour is also very important. Thickeners improve the creaminess of yoghurts and some cheeses. Emulsifiers also help to make ice-cream smooth and chocolate soft. Citric acid (E330) can help zing up a salad dressing, while also dialling down the earthiness in some plant-based milks.
Another use of additives is to overcome the problem of raw products of different quality. Wheat from a wet, cold year can behave very differently from the same variety in a dry, hot year. This can mean differences in protein content and gluten formation during baking, which can affect how much breads rise, for instance.
Ascorbic acid and synthetic fats (mono and diglycerides of fatty acids (E471) can compensate for this and ensure the quality of bread is consistent. Likewise, adding E500 (bicarbonate of soda) and E336 (cream of tartar) – in other words, baking powder – ensures cakes and muffins are light and fluffy.
Kitti Charoenchai
In the same way, jam depends on the pectin content of fruits, which is affected by factors that can’t be controlled – extra sunlight during growing reduces it, for instance. So manufacturers add pectin (E440) during jam-making to ensure it gels properly.
Or take meat, whose water retention can be improved by adding phosphates like E451. This ensures that natural fluids don’t leak out in the supermarket chiller section (phosphates are also more dubiously used by some meat producers to enable them to add water to cheaper cuts so that they look more attractive to consumers). As for milk products, you can avoid the risk of separation by adding carrageenan (E407), a seaweed gum, which strengthens their protein network.
Indeed, whole product categories would barely exist without certain additives. Many low-fat spreads rely on gelling agents to mimic the texture of butter. Without sweeteners, there would be a much smaller selection of low calorie and low sugar foods.
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Very little of this is about deceiving consumers — and it should not be. The need to ensure the consistent quality of produce using additives is probably much greater than most people realise.
The remarkably long history of additives
While we’ve only referred to them as additives for about a century, these compounds have been around a great deal longer. Findings from the Qesem Cave in Israel suggest ash was being used to preserve foods as much as 200,000 years ago.
In times when the food supply has been unreliable, meaning most of our history, preserving food was essential to human survival. Entire empires have been built on the trade of another vital preservative, salt, to be used either as brine for pickling or as crystals/powder for drying.
Julia’s Graphicland
Nitrates (E251) and nitrites (E250) have also been used as additives for many hundreds of years. In Roman times they were used as a constituent of rock salt, both for preserving meat and to keep it nice and pink. With a little more chemical know-how, these compounds are still used today.
Another preservative in use since Roman times is sulphur dioxide (E220), both for wine and foods such as fruits. The Romans obtained it by mining brimstone and heating it into a liquid that could be made into sulphur candles. These could then be burned to produce sulphur dioxide gas in the presence of whatever was being preserved.
The Romans also used additives to make dull, bland food more palatable. Garum — the ubiquitous Roman fish sauce – provided salty and umami flavours by fermenting fish guts. Lead acetates, obtained from boiling grape juice in leaden pots and kettles, were used as a non-calorific sweetener – in wine, for example. It wasn’t until many centuries later that it was proven that this additive was poisonous.
Towards the end of the 18th century, we developed a better understanding of how additives work thanks to advances in food chemistry. It also became possible to extract these compounds in a laboratory, such as lecithin from egg yolk to be used as an emulsifier, pectin from apples, and agar, another gelling agent, from seaweed.
A few decades later, chemists started synthesising additives, which often proved cheaper and easier than obtaining them naturally. Salt of hartshorn – also known as Baker’s ammonia (E503) – could be made by heating ammonium sulphate obtained from soot in combination with limestone (calcium carbonate).
Previously extracted from deer antlers, this was used as a raising agent and preservative for things like digestive biscuits and lebkuchen, a German gingerbread. Much like making aspirin in a laboratory instead of extracting it from willow bark, or digoxin instead of foxglove tea (for heart problems), synthetic and purified additives allowed much better control over their use.
Scientists’ better understanding of chemical and physical mechanisms in the 19th century also allowed new additives to be developed to suit the food industry and consumer demand. These included dyes like aniline purple and martius yellow, both obtained from coal tar, and new flavours like amyl acetate, a byproduct from fermenting alcohol, which gives a sense of pear or banana. These were unveiled at the Great Exhibition in London in 1851 for the first time.
Wikimedia
Other additives allowed the use of cheaper ingredients or extended shelf lives. Borax, also known as sodium borate, was harvested from lake beds starting in the late 19th century and added to sub-standard milk and butter to mask sour tastes and kill bacteria.
Additives also began to allow the development of new products that could be used as cheap alternatives, such as margarine. Though originally made from beef fat and skimmed milk in the 1870s, it became vegetarian around the turn of the century after chemists worked out how to make food oils solidify by forcing hydrogen into them at high temperatures (known as hydrogenation).
Margarine solved one problem – the affordability of butter – but food scientists realised a few years later that it created another: it lacks the vitamins naturally found in dairy. So from the 1920s onwards, manufacturers also started fortifying it with vitamins, as well as making it more attractive by incorporating emulsifiers, flavours and colours.
Elsewhere, the use of additives has put consumers at risk, often due to unscrupulous characters. They made bread whiter with chalk, for instance, at a time when many people were already suffering from malnutrition. They sweetened wine with lead salt long after it was known to be toxic. There have even been cases in more recent times of wine being sweetened with anti-freeze.
One other notorious case was the Bradford sweets poisoning of 1858. At the time, sugar was very expensive due to high taxes, so confectionery manufacturers would mix it with plaster of Paris to keep costs down. In the Bradford case, an apprentice muddled up plaster of Paris and arsenic, which led to around 20 people being killed from eating toxic peppermint lozenges.
The modern era
The 20th century brought massive changes to the food system: a rapidly growing population needed to be fed, scientific advances provided a better understanding of food processing, and the rise of synthetic chemistry made hundreds of new compounds available. The upheaval of two world wars accelerated these processes as new products such as canned meats, sliced cheeses and even packets of crisps were all made possible by additives.
The same goes for British sliced bread. The Chorleywood process, named after the village near London where it was invented in 1961, revolutionised production of the daily loaf. By adding lard, ascorbic acid and extra yeast to dough, then mixing it at high speeds, there was no more need to wait hours for the mixture to rise.
This allowed the mass production of bread, which was extremely helpful in meeting ever growing demand. It also allowed the use of British-grown flour, which often has a lower protein content, meaning its dough traditionally didn’t rise as well. In subsequent years, other additives have also become common ingredients in this mass-produced bread, including E471 (mono- and diglycerides of fatty acids) as emulsifiers to improve dough handling and E282 (calcium propionate) as a preservative to enhance shelf life.
Wikimedia, CC BY-SA
The post-war decades saw dramatic societal changes: rising incomes, longer working hours, and more women entering the workforce. These all created demand for foods that saved time and preparation. Ready meals, packet soups, instant desserts and salad dressings all reached supermarket shelves for the first time. This wouldn’t have been possible without emulsifiers, stabilisers, gelling agents and preservatives – even if such details were quietly hidden on labels that often sought to make these products look as traditional as possible.
At the same time, synthetic coal-tar dyes made sweets vivid and soft drinks luminous. Artificial flavours like strawberry, banana, pineapple, sometimes not tasting remotely natural, could be added to almost anything at negligible cost. And artificial sweeteners made it possible to indulge without sin … or at least calories.
For several decades between the 1950s and 1970s, all these new products were seen as unambiguous progress. At a time when science was enabling everything from tower blocks to rocket ships to the pill, it made perfect sense that it was doing the same for our eating habits.
The backlash
The enthusiasm for this modern food was short lived. In 1973, Californian allergist Benjamin Feingold suggested that additives – in particular artificial dyes and flavourings – were responsible for hyperactivity in children. His book, Why Your Child is Hyperactive, became a bestseller. The so-called Feingold diet became popular among parents, eliminating artificial colours, flavours and other additives.
CC BY-SA
In Britain, Maurice Hanssen’s E for Additives (1984) was another major blow to this industry when it became a bestseller in the 1980s. It detailed the purpose and health risks of all the E-numbers, which were devised as a European mark of safety, so that only additives considered safe were allocated one. Now they became culturally inverted into a warning sign.
The case against additives wasn’t quite what many began to believe, however. There was little proof that Feingold’s diet could reduce hyperactivity, even after extensive research. This may have been because of the strong genetic component in the condition.
In 2007 the UK’s Food Standards Agency commissioned a research study to investigate the effect of some artificial food colourings on hyperactivity. Children in the study showed some increase in hyperactivity from consuming the compounds in question – tartrazine (E102), sunset yellow (E110), quinoline yellow (E104), carmoisine (E122), ponceau 4R (E124) and allura red (E129).
Yet the European Food Safety Authority decided there was sufficient uncertainty that there was no need to change the permitted use of these additives. Instead European lawmakers mandated that foods containing them carry the warning “may have an adverse effect on activity and attention in children”, which applies today in the UK and across the continent.
In parallel, the additives industry has tried to adapt to consumers’ concerns about the things that go into foods. For the past several decades, we have seen a plethora of products which claim to be free from “artificial colours and flavours” – and sometimes even “free from chemicals” (although that is impossible).
Much of this “clean-label” movement has been about replacing E-numbers with ingredients that sound more natural, though in many cases the manufacturers just replace additives with plant extracts that contain the same compounds.
Hryshchysen Serhii
Acerola extract contains vitamin C, for instance, but sounds better than E300. Seaweed extract sounds much more natural than E407 (carrageenan) and turmeric extract better than E100 (curcumin). Similarly, vegetable salts or celery extract in processed meat replace nitrite (E250). The nitrite in these compounds will still act — turning the meat more pink and killing bacteria – but the consumer is not always aware that this additive is even present.
In the EU and UK, whether something counts as an additive legally depends on what it does, not where it comes from. However, this often depends on interpretation. Acerola cherry extract, for example, is almost always added for its vitamin C content, which acts as an antioxidant. However, it usually appears on the label as a fruit ingredient rather than as ascorbic acid (E300). Clean labelling probably employs as many lawyers as food scientists.
One example of how this plays out is Naked Bacon, made by Northern Irish company Finnebrogue. The goal was to remove nitrite from bacon to make it healthier – not just create a nicer label. As an alternative to nitrite and nitrate, they used a proprietary fruit and spice extract called Natpre made by Spanish manufacturer Prosur. This was initially marketed as free from E-numbers. The Food Standards Agency, however, took the view that the ascorbic acid (vitamin C) in the mix was an additive that had to be declared. After a lengthy dispute the company agreed in 2018 to list “antioxidant: ascorbic acid” on the label. The remainder of the extract is still declared as “natural flavouring”.
As well as these kinds of uncertainties, there’s also a potential problem with plant extracts as alternatives to existing additives: a rigorously tested compound is being replaced by something less understood, and still potentially harmful, in the name of a cleaner label. They can contain natural toxins, for instance, while the levels of the additive can vary by batch.
The case for additives
Another part of the stigma against additives is that they enable industrially produced food, which has come to be seen by many as inherently unhealthy. This was abetted by the likes of US journalist Michael Pollan’s bestseller, In Defense of Food (2008), the documentary Food Inc (2008) and TV chefs like Jamie Oliver.
This mindset probably partly derives from all those unsavoury practices I mentioned in the early food industry, where chemicals were used to disguise spoilage, extend products or improve appearance.
Wrapped up in this is a romanticism of natural food, viewing chemical intervention with suspicion. Many people still see natural as better and healthier, though there is actually little evidence for this claim.
Whether industrially produced food is unhealthy depends very much on what is in the food. Foods high in fat, salt and sugar increase the risk of chronic disease, whether it is a home-baked cake or an industrially manufactured cookie. Sure enough, a recent study found no difference in health outcomes between processed and non-processed foods that meet current dietary guidelines.
With today’s focus on ultra-processed foods, it is true that certain industrial additives like emulsifiers and artificial colours and flavours are sometimes used as evidence that a product falls into this category. But the health impact of these foods is more tied to issues like high calorie-density and low fibre content than the toxicity of individual ingredients, so the additives are rarely the primary culprits.
It’s also worth emphasising that without additives, natural food can spoil much more quickly. Almost 20% of foods are lost to spoilage in retail, and more than 30 million years of healthy lives are lost every year to food-borne diseases. Without additives, this situation would be much worse. And at a time when the cost of living is such a burden for so many people, it’s hard to deny that additives make food much more affordable.
Regulatory issues
Unlike with pharmaceuticals, there is no formal system for checking whether additives are causing harm after they start being used in food manufacturing. Regulators rely on the scientific literature to keep them up to date on any risks, as well as commissioning research studies if there are reasons for concern.
The situation isn’t helped by the different classification frameworks that exist. A recent example is aspartame. In 2023 the International Agency for Research on Cancer (IARC) classified this sweetener as possibly carcinogenic to humans, causing a huge amount of concern.
Yet at the same time Jecfa, the Joint FAO/WHO Expert Committee on Food Additives, whose pronouncements influence food regulation around the world, reaffirmed aspartame’s accepted daily intake of 40mg per kg of body weight. It concluded that there was no convincing evidence of adverse effects at current consumption levels.
Luisa P Oswalt
This sounds contradictory, but actually the IARC and Jecfa ask very different questions. The IARC asks about hazard: could this substance possibly cause cancer? Jecfa asks about risk: could this substance possibly cause cancer at the amount people eat? Both can be right. A substance can probably cause cancer, only not at the amounts people generally consume.
The IARC, for instance, classes the Sun as a group 1 carcinogen, meaning it’s known to cause cancer in humans. Yet we still recommend sun exposure so that our bodies produce vitamin D. We manage the risk by reducing exposure — either by looking for shade or using sunscreen. As for aspartame, it’s worth noting that the IARC classification put it in the same category as aloe vera and pickled vegetables.
Emulsifiers are another additive currently receiving a lot of attention. Some studies have shown that they can alter the human gut microbiome and disrupt the intestinal barrier. Whether this causes harm is obviously an important question, but there’s much that isn’t yet clear: we don’t know if these effects are harmful, or whether they’re transient or lasting.
The trouble is that changes in the gut microbiome are difficult to interpret. It can change in response to all sorts of alterations to someone’s diet, and while there is some good data on links between the microbiome and health, we do not yet have a clear framework for interpreting what specific changes mean.
To be clear, change in itself isn’t a negative: fermented foods and prebiotics are recommended especially for their ability to change the gut microbiome. Regulators in the UK and elsewhere are actively investigating how to incorporate microbiome data into safety assessments, but the science is not yet at a stage where firm conclusions can be drawn.
It might still seem appealing to ban emulsifiers in the meantime as a precaution, but that might have consequences that eclipse the intended benefits. For example they could be replaced by natural lecithins from sources like egg yolks and sunflower seeds, but these are much more expensive. The consumer would bear the brunt – and there is no evidence that these alternatives are better.
There is also a question of consumer choice. Provided a food is safe to consume within established guidelines, there is a strong argument that individuals should be free to make their own choices, rather than having them imposed on the basis of uncertain evidence.
Alcohol, for instance, is another product categorised by the IARC as a group 1 carcinogen, and there is overwhelming evidence that drinking it can harm your health in numerous other ways. Yet while there are regular calls for tighter regulation of additives with a much better risk profile, calls for a ban on champagne or claret are much rarer.
This isn’t to say that the need for proportionality should always justify inaction. Regulatory agencies should and do act to protect consumers when the evidence warrants it. In 2007 data emerged that red 2G (E128), used as a colouring in sausages and burgers, was potentially carcinogenic and toxic to people’s genes. This was rightly considered serious enough that it was swiftly withdrawn in Europe and elsewhere.
The future of additives
One current area of rapid development has been plant-based foods, where achieving the texture, appearance and mouthfeel of meat and dairy requires a specific set of additives. For example, to produce plant-free dairy products that melt and taste like the real thing, food scientists add synthetic wheys and caseins made using a technique called precision fermentation. This involves inserting synthetic copies of dairy DNA into yeasts or fungi.
The first large-scale application of precision fermentation was actually in medicine in the early 1980s, producing insulin using genetically modified E. coli. The food industry got onboard in the early 1990s, with chymosin, an enzyme essential for cheesemaking to separate the curds and whey. It became the first major precision-fermentation product, and is now used in many milk-based cheeses instead of traditional rennet from calves’ stomachs, producing more consistent results and also vegetarian products into the bargain.
In the last couple of years, companies are now offering the entire suite of dairy proteins including whey, casein and lactoglobulins made in a fermentor as opposed to a cow. This is enabling products that are bio-identical to dairy rather than just plant-based alternatives, such as Bored Cow milk in the US. The line between additives and food itself is also increasingly blurring as different companies and research groups compete not just to produce individual proteins but entire muscle tissue in fermentation tanks.
The Image Party
Meanwhile, AI is somewhat inevitably being leveraged to help drive additives forward. One promising line of enquiry is discovering compounds that can fool human receptors into thinking they’re consuming salt or sugar that isn’t really there, or mask other tastes such as bitterness.
Also promising is a technique called nano-encapsulation, which raises the prospect of wrapping additives in microscopic biopolymers or bubbles of lipid (fat) to prevent them from spoiling. This could prevent colours from fading on supermarket shelves, or vitamins from being damaged by heat, for instance.
Whatever you think of these developments, food additives will probably be around for as long as humans need to consume food that is not freshly prepared. They are neither inherently good nor inherently bad, just tools that can be used to make food safer, more affordable and longer lasting.
Next time you enjoy a slice of Battenberg cake, indulge me by sparing a thought for E541 — and for the system that decided exactly where it could be eaten.
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Gunter Kuhnle has received research funding from Mars, Inc., a company engaged in flavanol research and flavanol-related commercial activities. As a previous member of the EFSA ANS panel and the Committee on Toxicity (FSA), he was involved in the evaluation of food additives. He is currently a member of ACNFP. Gunter also had discussions with Finnebrogue ahead of the release of their Naked Bacon product. He has no financial interest in either Finnebrogue or Mars. The views expressed are his own.
Original source: https://analysis1.mil-osi.com/2026/09/18/the-long-fascinating-history-of-food-additives-and-why-were-stuck-with-them/