With a Good Dunking, Just-Cut Produce Stays Fresher Longer

Fresh produce lovers: Put away those paring knives. Thanks to new food processing technologies being developed by Agricultural Research Service scientists, there may no longer be a need to engage in all that tedious peeling, chopping, slicing and dicing.

As Americans are being encouraged to boost their consumption of colorful fruits and vegetables, ARS researchers are developing methods to ensure the quality of ready-to-eat produce. Their work will hopefully make it easier for consumers to get healthy foods.

At ARS' Southern Regional Research Center in New Orleans, La., chemist Olusola Lamikanra has developed three techniques for prolonging the shelf life of already-cut fruits and veggies. These methods should help expand the fresh-cut produce supply, which is already one of the fastest growing food categories in U.S. supermarkets.

All of Lamikanra's methods center on one goal: keeping plant tissues from getting stressed out.

When plant cells detect a nearby injury, as occurs with slicing, they shoot off a flurry of electrical, chemical and hormonal signals. These signals initiate defense responses that serve to protect the plant. But such wound signaling also results in noticeable changes to a plant tissue's texture and chemical properties.

As Lamikanra has found out, one way to bypass the plant's alert system is to slice the fruit while it's held under water. This way, the plant's tissues aren't able to detect the changes in pressure that would otherwise accompany the slicing. The water forms a barrier that prevents the movement of fluids out of the fruit or vegetable tissues being cut.

Heat and UV light treatments can also be used to fool a plant's defense system and to keep just-sliced fruit crisper and more flavorful.

ARS food-sensory expert Karen Bett-Garber, who leads volunteers in taste tests of cut melon, confirms that the new methods are helping cantaloupes stay fresh, with their quintessential melon flavors lasting longer.

To learn more about this research, see the current issue of Agricultural Research magazine.

ARS is the U.S. Department of Agriculture's chief scientific research agency.