The lemonade bottle had been squatting at the bottom of my fridge, supposedly on hand for an emergency Pimm’s. It shivered there for about four months, only a quarter of it drunk, before I decided to tip the contents down the sink (I prefer emergency Bellinis). That’s when I noticed the sell-by date: June 2008.

Without sodium benzoate, otherwise known as E211, my lemonade would have gone off more quickly, perhaps a couple of weeks after I purchased it in early 2007. In fact, I may not have been able to buy it at all.

“If we got rid of preservatives, we might not have the same range of products on the supermarket shelf,” says Christine Welberry, from the Food and Drink Federation, which represents manufacturers. “It might not be viable to manufacture a product and put it in the shops if it has only a few days before it goes off.

“Shelf life is a consumer convenience, as well as being part and parcel of the food chain. The consumer wants the product in her store cupboard for long enough to be useful to her. And all manufacturers make products based on consumer demand, so people obviously want to buy these products.”

Thanks to researchshowing that combinations of artificial additives can induce hyperactivity in young children, shoppers are being encouraged to contemplate a future without food additives. Such a future could lead to frozen and canned food becoming fashionable again, and to the disappearance of some products from supermarket shelves altogether. Consumers keen to shun additives in favour of chilled, fresh foods would also be wise to install fridges in their car boots, according to one food expert.

Professor Jim Stevenson from Southampton University tested, on young children, cocktails of additives that included the following artificial colours: E102 (tartrazine), E104 (quinoline yellow), E110 (sunset yellow), E122 (carmoisine, sometimes called azorubine), E124 (ponceau 4R) and E129 (allura red). The cocktails also included the preservative E211 (sodium benzoate). The research, funded by the Food Standards Agency (FSA) and published in TheLancet, showed that children fed a typical intake of these additives were less attentive than children placed on additive-free diets. As a result, the FSA recommended that parents with hyperactive children steer clear of the additives used in the Southampton study.

Many organisations, including the Soil Association, which champions organic farming and food, and the Hyperactive Children’s Support Group, insist that the FSA should have gone further by demanding that manufacturers drop the tested additives immediately and advise all parents, whether their children are hyperactive or not, to avoid them.

Even the Soil Association (SA), despite its purist approach to food, believes it is unnecessary and impractical to ban all additives. It currently permits 32 – among a total of about 300 additives permitted in food under European regulations – to be used in organic food. The key difference is that the SA emphasises the use of natural additives (such as salt, and colourings derived from plants) rather than synthetic additives.

Parents echo this concern about man-made chemicals in their children’s food, with most preferring that artificial additives are either removed or replaced with natural alternatives. Marks & Spencer, for example, has removed all artificial colourings and flavourings from 99 per cent of products and has introduced gourmet jelly beans coloured naturally with beetroot, plum, pear and pineapple juices or banana, peach and raspberry fruit purées.

There are minor casualties of the modern aversion to artificial additives. Some still mourn the blue Smartie: it disappeared when Nestlé dropped Brilliant Blue (E133) from its palette and failed to find a natural alternative. Blue Smarties, however, may not be the only product to disappear from children’s menus. Tinned processed peas are a challenge because the manufacturing process turns them grey. Frankfurters and processed sausages undergo a similar leaching; their natural pink is restored artificially. If the colourings were dropped, would shoppers still buy grey peas or beige frankfurters?

No, according to Claire Nuttall, brand consultant at Dragon Brands, which advises supermarkets and manufacturers on consumer issues. “Ninety per cent of what you eat is with your eyes, and even if you agreed with the principle of no additives, you would struggle to get your head round actually eating grey peas. But the general trend is that consumers want additives out of their food.”

Losing colourings, especially if there are natural replacements, is no big deal. Losing preservatives is a bigger challenge. Sodium benzoate (E211), which featured in the Southampton study, is added to carbonated drinks and some jams, among other things, to stop bacteria and fungi growing. Welberry, from the Food and Drink Federation, said there would be public health implications of curtailing its use. There would also be logistical problems, as drinks would need to be refrigerated before delivery. Consumers would need to shop more frequently if preservatives were not used; in addition, it would not be viable to make some products, which would disappear altogether.

Nuttall also predicts that the loss of preservatives, as opposed to colourings, would make life difficult for the consumer. “Our research has found that consumers really value convenience, and are loath to give it up. It is also likely to affect low-income shoppers adversely, because products with longer shelf-lives tend to be cheaper.

“But we could educate shoppers into buying short shelf-life products and freezing them. You could stimulate a wholescale reappraisal of the frozen category, which has always suffered an image problem. In fact, you could imagine manufacturers urging consumers to “buy frozen – it’s additive-free”. Birds Eye is one manufacturer that has gone down this route rather successfully.”

The Institute of Food Research in Norwich is running a project to investigate the use of extremely high air pressures – 10,000 times atmospheric pressure – to kill microorganisms. The technique, which lessens or removes the need for preservatives, is already used to preserve oysters and seafood. The EU-funded project will investigate whether other food groups, especially vegetables, can be protected in this way.

According to Tony Hines, a spokesman for Leatherhead Food International, a food research company that works with supermarkets and food companies, the move to additive-free foods is pushing us towards chilled cabinets rather than a larder full of tins. But there is a mismatch: although we want to eat fresh food, we still only want to do one weekly shop.

“In terms of consumer attitudes towards food, people tend to see chilled products as the healthy options, rather than canned or frozen foods, so that’s the real growth area at the moment,” Hines says. “The problem is that we lead increasingly busy lives, so we expect our food to stay fresh for a long time. Since most of us shop only once a week, what we buy on a Friday is expected to stay fresh until the following Friday. Often, this is not possible with chilled food.

“We as consumers often play a part ourselves in reducing the shelf-life of chilled goods by putting them in boiling hot car boots after we go shopping, so it might be that we need to develop things like fridges and freezers in cars. Even little things like taking a cool box to the supermarket would make a tremendous difference on a hot day.

“We need to encourage a combination of little changes in lifestyle choices and finding alternative technologies.”

Additional reporting: Ed Hancox