Formulation of Tengger Herbal Coffee: Effect of Coffee Type and Fennel Seed Powder

The Bromo Tengger Semeru National Park (or Taman Nasional Bromo Tengger Semeru/TNBTS) is a popular tourist destination in Indonesia, and the local authorities encourage the development of new local specialty products. One locally available commodity is coffee. This study investigated the best formula for Tengger herbal coffee. The randomized block design (RBD) consisted of two factors, including the coffee types (i.e., Arabica, Robusta, and Arabica:Robusta (50:50)) and the proportion of coffee:fennel seed powders (i.e., 92:8, 90:10, and 88:12). Physicochemical and organoleptic quality parameters were analyzed. In all coffee types, the addition of fennel seed powder at different concentrations significantly affects the sensory attribute (i.e., color, taste, and aroma) and the physicochemical characteristics of Tengger herbal coffee. The blending of coffee with fennel seed powder improved the taste and aroma of the herbal coffee. The best formulation was obtained from A3B3, a mixture of 44% Arabica coffee: 44% Robusta coffee: 12% fennel seed powder. This formula resulted in Tengger herbal coffee with pH 4.9, 16.6 color lightness, 0.64% total insoluble solids (TIS), 0.07% caffeine content, 47.2 mg GAE/g total phenol, 0.49 ppm antioxidant activity (IC50), and 0.58% reducing sugar. The findings confirmed that Tengger herbal coffee offers health benefits from its antioxidant activity, alongside the potential as a traditional beverage product.