In a large bowl, dissolve the yeast in the warm water. Add the sugar and vegetable oil, and stir to combine.
Add the caraway seeds, cocoa powder, salt, all-purpose flour, and rye flour. Stir until a soft dough forms.
Turn the dough out onto a lightly floured surface and knead for 5 minutes, or until the dough is smooth and elastic.
Place the dough in a lightly greased bowl, cover, and let rise in a warm place for 1 hour, or until doubled in size.
Punch down the dough and shape into two loaves. Place the loaves on a lightly greased baking sheet and let rise for 45 minutes, or until doubled in size.
Preheat oven to 375°F (190°C). Brush the loaves with the beaten egg white and bake for 25 minutes, or until golden brown.
Remove from oven and let cool before slicing and serving.
Interesting Facts
Rye bread is a type of bread made with rye flour, which is a flour ground from rye grain.
Rye bread is a staple in many Central and Northern European countries, but it is popular in the United States as well.
Rye bread is high in fiber and B vitamins and has a lower glycemic index than wheat bread.
Rye bread has a distinctive flavor and texture, and is often served with butter, cheese, or deli meats.