Researchers play spot the difference with browning bananas

Scientists from Florida State University (FSU) have been trying to spot the reason why bananas go brown and how to prevent these blemishes from leading to the fruit being discarded by retailers.

Each year tens of millions of tonnes of bananas are thrown away by stores. Their spotty exterior makes them less attractive to consumers who are unwilling to buy fruits that seem to be past their prime. Consumers find the brown bits of bananas so unappealing that in the UK alone over a million bananas are thrown away each day.

The FSU researchers wanted to understand the mechanics of bananas going brown, a process driven by air and enzymatic reactions, and used a mathematical model to see how and when the fruits changed colours. They found that the brown spots begin appearing over a two-day window, then spread quickly before mysteriously stalling for a period.

“Fruit browning continues to be a major challenge for the food industry. Our study offers a model for banana spotting which is capable of capturing their evolution in a physically meaningful context and which can be applied to procedures to mitigate food waste,” said Oliver Steinbock, lead author of the study.

The team of researchers went on to make suggestions for preventing fruit from being discarded for its natural browning process, noting that cooled storage in addition to other mitigation strategies and genetic modification to slow or prevent the process could reduce waste. For example, simply reducing the level of oxygen that the fruits are exposed to prevented brown spots appearing on the skin of bananas.

The study was published in Physical Biology and is available online.

Image credit: ©stock.adobe.com/au/bacothelock