sour (adj.)youdaoicibaDictYouDict[sour 词源字典]
Old English sur "sour, tart, acid, fermented," from Proto-Germanic *sura- "sour" (cognates: Old Norse surr, Middle Dutch suur, Dutch zuur, Old High German sur, German Sauer), from PIE root *suro- "sour, salty, bitter" (cognates: Old Church Slavonic syru, Russian syroi "moist, raw;" Lithuanian suras "salty," suris "cheese").

Meaning "having a peevish disposition" is from early 13c. Sense in whisky sour (1885) is "with lemon added" (1862). Sour cream is attested from 1855. French sur "sour, tart" (12c.) is a Germanic loan-word.[sour etymology, sour origin, 英语词源]
stroganoff (n.)youdaoicibaDictYouDict
a beef dish cooked in sauce containing sour cream, 1932, from French, from name of the prominent Russian family, usually said to be for specifically in honor of diplomat Count Paul Stroganov (1774-1817).
fajitasyoudaoicibaDictYouDict
"A dish of Mexican origin consisting of strips of spiced beef or chicken, chopped vegetables, and grated cheese, wrapped in a soft tortilla and often served with sour cream", Mexican Spanish, literally 'little strips'.
bliniyoudaoicibaDictYouDict
"Pancakes made from buckwheat flour and served with sour cream", Russian (plural).
crème fraicheyoudaoicibaDictYouDict
"A type of thick cream made from double cream with the addition of buttermilk, sour cream, or yogurt", From French crème fraîche, literally 'fresh cream'.