Friendship bread

I made 4 loaves of Amish friendship bread. Two I followed the regular recipe and made cinnamon bread and two I made chocolate chocolate chip bread.
Both are delicious. But the chocolate bread separated a little. At least, the color did. The bottom inch or so of the bread is not the dark chocolate color of the rest. It's a brownish color. It still tastes the same and its really good. Just not the same color as the rest of the loaf. Any ideas or suggestions as to why that might be?