Even the tastiest apple looks pretty unappetising if it starts turning brown.

But now experts may have discovered a way to prevent this from happening - and the results last for days.

Researchers have found that shining violet LED light on fresh-cut apples can stall the browning process.

And their discovery not only boosts the visual appeal and shelf life of freshly-cut fruit, but is an alternative technique to relying on chemicals.

In their study, the team 'treated' freshly cut apples with a 700 lux violet LED light for four days, and compared it to freshly cut apples which were simply stored in the dark for the same amount of time.

Pictures show that while the 'control' apple looks very brown by the fourth day, the light-treated apple still appears fresh.

Analysis revealed that the violet LED treatment reduced browning by boosting the accumulation of antioxidant-rich compounds while blocking the activity of oxidative enzymes which trigger the changes in colour.

Dr Aide Wang, from Shenyang Agricultural University, said: 'This research opens up exciting possibilities for the food industry.

'By understanding how violet LED light and specific transcription factors work together to prevent browning, we can develop more effective, eco-friendly methods to extend the shelf life of fresh-cut fruits without relying on chemicals.'

The researchers said the technology could easily be incorporated into existing food processing industries, reducing food waste and improving the appearance of other commonly-cut fruits including pears, melons and pineapples.

Writing in the journal Horticulture Research they said: 'Fresh cut fruit is popular. It meets customers' demands for freshness, nutrition and convenience.

'Fresh-cut friend accounts for 29 per cent of total fruit consumption in Europe and the USA, and 11 per cent in Japan and South Korea.

'Here, we discovered that violet LED light treatment significantly reduced fresh-cut apple browning. These results provide a theoretical basis for improving the appearance and quality of fresh-cut apple fruit.'