Why in English yougurt has first syllable stressed, while many other languages have last, and word has same Turkish etymology?
An exotic “health food” in the 1960s and 70s, yogurt only became a regular feature in supermarket dairy cases fairly recently. As a dairy product consumed in the Ottoman Empire, however, the first mention of yogurt/yoghurt in English occurs in the second volume of Samuel Purchas’s Pilgrims of 1625:
Neither doe they [the Turkish people] eate much milk, except it bee made sower, which they call Yoghurd.
Varied spellings throughout earlier centuries may suggest an aural phonetic transcription or different methods of rendering Turkish into the Roman alphabet before Ataturk’s reform.
In Old Turkish the yumuşak g, rendered as ğ in modern Turkish yoğurt, was pronounced as an English g, later, however, as a voiced velar fricative /ɣ/, and finally becoming silent in relatively modern times. Since /ɣ/ does not exist in modern English, the g-sound was as close as you could get. This would have been reinforced by the word’s pronunciation in, say, south Slavic languages whose speakers ate lots of yogurt, but which also had no /ɣ/ sound.
This sound change was reflected in a renewed borrowing of the term in the early 19th c. as — again, variously spelled — yaoort. Since the word with a not quite accurate g-sound could easily be pronounced — with the accent falling as in most native two-syllable words on the first — rather than a vocalic trainwreck representing modern Turkish, it’s easy to see why the former won over the latter.