The so-called "time-poor, cash-rich" equation has thrown up some interesting food innovations. Ready-sliced carrots. Broccoli florets. Diced onion. Celery sticks. Ready-mixed stir-fry ingredients.
And, of course, the bagged salad. This is the big one as far as supermarkets are concerned: a veritable green goldmine. In the UK, the market analyst TNS estimated that the market for bagged salads stands at over £256m (some estimates put it much higher), and that 69 per cent of British households buy them, on average, once a month. What is more, bagged-salad sales are growing at seven per cent a year. The two biggest sellers are Tesco and Sainsbury's, with the other supermarkets coming up behind. It's a similar success story in the US, where the bagged-salad market is estimated to be worth $1.2bn per year.
It isn't hard to see why sales of bagged salad have soared. Although raw, it is convenient - even aspirational, as if bringing a restaurant into the home. Bagged salad often offers the consumer different types of leaf in the same bag: good for meeting your Government-suggested five daily fruit and vegetable requirements. It offers the appeal and appearance of healthiness and hygiene - not to mention the straight-to-plate ease of it all. So, why does bagged salad have such an image problem?
It probably started with Felicity Lawrence's 2004 book, Not on the Label (Penguin, £7.99), which, among other food-industry staples, took on bagged salad. Among the various issues highlighted by Lawrence were that bagged salad was expensive, wasteful and often prepared by poorly paid migrant workers. Phrases such as "sweatshop salad" began to be heard. Although sold in Modified Atmosphere Packaging (MAP) to keep it fresh, Lawrence wrote that such salads' nutritional value deteriorated in the bag, supported by a 2003 experiment in Italy that found that nutrient levels dropped off sharply after bagging. And it was often washed in a chlorine solution of a greater concentration than the local swimming pool.
If all that wasn't enough, when bagged salad came on to the scene in the early 1990s, there were some issues with bacterial infection. No doubt about it - reading Lawrence put you off bagged salad.
Since then, the theme has been widely picked up. In the "Living" section of the Friends of the Earth's website, we are urged to be "Salad Savvy": "If you can't buy - or grow - chemical-free salad ingredients, avoid the bagged stuff and opt for loose ingredients when you go shopping." While the WWF-UK website alerts readers to the environmental problems associated with providing irrigation water for Spain's salad corridor in Murcia, where much of the crop for the UK's bags is intensively produced.
There are intriguing cultural arguments against bagged salad: namely, that it is part of the convenience culture that has brought down the average meal time to 20 minutes; and that has drawn people away from preparing their own food, thereby de-skilling domestic life. "I do think that bagged salad represents all that is, arguably, wrong with our current food culture and food system," says Wendy Fogarty, the UK spokeswoman for the Slow Food movement. "From a culinary perspective, it's also sad that salad is now largely limited to leaves - historically, roots, stems and edible flowers featured in English salads, and the use of root vegetables in salad provided more choice during the autumn and winter."
Flown-in bagged salad also scores on food miles, and runs against the increasingly prevalent notion that we should eat according to season. Another aspect lies in the supermarkets and their tendency not to sell "loose" food. "Multiples have environmental- health considerations that mean that food is sold in packs," says Fogarty. "We have become slaves to convenience and have lost a respect for food."
Another charge is that bagged salads are a manifestation of the disconnection between the consumer and the farm. "Our ideal situation would be that people bought salad in a more primary state and prepared
it themselves," says Phil Stocker, the head of food and farming at the Soil Association. "It creates the link between people and their food, and encourages local-produce buying." And while he accepts that some food must be imported, he feels that intensive salad farming, with its polytunnels, lump labour and just-in-time practices can give rise to "landscape problems".
Add chemical problems to the toxic mix, too. "Lettuce as a crop uses high pesticides, which is one problem," says Barbara Dinham, director of the Pesticide Action Network UK. "Chlorine washing is another." Some prefer to use ozone-washing and have modified the chlorine, but environmentalists have argued that these are processes that disarm the natural act of spoilage: God's way of telling you that grub is off.
Thus has bagged salad, in a few short years, become a cipher for all the perceived ills in mass food production. Can it really be that bad? The bagged salad industry doesn't think so, and got together this year to launch a publicity campaign on behalf of the big salad-baggers - Geest, Natures Way Foods, Vitacress Salads, Fresh Del Monte, Florette, Kanes Foods, known collectively as the "Fresh Prepared Salads Producer Group" - aiming to convince consumers that bagged salad is good, and
also to counter what its spokeswoman calls "myths and misconceptions". "It's a great shame that people have been put off salad bags," she says. "We have research that shows that more people eat salad as a result of bags. Plus, you get a mixture of leaves in bags: all kinds of brassicas, watercress, spinach and Far Eastern leaves such as tatsoi and mizuna. You wouldn't have seen rocket in supermarkets until salad bags came along." And, she claims, salads do pretty well in food miles compared to other foodstuffs.
Brigid McKevith, senior nutrition scientist with the British Nutrition Foundation, isn't convinced by the anti-baggers either. "I'd be happier that people bought bagged salad than not at all," she says. "Bagged salad allows people to get their five-a-day, and remember, 20 years ago, salad was just lettuce and tomato with a dollop of salad cream. Also, bagged salad has contributed to people eating salad all year around."
Jeremy Boxall, of the farmers' group Leaf (Linking Environment and Farming), supplies salad to Waitrose and Marks & Spencer, and says that the salad in British bags is still grown predominantly in the UK, but that from October to May, production shifts to Spain, Portugal and Africa. "I've been impressed with the environmental management there," he says. "The standard of production is very high and overseen by our producers to the standards we'd demand here." If salad was grown in the UK to satisfy year-round demand, then eco-unfriendly greenhouses would have to be used.
Moreover, the Fresh Prepared Salads Producer Group doesn't think that we should worry unduly about chlorine washing: "In the vast majority of cases, no detectable chlorine residues were found, and when they were, it was as little or even below that which is permitted in tap water," says the spokeswoman. Nor should we even fear the sinister-sounding Modified Atmosphere Packaging, which the group tested. "The MAP thing is nonsense," says Kaarin Goodburn, secretary general of the Chilled Food Association, who believes that the Italian experiment that gave rise to the earlier fears was flawed. "It's disturbing to see so much negative information, especially when people across the world are trying to emulate our food industry and practices."
As to the charge that people buy bagged salad because they don't understand food - well, that might be the one point upon which the two sides of the argument concur. "It's true that we don't take a positive enough interest in food," says Goodburn. "Sadly, intake in food-science degrees have plummeted. How many people know how long it takes to raise a baby spinach leaf, for instance?"
Whichever side you take - and the salad skirmish will no doubt continue - the bagged salad will be remembered as a milestone in British food education.
From plot to plate
* Seeds are planted in UK farms or, out of the normal growing season, in intensive farms in Spain, Portugal and, to a lesser extent, Africa, clocking up hundreds of food miles by the time they reach your table.
* The leaves take a couple of weeks to grow. During the colder months, they are grown in polytunnels, which blight the landscape and contribute to global warming.
* The intensive-farming environment, and the supermarket consumer's expectations of "perfect" leaves mean that multiple pesticides need to be liberally used.
* The salad is (usually) washed in chlorinated water to take away traces of earth and any bacteria or contaminants.
* The leaves are cut, sorted and packed, often by cheap, casual (largely migrant) labour, and often in harsh conditions.
* The salad is bagged in modified-atmosphere packaging, using altered levels of carbon dioxide and oxygen. This can keep it looking fresh for up to 10 days.
* It is then freighted to British supermarkets and sold.
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