Milk, for most people, just is. The only question beyond “Got Milk?” is “Whole or skim?” But as a recent Harrisburg debate proved, there’s nothing basic about the kitchen staple. There are dozens of shades of white: unpasteurized, pasteurized or ultrapasteurized? Grade A or Grade AA? Organic or conventional? From corn-fed cows or grass-fed cows? Produced using additional bovine growth hormone or without? Some of the farmers’ choices, you can taste: In a recent blind tasting, earthier, less sweet milk from grass-fed cows was a clear favorite, as was the higher-quality Grade AA. With their aroma of cooked milk, ultrapasteurized versions, which are superheated to extend shelf life, were the least favorite. And thankfully, Governor Rendell’s recent reversal of the state agriculture secretary’s decision to limit labeling means milk cartons can continue to list all the variables you can’t taste.