Sparkles are often found in bright coffees. Hint: if you look at the cup of coffee and it winks at you, it has sparkles.: Sparkles is a key coffee quality term, and refers to brightnessA euphemistic term we use often to describe acidity in coffee. A bright coffee has more high, acidic notes. : A euphemistic term to describe acidity in coffee.... in the cup. Bright things often shine, both visually and in a gustatory sense, and that is expressed among tradespeople as sparkly, sparkles, or “this coffee is well-sparkled.” It is not related to crystals, as in the proprietary “flavor crystals”.