Way to increase freshness of fruits, vegetables


An innovative method developed by an American professor can help fruits and vegetables retain their freshness. Millions of tons of fruits and vegetables are dumped every year just because they are too delicate for handling or have a short shelf-life, says the US Department of Agriculture.

The method devised by George Pierce, microbiology professor at Georgia State University (GSU), will allow fruits, vegetables and flowers to retain freshness for longer periods, making storage at room temperatures possible, bypassing refrigeration altogether.

Climacteric plants like apples, bananas, peaches and tomatoes, respond to climactic change, producing increased levels of signalling compounds like ethylene. In the case of peaches, ethylene causes them to ripen, increases aroma chemicals, but unfortunately, makes the peach very fragile. “If you’ve seen ripe peaches, they will simply fall apart,” says Pierce. “It will lose 90 percent of its ability to resist pressure, which means that if a peach responds normally to ethylene, it is subject to bruising when you ship it,” Pierce added.

Pierce’s method relies on a naturally occurring micro-organism, just the width of human hair, to activate enzymes that double the ripening period of fruits, vegetables and keeps flowers fresh. This new process could have a big impact on preventing waste, improving the consumption of healthy fruits and vegetables, allowing companies to ship produce for longer distances.

The process does not involve genetic engineering or pathogens, but involves micro-organisms known to be associated with plants. “These beneficial soil micro-organisms serve essentially the same function as eating yogurt as a probiotic to have beneficial organisms living in the gastrointestinal system,” Pierce said.

“We change the diet of the organism, and we can change its performance,” Pierce said. “It’s no different than taking a good athlete and putting them on a diet and exercise regime, and turning him or her into a world-class athlete.” Pierce added.