Salami, the mystery meat: Is it cow? Is it pig? Well, if you’re talking Genoa salami, like you’d get at Subway, then it’s both. Most salami is made from slaughterhouse leftovers that are gathered using “advanced meat recovery,” which sounds like a rehab center for vegans but is actually a mechanical process that strips the last remaining bits of muscle off the bone so nothing is wasted. It’s then processed using lactic acid, the waste product produced by bacteria in the meat. It both gives the salami its tangy flavor and cures it as well, making it an inhospitable place for other bacteria to grow. Add in a bunch of salt and spices—for a total of 15 ingredients in all—and you’ve got salami. But now that you know what’s in there, you might need to check yourself into an advanced meat recovery center.