It seems pretty much impossible, however well you plan, to do one big shop a week and expect that all the food will still be usable by the time you decide you want it. In families where there are parents who both work full-time, a plea for mitigation is that there's little time to plan better and shop more often for smaller quantities.

Short shelf life, stressed lives, over-purchasing, inefficient storage and cooking food in excessive quantities yet not using leftovers... all of these contribute to the shocking mountain of food waste generated each year in the UK.

That mountain weighs roughly 6.7 million tonnes – enough to fill Wembley Stadium eight times. For every three bags of food we take home, one will be discarded and end up as landfill. Over Christmas alone, around 230,000 tonnes of food worth about £275m that could have been eaten was thrown away. Roughly 70 per cent of it could have been eaten perfectly safely, say campaigners, and represents a spend of between £250 and £400 a year per household.

So, as a nation, we're stupidly wasting around £8bn a year on food we don't eat, which is then heaped in with the rest of our household waste and compacted into landfill sites, where it produces the potent greenhouse gas methane because it cannot "breathe". Methane is 23 times more harmful to the atmosphere than carbon dioxide.

Saving the energy needed to produce, package, transport and deliver this food would reduce the generation of carbon dioxide by
15 million tonnes a year – the equivalent of taking one in five cars off the road. Worth doing, right?

Yet, according to a poll done by the Government-funded Waste and Resources Action Programme (Wrap), nine out of 10 people haven't the foggiest idea how much food they throw away. That's why an awareness campaign like Love Food, Hate Waste is so badly needed, says Mark Barthel, special adviser to Wrap.

"There's no silver bullet on this. It's about understanding consumer behaviour for a start. Different segments of the population waste for different reasons: young working people do so because they generally have no home economy skills and don't know how to store and cook food. They also have unpredictable lifestyles.

"With young families, it's more about an extreme sense of food safety, where 'best before' is treated the same as 'use by'."

But you don't have to have small children (or an elderly parent in residence) to be confused about these food labels. "'Use by' affects fish, meat and dairy products, and means you really shouldn't use the food after the date shown.

"'Best before' is a label used more on foods with a longer shelf life, and means that although the food will be at its best before the date shown, it is still usable afterwards. Wrap is working with the Food Standards Agency and retailers to try and make the distinction clearer." (In the meantime, see the box below.)

About 40 per cent of the food we throw away is down to cooking too much and discarding the excess. The Wrap website (www.wrap.org.uk) provides a handy portion calculator for most common foods.

We are a lot more wasteful with food now than in times gone by, but, paradoxically, more aware of the economic, environmental and moral evil of being so profligate.

Much of the geology of the UK does not lend itself to use as landfill, even if such use were allowed. Some of the Home Counties are running out of landfill, and shipping their waste out to adjacent authorities at enormous cost. Ideally, landfill should be seen only as a last resort, and the EU landfill directive has laid down targets for incremental landfill reduction, by 2010, 2013 and 2020. By 2020, the current 22 million tonnes of degradable household waste should be reduced to 6.9 million tonnes.

Wrap, which is funded by the Department for Environment, Food and Rural Affairs (Defra), is looking into many uses for biodegradable food waste, such as processing to create domestic heating, cooking or chilling of food, or helping to feed an anaerobic digestion plant (currently featuring in a storyline in Radio 4's The Archers) to produce energy.

Last year, Wrap chose Calderdale and 16 other local authorities across the country as test beds for a scheme it part-funded to collect and process discarded food separately from other household waste. Over the 40-week trial, which finishes next month, more than 6,500 households in the Todmorden and Park wards are participating.

Each home uses a small caddy lined with a biodegradable corn starch bag (provided for free) to collect food waste including peelings, carcasses, etc. The liners then go into a larger container kept outside and emptied weekly. Waste is taken to a processing plant at Todmorden, where it's mixed with wood and garden waste to make a bulk commercial soil improver for farms.

"The trial has resulted in 10 tonnes of waste a week being diverted away from landfill," says Calderdale's waste manager Malcolm Akroyd. "In the summer, the figure was more like 11 or 12 tonnes. We're not sure why the figure is less in winter – maybe we eat less in summer, and food doesn't go off so fast in winter."

The authority hasn't published its final report on the trial, but despite the comparatively high cost of separately collecting and processing food waste – currently £160 to £190 per tonne compared with approximately £100 per tonne to collect and dispose as landfill as part of the normal waste collection service – both users and the authority are pleased with the service. Wrap has provided £130,000 towards the costs over two years. "It has made me much more aware of what I'm doing with food," says one female resident of Todmorden. "Until the trial, I had no real idea of the huge amount we as a family were wasting, and it made me vow to buy only what I need for particular meals, do a top-up shop of fresh food midweek, and to pay a lot more attention to freezing what I can.

"I've noticed over the months that we've taken longer and longer to fill up the caddy, and I feel quite saintly, to be honest."

The authority's cross-party Health and Social Care Scrutiny Panel is now considering recommendations to extend the food waste collection service to almost all of Calderdale's 90,000 households.

By 2010, the cost differential between disposal in landfill and processing costs for recycling food waste are set to decrease because of the effect of the Landfill Tax Escalator.

"With 25-30 per cent of landfill currently being food waste, naturally local authorities are keen to get it out of the general household bin," says Mark Barthel. "And, of course, it's in everyone's interests."


UNDERSTANDING THE FOOD LABELS
Use-by: This is the key date in terms of safety – never eat products after this date and observe storage instructions. Check if the food can be frozen if you need to eat it at a later date. "Use by" dates are usually found on chilled products such as cooked meats, soft cheeses and dairy-based desserts.

Best before: "Best before" dates are usually on longer shelf life foods such as frozen, tinned or dried goods, and refer to quality rather than safety. So it's best to use your judgment. It should be safe to eat food after the "best before" date, but food may no longer be at its best. Eggs are an exception, never eat them after the "best before" date.

Display until/Sell by: These often appear near or next to the "best before" or "use by" date. They are used by some shops to help with stock control and are instructions for shop staff, not shoppers.
Source: Food Standards Agency

HOW TO CUT FOOD WASTE
Polly Brown
Supermarkets keep fruit and veg in the best conditions they can to keep them fresher for longer. Replicate at home by keeping these foods cool, where air can circulate and out of sunlight. However, it's good to be able to see fruit and veg – so that you are tempted to use them!

When buying food – especially two-for-one offers – think, "Do I need this?" Think quality, not quantity.

Shopping every day is not feasible for most people, but two or three times a week is good.

Plan ahead as far as you can, but don't ignore foods which are in season or you may have forgotten about. Buy foodstuffs that stimulate you to want to cook them within a day or two.

"Make do" a bit more – don't just buy a lot of food, think frugal and simple.

Downsize your larder: do you really need half a dozen types of oil/vinegar?

Make a list of food you regularly throw out and stop buying it or reduce the amount.

Overhaul the fridge regularly, at least twice a week, checking for items close to their "use-by" date.

Make a meal of items you have in, eg soup, or risotto from rice, onion, glass of wine (optional), stock cube, bacon and grated cheese. Always keep foods that will make a quick meal – bacon, cheese and eggs are ideal.

Get a dog – lots need homes!