Jon and Greg discuss the two kinds of dairy pasteurization, HTST ("high temperature, short time") and UHT ("ultra high temperature"), or ultra pasteurization. UHT pasteurization developed in the 1960s and allowed the shelf life of dairy products to be extended threefold, a convenience for milk manufacturers. But Jon and Greg aren't buying it. Greg finds that ultra pasteurization strips milk of its flavor, and Jon is suspicious of milk that, according to its packaging, can last up to nine months unopened. "Something that's nine months old is NOT fresh," he observes.