The Science of Better-Tasting Milk

There’s no use crying over spilled milk, but you might well shed a tear or two over the taste of milk in the era of plastic cartons. Scientists at Virginia Tech report that, in blind tastings, the flavor of milk stored in a standard supermarket-style dairy cooler is significantly degraded by fluorescent light passing through translucent plastic containers. When LED bulbs were used instead, tasters rated the milk about the same as when it was packaged in a lightproof container—which is to say, a lot better. The widespread adoption of translucent plastic containers almost certainly changed the flavor of milk for the worse. By now, she says, consumers mistakenly believe that this is how milk is supposed to taste. “Changes occurred in milk that affected flavor and quality after as little as four hours of light exposure, which were noticeable to untrained consumer panelists,” the scientists write. How does fluorescent lighting affect milk? Scientists say that its higher ultraviolet energy, among other characteristics, triggers a process of oxidation that damages essential nutrients, especially riboflavin, resulting in inferior flavor as well as a less healthful beverage. Over longer time periods, LEDs can degrade milk flavor as well, though not as much. Notably, neither kind of light makes milk go sour any sooner.