Before you see these longer-lasting mushrooms at the grocery store or on your next salad or steak, though, they'll have to pass through other regulatory bodies first. Meaning, the Food and Drug Administration or Environmental Protection Agency could still put the kibosh down. Even that could take awhile however because of how slow bureaucracy moves: Penn State's Yinong Yang submitted his work October 30th last year and was only given the USDA letter of approval (PDF) this week.