- Our Black Walnut Sumatra Decaf coffee is a naturally flavored, decaffeinated premium Sumatra coffee combined with Black Walnut Leaf, Walnuts and Rose Petals. You will enjoy the lovely full-bodied, low acidity Black Walnut coffee taste! - Ingredients: Decaffeinated Sumatra coffee (whole coffee beans), Black Walnut Leaf, Walnuts, Rose Petals and Natural Black Walnut Flavor.