London, England (CNN) -- On Friday in London's Trafalgar Square, 5,000 members of the public were served a free hot curry, free apple juice and an array of fresh groceries. The lunchtime feast, dished up by volunteers -- including the Bishop of London and the Mayor of London, Boris Johnson and -- was made entirely from ingredients that otherwise would have been wasted, such as fresh but cosmetically imperfect "wonky" fruit and vegetables that fail to meet the supermarkets' strict cosmetic standards. The event demonstrated how easy it is to reduce the unimaginable levels of food waste both in the UK and internationally, and how governments, businesses and individuals can all help to change the way waste has become rife in our globalized food chain.
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Central London event aims to feed 5000 people using food normally considered to be waste
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Edible food is often thrown away by businesses, restaurants and retailers
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Food sent to landfill decomposes into methane, which is 21 times more potent than carbon dioxide
In addition, around a ton of surplus apples was delivered to @placeholder so that passersby can press them to make fresh juice.