The fridge that keeps things fresh for 500 years has me wondering how long Shinozaki is gonna live for (I forget if its been mentioned before) But I'm guessing with constant maintenance he is immortal.
In Japan people with noble or samurai ancestry often have names derived from the region their ancestors ruled over or were tied to in fealty. Originally their ancestors would have been known as Kurihara-no-xxx (xxx from Kurihara), then over time the "no" part denoting "belonging to" will be discarded and the regional name becomes a surname.