Probably nothing Dave not all carrots are a solid orange all the way through - you can get purple and yellow carrots too.

That too Snoop...

I planted Nantes for the first time this year, and have been surprised at their color: we definitely didn't pull them too soon, so it's probably just the way they are - amazing taste, though.

Thanks for your comments.
We will try cooking them and see how they taste.

Davegoldy