The Emerson quartet played with incisive tanginess, and Ms. Fleming, persuasively inhabiting a cabaret-size space, made her 10 minutes of singing count.

Mayonnaise supplies body, and sour cream or creme fraiche the requisite tanginess; buttermilk is too runny here, pleasingly American as it sounds.

Toss a handful of blueberries onto a spinach salad for tanginess, or make a trifle with strawberries, blueberries and a touch of homemade whipped cream.