Hazrat Abu Hurairah radiyallahu anha says that he once saw Rasoolullah sallallahu alaihe wasallam eat a piece of cheese then perform wudhu. Then he saw him at another time eat a shoulder of a goat, and perform salaah without performing wudhu. (FR)
English reference (FR): Book 25, Hadith 167 (FR)
Arabic reference (FR): Book 26, Hadith 176 (FR)