Changing To Specific LED Bulbs In Your Refrigerator Can Double Berry Shelf Life
Moisture is the main cause of mold on berries. Many fungi are capable of rotting mature or near-mature fruits of strawberry, grape, raspberry, blueberry and blackberry. Serious losses can occur under favorable environmental conditions for disease development. Berry lovers rejoice as the days of unpacking your luscious berries from the refrigerator only to find them sprouting wispy goatees of mold may be numbered. A research team has demonstrated that low irradiance ultra-violet (UV) light at typical home refrigerator conditions--delays spoilage and specific LED bulbs may do the job.
New approach to slowing rot doubles berry shelf life.
The team from the U.S. Department of Agriculture’s (USDA) Food Components and Health Laboratory in Beltsville, Md., and Sensor Electronic Technology, Inc. (SETi) in Columbia, S.C., used a novel device incorporating light-emitting diodes (LEDs) that emit UV at wavelengths found in sunlight transmitted through Earth’s atmosphere.
The results, which will be presented next week at the Conference on Lasers and Electro-Optics (CLEO: 2013), are significant because previous attempts using traditional UV light sources for storage of produce resulted in severe drying, and it was unknown if the advantages of long exposure to low-level UV light would be effective against rot.
"The is potentially an effective, convenient and cost-effective method of reproducing wavelengths found in sunlight and duplicating that environment in your refrigerator," said
food technology specialist Hans Deh commenting on the research.
LEDs are now commonplace thanks to their long life and energy efficiency, as well as their ability to span the wavelength range from near UV to infrared. The full UV spectrum, however, had presented challenges for LED manufacturers -- until recently. SETi developed a special technology to fabricate UV LEDs across the entire UV spectrum from UVA to UVC. This flexibility allowed them to tune the emitted light to the wavelengths most effective for this application.
“UV-LEDs presented the opportunity to try low power devices that work well in the cold and can be engineered to work in small spaces such as refrigerator compartments,” says lead USDA researcher Steven Britz, who will present the work at CLEO: 2013.
Using strawberries purchased from a local supermarket, Britz’s team placed one batch in a dark refrigerator and one batch in a refrigerator exposed to UV-LEDs. Results showed the UV-treated berries had their shelf life extended twofold--nine days mold-free--over darkened berries, as judged by weight, moisture content, concentration of select phytochemicals, visible damage, and mold growth.
Based on these encouraging results, the team is working to commercialize the technology for home refrigerators.
“These findings are expected to have a major impact on the appliance business to extend the shelf life and preserve nutritional value of fresh produce while reducing waste and saving money for every household,” states Remis Gaska, president and CEO of SETi.
"Fresher is always better, but at least those who live in low occupancy households with
lower consumption (at least in terms of frequency), may throw out less berries with the new bulbs," said Deh.
John Summerly is nutritionist, herbologist, and homeopathic practitioner. He is a leader in the natural health community and consults athletes, executives and most of all parents of children on the benefits of complementary therapies for health and prevention.