Improvement of Bread Nutrition With The Addition of Coffee Silverskin as a Source Of Dietary Fiber And Antioxidants

Abstract

Obesity can be prevented by reducing the intake of high carbohydrates and fats, then replacing with high dietary fiber. Coffee silverskin is a by-product of coffee beans with high dietary fiber (54-74%) and antioxidants, which can potentially treat obesity. Indonesia has a traditional bread named "Gandjel Rel" from Semarang, which has a box-shaped, brown color with a sprinkling of sesame on the surface, and cinnamon flavor. The aims of this study are to increase its functional properties. In the bread making process, silverskin from Robusta coffee (Coffea canephora) flour is added with a variation of 0; 1; 2,5; and 5% (dw). The dough was baking at a temperature of 120˚C for 30 minutes. The bread was analyzed in terms of its dietary fiber, antioxidant activity by DPPH method, physical (hardness and color intensity), chemical properties (proximate), and sensory analysis. Bread with robusta coffee silverskin has higher dietary fiber (3,33-7,18% (w/w) insoluble fiber and 0,25-0,77% (w/w) soluble fiber) and antioxidant activity (26,23-31,36 g trolox eq./ 100 gr). Additional of coffee silverskin in the bread dough did not change the texture significantly, however, it did alter its physical appearance due to coffee silverskin’s brown color obtained from the coffee bean roasting process, so reducing brightness level and the yellowness of the bread. The panelists preferred bread by adding 1% robusta coffee silverskin. This bread has higher protein (11,33%, w/w), than conventional bread’s protein (8%). In addition, this bread contains dietary fiber and antioxidants, so it has the potential as a functional food.