With more than 1 billion meals thrown in the bin globally each day, there’s no doubt society needs new ways to cut food waste. Now scientists say they might have an answer – giving food products ‘sad’ labels to help us empathise with them.  Cartoons of sad-looking bananas boost sales of the fruit when they’re not in bunches, according to new experiments conducted in German supermarkets.

When people go to buy bananas, most are inclined to grab a bunch rather than several single bananas, according to the researchers. This picky consumer preference means single bananas are overlooked, tend to go black and are chucked away, contributing to the food waste problem.

The research suggests we feel sorry for food when it’s threatened with being thrown in the bin, but this can be alleviated by giving it a ‘good home’ – our stomachs.  ‘The need to belong is one of the most basic human motivations,’ said study author Dr Lisa Eckmann at the University of Bath’s retail lab. ‘Applying sadness to single, stray bananas evokes a compassionate response from shoppers.’

According to the UN, the world wastes 1.05 billion tonnes of food per year – a figure expected to double by 2030 – and households across all continents waste over 1 billion meals a day. This is a huge environmental problem because when food leftovers rot, they release methane, a powerful greenhouse gas that causes global warming.

As part of efforts to tackle the issue, Dr Eckmann worked with researchers in Germany to investigate the effect of ‘point-of-sale anthropomorphism’ – attributing human characteristics to objects for sale.  At a large food retailer in Germany called REWE, they gave single bananas their own shelf and set up various signs in front of them – ‘happy singles’, ‘sad singles’ and ‘no emotion’.

The ‘happy singles’ sign featured a banana with a smiley face speaking the words: ‘We are happy single bananas who want to be bought as well’. Meanwhile, the ‘sad singles’ sign had a sad-looking banana saying: ‘We are sad singles and would also like to be bought.’  Finally, the ‘no emotion’ had no face at all but included the words: ‘Here are single bananas that should be bought as well.’

The experiment was conducted over eight days for 12 hours each in two supermarkets of the same chain, yielding 192 hours of data collection. Overall, the researchers covertly observed the purchasing behaviour of single bananas of 3,810 customers over the course of 192 hours.

On average, the number of single bananas sold per hour was 2.02 when the faceless and emotionless banana sign was displayed.  The happy sign, meanwhile, led to an average of 2.13 single bananas being sold per hour – only a slight increase in sales.

However, the sad banana sign led to an hourly average of 3.19 single bananas sold – an increase of 58 per cent compared with the ‘no emotion’ sign. This suggests consumers do indeed feel sorry for inanimate objects in the supermarket – even food items that they will later take home and eat. Even though ultra-ripe brown and black bananas may not look as appetizing as their less ripe yellow counterparts, they are still fine to eat – as long as there’s no mould or signs of rotting (such as a funky smell). ‘The plight of the single bananas is really relatable and the findings have very practical applications for boosting sales and reducing food waste from our supermarkets. ‘The study shows it’s an easy, low cost, effective intervention for retailers and policymakers.’