Food waste is a vast, global—and growing—problem. But for some fruit and vegetables, the solution may be as strikingly simple as being dipped into purified water.
Researchers on a recent study showed how dipping mangoes for a mere ten minutes into ozonated water enabled them to be refrigerated at lower temperatures after harvesting, which more than doubled their shelf life from 13 to 28 days.
The elegantly simple solution helps by solving an issue that is particular to mangoes and other temperature-sensitive tropical produce: these fruits struggle to ripen at temperatures below 13 °C and suffer an effect called ‘chilling injury’. This is a phenomenon that damages the flesh and skin, causing uneven ripening and unsightly marks, which often makes the fruits unmarketable. And yet, at 13 °C and above, mangoes are more likely to spoil, and so have a relatively short shelf life.
This puts mangoes in a tricky position and is part of the reason why 22% of all mangoes in Australia, where the study took place, are lost or wasted each year.
But the team of researchers from Australia’s Edith Cowan University were curious to see if they could reduce the fruit’s susceptibility to the cold, making it possible to refrigerate them along with other produce.
For this, they turned to ozonated water. This is liquid that has been infused with ozone gas, which is known to have powerful disinfectant properties and can reduce the presence of microbes on surfaces. In fact, the solution is widely used in the food industry to disinfect water and sanitize containers.
But the researchers suspected that ozonated water might have other benefits too, which they tested out on some recently-harvested mature green mangoes, from a variety known as ‘Kensington Pride’. Gathering together dozens of samples, they split the mangoes into three groups, and dipped them into ozonated water for ten, twenty, and thirty minutes respectively. Then they chilled the fruit far below their usual limits at 5 °C for 21 or 28 days. They also compared these three mango groups with a control group that remained undipped.
When they analyzed the dipped and chilled mangoes, it was clear they had some much more resilient fruit on their hands. The mangoes showed fewer signs of chilling injury, less weight loss—another symptom of damage during refrigeration—and were able to last up to 28 days in cold storage before being left to ripen as normal. In particular, the mangoes that had been dipped for the shortest period of ten minutes showed 40% less chilling injury than the fruit in the control.
When the researchers analyzed pieces of mango pulp from this group, they detected higher levels of specific antioxidant enzymes in the flesh, and this was a clue: “This initial stress triggers antioxidant production which in turn combats the chilling stress,” explains lead researcher Mekhala Vithana, a lecturer at the School of Science at Edith Cowan University.
Vithana and team found that the raised antioxidant levels help to protect and maintain the fruit’s cell membranes under cold conditions—which makes it less vulnerable to chilling injury and capable of withstanding lower temperature extremes.
Ozone bathing joins other unusual methods to prolong a fruit’s shelflife, such as treatment with melatonin, a sleep aid. The search for innovative solutions indicates the urgency to solve food waste, with mangoes being one particularly challenging example. In Australia mangoes contribute to 3% of the country’s greenhouse gas emissions from food waste, and worldwide mango production and associated waste is also growing, the study says.
Next, Vithana says they will be testing the ozonated solution on other mango varieties to spread the food waste-fighting benefit of their simple solution to the wider industry. “I think this will work for other tropical fruits and vegetables as well,” she notes.
Vithana et. al. “Postharvest aqueous ozonation alleviates chilling injury by upregulating ascorbate-glutathione (AsA-GSH) cycle and associated antioxidant enzymes in cold-stored ‘kensington pride’ mango fruit.” Plant Growth Regulation. 2025.
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