Experts now say that fruit and vegetables, still alive after being taken from the ground, respond to changes in levels of light by producing different levels of goodness. The process has been demonstrated by observing plants in the wild, which produce more nutrition during the day than at night. What this points to is the possibility that keeping foods in a fridge may speed up the demise of a vegetables' nutritious content. Researcher Janet Braam, a professor of biochemistry, said: “Vegetables and fruits don’t die the moment they are harvested. “Perhaps we should be storing our vegetables and fruits under light-dark cycles and timing when to cook and eat them to enhance their health value.” Working on shop-bought cabbage, the professor showed that levels of chemicals called glucosinolates rise and fall over a 24-hour period – as long as the vegetables are exposed to periods of light and dark. Glucosinolates are bitter-tasting compounds found in particularly high quantities in cabbage, broccoli, cauliflower and sprouts and are known to have health benefits, contributing to disease prevention. The journal Current Biology reports that, in cabbage at least, levels of health-boosting glucosinolates are highest around lunchtime. The professor said: “One of the reasons you are told to eat cabbage is because cabbage has chemical compounds that act as potent anti-cancer agents." “What we’ve shown is that these anti-cancer compounds also cycle on a daily basis if the vegetable is kept under light-dark cycles to keep its circadian clock functioning.” She said that it is too early to say just what time we should eat various types of fruit or vegetable to get the most goodness. If timing our meals around chemical production is too difficult, it may be possible to freeze crops at the time of day when levels are at their highest. More research is also needed to work out what pattern of light and dark maximises the production of healthy chemicals. If this can be determined, it might be possible to create fridges with internal lights that switch on and off at the required times. Source: iol.co.za. Source: Fresh Plaza
