Banana spots can help reduce food waste, according to a study

Credit: Institute of Physics

Banana peels are the key to eliminating countless tonnes of food waste. New research published in Physical Biology explains and models the browning of this common household food.

A team of researchers from Florida State University has developed a new method for simulating the pattern of spots on bananas, thereby shedding new light on how this fruit browns over time. When many fruits are cut, damaged, or stored for extended periods of time, they turn brown due to air and enzymatic reactions. This results in an estimated 50 million tonnes of food waste, as stores and consumers discard bananas for aesthetic reasons.

“The estimated total production of bananas for 2019 is 117 million tonnes, making it the leading crop in the world,” says Oliver Steinbock, the study’s lead author. “When bananas ripen, they develop numerous dark spots that are recognisable to the majority of individuals and are frequently used as a ripeness indicator. Until now, however, the process by which these spots form, expand, and acquire their pattern was poorly understood.”

Steinbock, along with co-authors Qingpu Wang and Pamela Knoll, examined how spots form and change over time using time-lapse videos. Using a nonlinear reaction-diffusion model that takes into account the oxygen concentration and degree of browning of the peel, they discovered that the spots appear during a two-day window, expand rapidly, and then mysteriously stop.

The team then examined the root cause of the spot stalling, which suggests mitigation strategies for the browning process that could compete with genetic modifications and storing the fruit in cooled containers or an altered atmosphere. They discovered that the formation of spots can be slowed by reducing oxygen levels in their microscopic formation sites.

“Fruit browning remains a significant problem for the food industry. Our research provides a model for banana spotting that is capable of capturing their evolution in a physically relevant context and can be applied to procedures to reduce food waste “Steinbock summarises.

Further information: Oliver Steinbock et al, Front-like expansion and arrest of programmed cell death in brown banana spots, Physical Biology (2022). DOI: 10.1088/1478-3975/ac664d

Journal information: Physical Biology

Source: Institute of Physics