Researchers in Cornell University's Department of Food Science have been studying the way milk products change with exposure to LED lighting, an increasingly common light source for refrigerated display cases in grocery and convenience stores. What they've found isn't all that encouraging for further growth of that market.
[Researchers] found that exposure to light-emitting diode (LED) sources for even a few hours degrades the perceived quality of fluid milk more so than the microbial content that naturally accumulates over time. Their study determined that milk remained at high-quality for two weeks when shielded from LED exposure, and that consumers overwhelmingly preferred the older milk over fresh milk stored in a typical container that had been exposed to LED light for as little as four hours.
Exactly why the lighting is changing the milk products isn't entirely clear yet, but there's hope that the source of the problem lies in the color spectrum produced by the LEDs. If so, LED manufacturers are likely to find a better way as manipulating color is one of busiest areas of research right now.
LED lighting produces a pattern of wavelength that differs from the fluorescent bulbs that have been used to illuminate display cases. LEDs typically emit in the blue spectrum, around 460 nanometers, and produces a broader emission peak than fluorescents. That peak in LED light is near the narrow band where riboflavin absorbs light, a fact the researchers surmise could be selectively destroying the nutrient and damaging the perceived quality of the milk.
