he is a familiar, paternal presence on the factory floor, where everyone calls him hamdi. >> hamdi ulukayaw you doing? >> kroft: he oversees every detail of a product line that barely existed a dozen years ago: greek style yogurt, a thicker, tangier version of the dairy product that ulakaya popularized here and named chobani. it's now the best-selling brand in america. what does the word, "chobani," mean? >> ulukaya: it means shepherd. >> kroft: shepherd? >> ulukaya: shepherd. it's a very beautiful word. it represents peace. and it meant a lot to me, because, you know, i come from a life with shepherds and mountains and all that stuff. >> kroft: his family raised goats and sheep and made cheese and yogurt in a small kurdish village in eastern turkey. during the summer months, they would move to the mountains and graze their flock under the stars. he says he was born on one of those trips, but he doesn't know the date or the year. so how did you come not to know your birthday? >> ulukaya: yeah, in the old days, you know-- the nomads, they didn't deliver babies in the hospitals. >> kroft: mi