Swallow This: Serving Up the Food Industry’s Darkest Secrets

To backtrack here, Vesta, the pioneering ready meal brand, was already pushing a sales pitch that was to become all too familiar to British consumers. Its ‘lavish’ chicken curry came ‘complete with an authentic curry sauce’. It was ‘ready prepared by Vesta for you to cook’ by ‘expert chefs who have done the hard work for you’. OK, it was a slowcoach of a product by today’s ping-of-a-microwave standards, taking 20 minutes to reheat, but that seductive labour-saving promise, combined with prominent claims of authenticity and the skill of a professional chef, is still the central plank in processed food marketing today. The ready meals entrepreneur, Sir Gulam Noon, summed up the industry’s vision of itself when he told the Financial Times that he ‘changed the palate of the nation, and broke the housewife’s shackles from the kitchen’.

These days, convenience foods have certainly moved on from the Vesta days, both in terms of their technical sophistication and the claims advanced for their ‘realness’. In the ready meal category, lasagne and chicken tikka are now the two best sellers. But I have yet to encounter a ready meal that tastes a lot, or even a little, like homemade food. They have improved from the Vesta days, but freed from their packaging and reheated, they generally remind me of the dispiriting hot meals dished up by budget airlines. That sticky brownness, that larger-than-life tinned tomato soup aroma, those uniform textures and consistencies, those starch-stiff ecru sauces, the predictable high tone twinning of sweet with salty, and the consequent thirst that surely follows; for me, ready meals are a sorry apology for real food.

I am forced to revisit this prejudice at regular intervals, however, when newspapers ask me to investigate a particular convenience food category – value, low-calorie, children’s, free-from, for instance – and the claims made on their packaging. And trust me, there are legions of products to investigate. Looking at the chilled category alone, by 2013, UK-based food companies were manufacturing over 12,000 different chilled food recipes. This is a big business – over £10 billion a year – which represents some 13% of the UK’s total retail food market. Within this grand total, ready meals are by far the largest sales category. The UK ate its way through 3 billion of them in 2012.

The only way to investigate ready meals properly is to buy a batch of comparable products from a variety of different retailers, and take them home to study in depth; it’s not something that you can do easily in the supermarket aisle. The ingredients listing is obviously the first port of call, and these days, because processed foods such as ready meals are often complex, multi-ingredient products, these lists can run to several paragraphs of tiny print that’s more or less impossible to read without some sort of magnification; unless, that is, you happen to have 20/20 vision.

Editors often want a description of how each product looks and tastes, so I remove them from their packaging and reheat them in the oven or pot. Now, perhaps if you eat them regularly, the sight and smell of warm, bubbling convenience meals will set your gastric juices flowing, but for people like me who aren’t, they are strikingly different from the home-prepared equivalent. For starters, they often have a quite powerful odour, one that tends to hang around in the bin, sink and dishwasher long after the contents are gone.

Of course all food, including home-prepared food, makes itself known to the nasal passages to a greater or lesser extent, but usually in a pleasant, appealing way. Yet when you compare a selection of processed foods, you start noticing that they have particularly distinctive smells, or rather, a curiously similar portfolio of smells.

Now, according to Greencore, one of the largest chilled food manufacturers, the UK chilled food industry is ‘the most advanced in the world because of its high standards, rigorous safety and management systems and the sheer quantity of exciting new recipes which it develops constantly’. That would make you think that there is a rich diversity amongst all the convenience foods on our shelves. But when I opened them in my kitchen, I found that I could easily classify my ready meals into odiferous families, a bit like houses of cards: aces, spades and so on. First there’s the ‘red’ family, that’s the hot tomato/pizza/lasagne/tomato and basil soup/‘med’ veg bunch. Next up, there’s the ‘brown’ family, think of cottage pie/steak and kidney/casserole/stew/Peking duck, chow mein noodles and everything sold with a barbecue label. In the ‘beige’ family, variously labelled breadcrumbed/battered products share a strong resemblance, a particularly haunting, almost acrid oily aroma that soon impregnates the oven and lingers thereafter, irrespective of whether they are fish, meat or vegetable-based. The all-out attention-grabbers are the Indian-themed dishes, whose spices give them just enough personality to distinguish them from the others, although they otherwise share many similar characteristics.

When it comes to tasting ready meals, the flavour profiles are every bit as monotone as the smells. Tasted blind and mashed up to disguise any tell-tale texture, one might easily mix up a sausage casserole with barbecue spare ribs, or confuse Mexican chicken fajitas with sweet and sour chicken. Why is this?

It all began to fall into place when I was in the test kitchen of a ready meals factory, where food technologists check the taste and ‘visuals’ (appearance) of the day’s output to ensure that they conform to a tight specification. ‘The objective’, one executive explained. ‘is to see that the consumer gets the same taste experience every time’. Now this explained a lot. When you stop to think about it, home-cooked food varies all the time. For a kick-off, it reflects the cook’s mood. Anyone who cooks can testify to how an oft-made recipe can turn out differently, depending on your mental state; harassed and rushed perhaps, serene and calm maybe, or even distracted and not fully engaged. Patiently caramelised onions one day can be burnt threads the next. There’s a fine line between a custard sauce that obligingly coats the back of the spoon, and a bowlful of curdled egg.

The ingredients for home cooking also vary in subtle but palpable ways. One brand of tinned tomatoes doesn’t give quite the same result as another. Lemons yield variable amounts of juice. Some bunches of herbs can be more aromatic than others, some spices fresher. Seasons make their presence felt too. Fresh summer garlic is sweet and subtle; the same bulb, stale, overwintered and used in March, can have a blunderbuss effect on a dish. Stewing beef bought from the supermarket, and encased in plastic with gases to keep it looking ruby red, will cook differently from the same cut, simply wrapped in waxed and brown paper, purchased from an independent butcher.

You may be a huge fan of your mum’s homemade steak pie but have to admit that, this week, it didn’t taste quite as great as usual. Or the opposite might be the case. One night, for no apparent reason, a familiar stir-fry suddenly seems to have acquired a mystery X factor. Was it that the peppers were less watery? Was the oil hotter because of that phone call? Was it down to the noticeable freshness and lack of fibre in that particularly good-looking root ginger?

It’s the intrinsic variation that makes home-cooked food eternally interesting, but variation is the sworn enemy in industrial food processing. Indeed, all the systems put in place by manufacturers of ready meals and other convenience food lines are geared to eliminating it. The whole purpose of the endeavour is to iron out every possible high and low, and produce a totally standard product that always looks and tastes identical, 365 days of the year. As one government food safety manual puts it: ‘To achieve a consistent product with the same appearance, flavour, shelf life, etc., it is important that the ingredient quantities, quality and the processing steps are always the same’.

The lengthy process of achieving this begins with the food manufacturer’s shopping list. The aim here is to have maximum control over ingredients, to ensure that they are always identical. On an industrial scale, this means buying in ingredients to a very tight specification from specialised companies. Surprising though it might sound to the home cook for whom ingredient preparation is probably the largest component of the cooking effort, food manufacturers carry out little or no preparation of raw ingredients. Instead they buy them in substantially pre-prepared. So, contrary to the notion that ready meals and other convenience foods are brought to you by a company that does all the hard work, it would be more accurate to say that they come from a company that ‘cooks’ products made with a list (often long) of ingredients and sundry additives that have already undergone some form of preparation by several other companies. In other words, the company that appears to be saving you work (usually a supermarket), is devolving that work to another company (a food manufacturer), which in turn gets other companies (food processors) to do the prep for it. These processors, in turn, may be quite remote from the primary food producers: farmers and growers.

The convenience food chain that supplies the consumer is made up of many links, links that often cross continents. In food manufacturing logic, this elongated chain is not at all crazy, quite the opposite. After all, the basis of any automated industrial manufacturing, be it cars or chicken tikka, is breaking down all the necessary production stages into component parts that can be carried out by separate teams on the assembly line.

The Chilled Food Association presents its industry’s products as ‘local’ because ‘virtually all chilled prepared foods are made in the UK’, but the ingredients used to make the finished products are often anything but. It quotes one development chef as saying: ‘Food should be simple, well cooked and flavoursome, with minimal amount of handling. It is also essential to use the best available ingredients to hand and promote local produce wherever possible.’ A statement somewhat at odds with industry recruitment literature, which describes ‘sourcing fresh ingredients globally from carefully chosen suppliers’ as a key part of the job.

In fact, the food manufacturer’s shopping list is thoroughly international. When an ITV Tonight investigation, Food Facts and Fiction, commissioned a UK food technologist with extensive experience of food manufacturing to make a very traditional British-sounding lamb hotpot ready meal of the type commonly sold by supermarkets, he came up with a product made from 16 ingredients, sourced from ten different countries, including New Zealand lamb, Israeli carrots, Argentinian beef bones and Majorcan potatoes.

Irrespective of which country they are buying from, if food manufacturers can buy an ingredient in frozen form, they will. That may seem surprising, even counterintuitive, given that they often go on to sell them chilled as ‘fresh’, but freezing is seen by food processors, quite correctly, as the safest way of storing ingredients to protect them against any food poisoning risk. Frozen ingredients are also easy for industrial food manufacturers to handle. They don’t arrive at the delivery bay with a stopwatch ticking, needing to be cooked promptly. Instead they can be, and are, stored for months, even years, and brought out as and when they are needed. So most of the meat, fish and vegetables arrive at the factory gate in a frozen state, already months, possibly years, old.

By buying in frozen food, manufacturers liberate their purchasing from the vagaries of the seasons and price fluctuations, and benefit from buying ingredients in frozen bulk on a global market. So, unless the label specifies otherwise, it’s highly probable, for instance, that the chicken in your ready meal was purchased frozen from either Thailand or Brazil. Around 40 per cent of the chicken we eat in the UK is imported, almost all of it destined for food processing or catering. If required, large chicken exporters in these countries will also obligingly supply that frozen chicken pre-cooked, and/or ‘marinated’: injected with water, cornflour, salt, and even other flavourings. Few consumers notice the tell-tale label description (‘cooked marinated chicken breast’) not unreasonably assuming that when a product contains chicken, that means 100 per cent chicken, probably British, the sort you’d cook at home, with nothing else added.

It’s an eye-opener to see the ingredient storage zones of food factories. In a typical operation, almost all the meat, be it chicken, lamb, pork or beef, is bought in frozen. So before it can be used it has to be defrosted for five to six minutes. Don’t for a second imagine that in big food manufacturing plants there are lines of people patiently peeling mounds of carrots and potatoes. In your typical industrial-scale factory, 80–90 per cent of all fresh vegetables are purchased in frozen form.

As anyone who cooks from scratch knows, many savoury recipes begin with chopping onions and finely mincing garlic, but food manufacturers do away with all that fuss. Instead they typically use pre-peeled frozen onions. These are purchased, usually from Poland (which seems to have captured the EU market in onion peeling) and despatched to another factory to be defrosted, chopped into 10 millimetre dice, or sliced, frozen once more, then re-supplied ready for use, wrapped in a plastic sleeve inside cardboard boxes. You’ll never see a bulb or clove of garlic in a food manufacturing factory either, as it is commonly sourced (sometimes from Europe, usually from China) pre-chopped and frozen, or in a processed purée form.

Potatoes – now there’s another labour-intensive vegetable – similarly arrive at the factory frozen and pre-sliced to a specified thickness, or cut into neat 20 millimetre cubes. While chefs and home cooks routinely stump up for fresh leafy herbs, appreciating the fragrance and vitality they bring to a dish, food manufacturers like a shortcut. A stroll through the food manufacturer’s ‘fridge’ will show you boxes of frozen ones, pre-chopped by some other food processor in a distant factory. And guess what, they are nothing like the fresh equivalent. So why use them? ‘Frozen herbs have a better kick, or flavour profile’, one manufacturing executive told me, but no self-respecting chef or home cook would put up with the ready-to-use herbs (from Germany) that I saw. They looked grey-green and even the coriander had none of the fragrance that this herb so reliably brings to a dish; in fact, it smelt of nothing. But food manufacturers like prepped ingredients like these because, from their point of view, buying in prepared ingredients is actually ultra-responsible because they come from factories specially geared up to handle them, where the skills needed, and the risks posed, are quite different from those in their own process.

Food manufacturers apply the same logic to cooking fruits and vegetables. Why would they bother with time-consuming, laborious preparation, after all, when they can buy them in frozen and ready to use? They only need to place an order, and pallet-loads of pre-fried or grilled aubergines, peppers and courgettes, sliced to the ideal dimensions for your roasted Mediterranean vegetable pizza, will be delivered to the loading bay. Why would they muck around setting up a factory line for the scratch preparation of fresh aromatics for your Thai curry when they can source ginger already sliced into julienne strips, lime leaves already ‘milled’ into specks, and ‘nuggets’ of pulped chilli – all frozen? In food manufacturing terms, it is economic lunacy to pay someone in the UK to remove the zest from real fruits for a cheesecake, when you can buy in frozen lemon, orange and lime zest that has been mechanically removed, in a dedicated citrus processing plant, in another country. But this remorseless logic also helps explain why the resulting pizza, curry and cheesecake retain only a faint, blurry memory of the freshly prepared equivalent. These pre-processed labour-saving ingredients are simply not fresh, and storage has robbed them of their initial sparkle.

In the food manufacturer’s ingredient store, you get a further insight into why processed convenience foods don’t taste convincingly like their home-cooked equivalent. In the same way that you will never see a stray onion skin lying around a ready meals factory, you’re extremely unlikely to see an eggshell either. Eggs are supplied to food manufacturers in many forms, but almost never in their original packaging. Instead, they come in powders, with added sugar, for instance, or as albumen-only special ‘high gel’ products for whipping. Liquid eggs will be pasteurised, yolk only, whites only, frozen or chilled, or with ‘extended shelf life’ (one month), whatever is easiest. They may be liquid, concentrated, dried, crystallised, frozen, quick frozen or coagulated. Manufacturers can also buy in handy pre-cooked, ready-shelled eggs for manufacturing products like Scotch eggs and egg mayonnaise, or eggs pre-formed into 300-gram cylinders or tubes, so that each egg slice is identical and there are no rounded ends. These hardboiled, tubular eggs are snapped up by companies that make sandwiches. Manufacturers can also take their pick from bespoke egg mixes, ready to use in everything from quiches and croissants to glossy golden pastry glazes and voluminous meringues. And there is always the cheaper option of using ‘egg replacers’ made from fractionated whey proteins (from milk). No hurry to use them up either; they have a shelf-life of 18 months.

Some ingredients used by food manufacturers are recognisable to home cooks: products such as aseptic tomato paste, a cooked tomato liquid, aren’t so different from cartons of passata you might keep at home, for example. True, they come in shuddering foil packs with the dimensions of a clothes dryer in a launderette, yet the contents aren’t dissimilar. But alongside these scaled-up items is a collection of ingredients that you won’t find in any domestic larder. Instead, you’ll find products designed for particular factory purposes. If, for instance, you needed to make a batter at home, you would most likely start with flour and eggs, but manufacturers turn to ready-to-mix batters, or ‘reliable coating systems’ as they are known in the trade, specially formulated to produce identikit results in factory-scale production; everything from ‘pre-dusts’ and ‘adhesion batters’ to fritter mixes with a ‘cake-like interface’ and ‘ovenable systems’ designed for reheating in the microwave.

Why not just mix a fresh batter from scratch? As one supplier of batters explains:

Meats, poultry, vegetables and other organic substrates can vary widely in moisture level, fat and protein content. The degree of denaturisation, surface irregularities and variations in the expansion and type of protein may also come into play. The appropriate batters can help offset the effects of processing variables such as line speed, age and brand of processing machinery, water quality, set-up time, the method of reconstitution used and the amount of breading pick-up.

Strip away the characteristically industrial language of food manufacturing here, and what this means is that whether you are talking about the batter on your haddock goujons, chicken dippers or onion rings, a pre-mix guarantees uniform results, day in, day out.

Where a home cook would use breadcrumbs, manufacturers use lots of specially devised breadcrumb-like products, a necessary component of many ready meals and other convenience foods, everything from the crunchy topping on your cauliflower cheese meal-for-one through fish fingers to chicken Kievs. Indeed, they have their pick of a whole range of breadcrumb-like coatings that come in a variety of hues (due to natural or artificial colours), with different textures (from light and crispy to hard and crunchy), and in different crumb sizes. No need ever to bother with a loaf of bread.

Rather than making potato gnocchi from freshly boiled potatoes, flour and egg, the way your Italian nonna used to do (what a hassle!), food manufacturers can just add an egg and water solution to a tub of pre-seasoned, roller-dried potato flakes, designed especially for this purpose, in a mix that already contains added emulsifiers, stabilisers, citric acid, antioxidants – all to oil the wheels of the industrial process – and carrot extract, the latter to give the beige-grey dough a more wholesome colour.

Of course, any well-stocked home cook’s kitchen has a store cupboard of ingredients that add additional flavour dimensions to food. Salt and pepper, naturally, and then things like soy sauce, spices, sesame oil, mustard and vinegar, but manufacturers can call on a number of shortcut ingredients, available only to the trade, to do the job. You will see the odd tub of ground spices in the ready meals factory, but in food processing, few ingredients are that simple. Instead there are glazes, seasoning mixes, coaters, rubs and marinades. To an optimist, these might sound quite normal, but they are far from it. They are what’s called in the business ‘flavour technology systems’ or ‘flavour delivery systems’: products specially formulated to encapsulate the aroma and taste of natural food in a handy, ready-to-use form, either dry, or in liquid form as part of a ‘liquid flavour system’.

From a food manufacturer’s perspective, why mix together several different seasonings, aromatics and condiments when you can buy one customised product that will give your basic ingredients exactly the twist you want? Barbecue glazes, for instance, come Cajun, honey roast, smoky, hot and spicy, or Deep South-style. Pre-cooked, water-injected, defrosted chicken can be ‘marinated’ or ‘rubbed’ with a whole list of them – Chinese, Moroccan, Tandoori, Thai, Mexican, Italian, Creole and more – to imbue the same bland meat with a veritable United Nations of food manufacturing personality.

While a home cook would need to marinate meat for several hours, or even overnight, with an off-the-peg marinade, manufacturers can achieve that just marinated look in minutes.

Forget the faff of grinding spices, or pulverising aromatics. Food manufacturers prefer to buy in ready-made ‘cuisine pastes’ from companies who understand ‘the total requirements of manufacturers of savoury foods, providing complete, tailored solutions for a wide range of applications’. As the marketing blurb for one such company expresses it, ‘our chef quality range of savoury ingredients deliver premium taste profiles and are dry blended to make your production process easier’.

A tub of ready-made pepper coating can be used to create an attractive crust, like that on a well-seasoned steak, or jerked chicken, as a flavouring for couscous and pasta salad, or to smarten up a flabby, defrosted salmon steak. Pass pallid poultry pieces through a machine that sprays on caramel before you cook it, and it will take on the Miami beach lifeguard bronze of a home-roast joint. A touch of liquid ham and cheese flavouring, incorporated into other liquid ingredients, will make your spaghetti carbonara smell particularly savoury. A hint of fish flavouring will reintroduce the memory of taste into the anodyne prawn in the middle of your sushi roll.

The composition of the products manufacturers use to flavour and lend personality to ready meals and other convenience foods varies but, in a nutshell, they bear only the most distant notional similarity to those traditionally available to the home cook, not least because they are often multi-ingredient items in their own right. Whatever their name and supposed ethnic identity, the master key recipe for these prêt-à-porter flavouring shortcuts doesn’t vary that much either. Whether wet or dry, it is hard to escape the same old roll call of starches, gums, sweeteners and salt, along with synthesised flavourings and colourings. In one typical supermarket Chinese-style pork rib ready meal, the glaze alone contains 17 ingredients: sugar, salt, cornflour, dried glucose syrup, tomato, garlic and beetroot powders, spices, guar gum, vegetable oil, and more.

But to food manufacturers, this custom-made shopping list makes total business sense. Why, for instance, would you shell out for butter when you can instead dose your recipe with 0.02 per cent butter extract that will, as one flavour company promises, give your products a ‘characteristic butter flavour … [that] works well with bakeries, confectionery, candies, ice cream, popcorn, cereals, dressings [and] combines well with vanilla and cocoa flavour’? Or, there is always the option of using butter powder. Described by one company that makes it as ‘a powdery, homogeneous and free-flowing cream to yellow powder’, it is manufactured by spray-drying a mixture of butter, maltodextrins (starch) and milk proteins; a real boon to manufacturers who want an up-market ‘made with butter’ promise on their product label, but who don’t want to fork out for the real thing. Butter is an expensive ingredient as far as food manufacturers are concerned. When you are churning out hundreds of tonnes of product a day, even a small reduction in the quantity you use can reduce ingredient costs significantly.

And why clog up your cold storage area with vats of real cream when you can use a ‘powdery, homogeneous and free flowing cream to yellow powder with a cream taste and smell’ that doesn’t need to be chilled, and takes up a fraction of the factory space?

To a manufacturer whose constant concern is reducing or at least containing costs in the face of regular price rises in raw materials, it seems quite logical to use, say, a powder made from freeze-dried apricots, blended with some type of starch, that smells just enough like the fresh fruit to pass muster in your Danish pastries or yogurt, rather than much more expensive fresh apricots, or frozen apricot pulp.

From water-injected poultry and powdered coagulated egg, to ultra-adhesive batters and pre-mixed marinades, the raw materials in industrial food manufacturing are rarely as simple as most of us would like to think. In fact, they commonly share quite complicated back-stories of processing and intervention that their labels don’t reveal. Indeed, they are predicated on ingredients that are processed, comprised versions of the real thing, far removed from their original forms.

The undisclosed hidden history of their ingredients helps explain why ready meals manufactured in factories cannot hold a candle to the competently homemade equivalent, prepared in a domestic or restaurant kitchen. It also sheds light on why supposedly different ready meals from different retailers taste so similar. The big supermarket chains that sell us these products share the same manufacturers. These manufacturers, in turn, share the same pool of ingredient suppliers. The specifications our multiple retailers give to manufacturers may vary marginally – one might prefer a runnier stew, the other a stickier one – but the industrial systems they are locked into leave little leeway for genuine variety. One conveyor belt, on a given day of the week, is dedicated to meals for Asda or Tesco, while another does pretty much the same thing for M&S and Sainsbury’s. One chain might specify a certain ingredient, say free-range pasteurised egg rather than the caged-hen equivalent, but no manufacturer can afford to alter their production system on request, especially when they very rarely have the security of proper contracts from retailers, only short-term agreements. So like a subscription to over-hyped satellite TV channels, the selection of ready meals on supermarket shelves, despite the apparent diversity, is surprisingly homogenous in terms of its contents.

And if the larder used by manufacturers is, shall we say, samey, what of the production method? In the context of food processing, the word cooking merits permanent parenthesis because the techniques used are so radically different from the time-honoured equivalent as understood by cooks down the ages. Any good domestic cook making the meat ragù for a pasta dish, for instance, would begin by browning onions and mince before adding the liquid ingredients, in order to deepen the flavour. In food mass production, you can forget pre-browning. All the ingredients will be measured into one gigantic, temperature-controlled industrial vat and bubbled up for a specified time until they form a stew-like mass. Add a dash of extract of this, and powder of that, and hey presto, you have the recipe for a meat layer. A dose of caramel will compensate for the missing taste, colour and aroma that natural browning would have given the dish. A little added thickener, in one form or another, usually from cheap sweet starches and sticky gums, will give the illusion of the natural viscosity found in the patiently made traditional article. All that remains is to have the mixture spewed into plastic cartons, along with the other manufactured white sauce and pasta components, and passed through blisteringly hot, cavernous steam-injected ovens to ensure that your lasagne or pasta bake remains soft for reheating. A rapid cooling in a spiral chiller, a mechanical conveyor system that moves food through a continuous chilling process, and the job is done.

What you have here is a streamlined production system of assembly, amalgamation, fusion, combination and transformation by heat that very efficiently flattens out any slight lingering personality in already anonymous, much compromised ingredients. No wonder ready meals taste so spookily similar. If the beauty industry is in the business of selling hope in a jar, the factory food industry is in the business of selling hope in a plastic carton, under a cardboard sleeve. It promises us something near-instant and edible that tastes more or less like real, home-cooked food – a promise that it is structurally unable to deliver.

2

On the factory floor (#u15b32a08-a063-52a7-8316-63680b172a5c)

I now realise that I was naïve, but there was a time when I expected food processing companies to joyously announce their existence. I suppose that I had imagined factories with household names above the door, and proud signage explaining what they do. ‘Smith & Sons: delicious meals in minutes’, that sort of thing. I can’t think why I clung to this idea, because come to think of it, I had never stumbled upon any that fitted that bill.

It was only when I started searching out the companies that process our food that I understood why: they prefer to keep a low profile, on industrial estates in amongst other anonymous, big box industrial units. Such locations give them the space and freedom to operate day and night. There are no immediate neighbours to complain about noise or smells. Heavy lorries can come and go, without drawing the ire of the local community.

Considering the volume of products they manufacture, there are surprisingly few of these factories in the UK: think in tens and hundreds, not thousands. On the chilled food front, for instance, in 2013, just 25 major chilled food companies operated from 100 highly streamlined production sites, employing around 60,000 people.

These factories supply supermarket chains that do not want the hassle of dealing with a plurality of small or medium-sized companies. With the exception of Morrisons, which is unusual in that it owns its own dedicated meat processing facilities, UK chains prefer not to get hands-on with the products they sell. Although 95% of the chilled prepared food Britain eats is sold under a retailer’s brand, supermarket chains do not own the factories churning out the food and drink that bears their names. Instead, they devolve that expense, responsibility and potential risk to third-party suppliers who work at arm’s length, according to the chain’s specification.

In order to squeeze economies of scale from their investment, food manufacturers need to be turning out products on a fairly constant basis to make good on their outlay and investment. Time is money. Stop-start processing plants without a full production schedule don’t make commercial sense, so these enterprises commonly supply not one, but several supermarket chains, to attain that critical volume. One shift, it will be Sainsbury’s ready-to-grill kebabs gliding along the assembly line, the next, meatballs for Tesco, or chicken pies for Asda. Even those processed foods that are sold as familiar household brands – as opposed to supermarket own-label – are commonly manufactured by a company other than the one with its well-recognised name on the box.

This is why third-party factories have innocuous, neutral names that give little or no clue as to the nature of the enterprise. If you drive past them, they look anonymous and blank, like vast storage units. Unlike the characterful brick and stone factories that still remain from Victorian times, they have no windows.