Grenadine is a pomegranate syrup—or that's what it's supposed to be. If you've ever seen a pomegranate, you know that it's not an easy fruit to juice. So somewhere along the way, grenadine makers strayed away from using real pomegranate juice and instead used corn syrup and red dye #40. That's why a lot of us think of grenadine as "that sweet stuff that turns drinks red" and avoid it like the technicolor plague.
'grenadine' on Serious Eats
Jackson Cannon of Eastern Standard and Island Creek Oyster Bar in Boston describes the Jack Rose as "a lost classic." Constructed with house-made grenadine, Laird's Applejack, a bit of lemon, and a dash of Peychaud's bitters, it's spirit forward with a refreshing fruity undercurrent.