Braided Sweet Potato Bread

• 1 1/2 sweet potato
• 1 pkg dry yeast
• 1 soymilk for brushing loaves
• 375 gr wholewheat flour
• 240 ml soymilk
• 130 gr flour
• 45 ml honey
• 60 gr cornmeal
• 60 ml water
• 60 ml safflower oil