In a bid to tackle the pervasive problem of food waste, researchers at MIT and the Singapore-MIT Alliance for Research and Technology have come up with a novel solution that could keep your greens greener for longer. As per an article from MIT News, this new technology uses biodegradable microneedles to inject harvested plants with melatonin, potentially revolutionizing the way we store and transport produce.
Food waste is an issue with serious implications, and more than 30% of the world’s food never makes it from farm to fork, this statistic becomes even more dire when considering how this wasted resource could feed upwards of 1 billion people. This innovation is particularly important since numerous regions, especially in developing countries that produce a tremendous volume of crops, lack the energy and infrastructure for proper refrigeration. Associate Professor of Civil and Environmental Engineering at MIT, and director of the Wild Cards mission of the MIT Climate Project, Benedetto Marelli told MIT News, "The food we waste could feed about 1.6 billion people. Even in the U.S., this approach could one day expand access to healthy foods."
The researchers' approach hinges on the use of silk microneedles that seamlessly penetrate the plant's robust exteriors without triggering stress responses. In a study published in Nano Letters, the team, led by Marelli, applied patches of microneedles containing melatonin to pak choy—a leafy vegetable chosen for its perishability and significance in Asia. The results were promising: the shelf life at room temperature extended by four days, and by a substantial 10 days when refrigerated.
"Post-harvest waste is a huge issue. This problem is extremely important in emerging markets around Africa and Southeast Asia, where many crops are produced but can't be maintained in the journey from farms to markets," Senior Principal Investigator at the Temasek Life Sciences Laboratory in Singapore, Sarojam Rajani, reiterated the potential impact of the method in regions that struggle with post-harvest losses. In experiments, the treatment helped maintain pak choy's weight, visual freshness, and chlorophyll concentration—a critical indicator of health as plants age, without the leaves beginning to yellow within the first few days as untreated controls did, showing the method's efficacy even without refrigeration, as per MIT News.
The method also showed promise under cooler temperatures. "In refrigerated conditions of about 40 degrees Fahrenheit, plant yellowing was delayed by about five days on average, with treated plants remaining relatively green until day 25," reported Monika Jangir, co-first author and former postdoc at the Temasek Life Sciences Laboratory. While the findings have sparked optimism, Marelli acknowledges that more work is needed before such a system could be widely implemented, including automated application processes via tractors or drones and cost-effectiveness evaluations. "For this to be widely adopted, we’d need to reach a performance versus cost threshold to justify its use," as detailed by MIT News.
Going forward, the team plans to explore the effects of different hormones on a variety of crops. If the technology can be scaled effectively, the days of tossing out limp lettuce or moldy berries may be numbered, potentially making a significant dent in the global fight against food waste.
