Beet--What Happened to the Red?

I had a successful planting of beets in the fall.  So successful, I decided to try to get another planting in.  So my beets have been in the ground, diligently growing. 

This morning I deemed the largest one ready for roasting.  Plucked from the ground, I broke off the leaves and heavy roots in the garden and popped them into the composter.  Into the house to remover the residual roots and leaves, wash off any remaining dirt, drizzle with olive oil, wrap in foil and into the oven at 400 degrees for a roasting.  (The skin is removed easily after roasting.) 
 
Imagine my surprise when my sharp knife cut through the flesh and revealed not a dark red beet, but a white beet with red markings.  It reminded me of a posting on Sunset magazine's blog about radishes with inconsistent coloring.

No one at Sunset had an answer.  Here are the variables which I can think of which might have caused this problem. 

1. Too cold
2. Too hot
3. Too rainy

I'm choosing too cold.  Some gardeners in zones which allow plants to live through the winter might be aware of cat-faced tomatoes.  I think just as a tomato which sets and grows in too cold of temperatures distorts, the beet does a similar distortion by not having consistent coloring. 

Any thoughts?
Follow up photo of beet after roasting. I am inclined to believe I have a different variety than the seed description.