Researchers at Massachusetts Institute of Technology (MIT) and Singapore-MIT Alliance for Research and Technology (SMART) have developed a unique method to reduce food waste by using biodegradable silk microneedles to deliver melatonin into crops after harvest. The approach, tested on pak choy, a highly perishable leafy green, resulted in extending shelf life by four days at room temperature and ten days when refrigerated.
The study found that the low dose of melatonin delivered through the silk needles helped slow down the plant’s aging process, or senescence, without significantly increasing its natural levels. The team used fluorescent dye to show that the substances delivered reached all tissues, and applied melatonin-loaded patches by hand to monitor changes over time.
The results showed that untreated plants started yellowing within two to three days, while treated plants stayed green longer, maintaining their quality up to day 25. This method could be a game-changer in regions lacking refrigeration infrastructure, where every extra day of freshness counts.
The researchers aim to use tractors, drones, or other machines for more efficient patch application and plan to test other plant hormones and fresh crops to improve shelf life, texture, shape, and nutritional value. The goal is to make this technology widely adopted by farmers, reducing food waste and getting more fresh produce to people worldwide.
Source: https://www.earth.com/news/microneedle-injections-melatonin-keeps-fruits-vegetables-fresh-longer-reduce-waste