Ask Marilyn

I buy organic milk because it lasts much longer. Is this because it has fewer impurities? —Ashley Metzger, Orlando, Fla. No. The reason is most organic milk is pasteurized with an ultrahigh temperature (UHT) process because it must travel farther to reach store shelves. So why isn’t all milk ultra-pasteurized? Because the process, which heats the milk to 280 F, gives it a “cooked” and slightly sweet flavor (from burning some sugars) many consumers find less fresh-tasting. If you’re interested only in shelf life, you can buy non-organic UHT milk at half the price. Regardless, once you open any kind of UHT milk, it starts to lose its long-lasting quality.