Paper Title
The Result of the Substitution of Wheat Flour with Purple Sweet Potato Affecting the Quality of Muffin

The purpose of this research was to study of the appropriate amount of purple sweet potato substituted for wheat flour in muffin, which the percentages were 0 (control), 25, 50 and 75. The study found that the variation of the amount of purple sweet potato at different levels, the aditions of purple sweet potato were at the percentages 75 with statistical significance at the 95% confidence level. With the textural analysis using a Texture Analyzer, the results of the varying amount of purple sweet potato found that Springiness, Cohesiveness, Gumminess and Chewiness had similar value of control. And when adding more purple sweet potato, the hardness tended to increase. The chemical compositions of muffin made from purple sweet potato contained total calories, carbohydrates, fat, moisture, protein, ash and fiber anthocyanin, which were equal to 360.43 kcal, 30.04 g, 46.55 g, 17.47 g, 4.25 g, 1.39 g, 5.91 g, 1.33 g respectively, there was the amount of total anthocyanin at 5.08 mg/100g, total polyphenol at 174.53 mg eq GA, and total antioxidant activity (DPPH) was equal to 710.90 mgAA/100g. Keywords - Purple Sweet Potato, Muffin and Wheat Flour.