Remove tinting from iOS TabBar

I have a TabBar at the bottom of my view that I dont want any tinting on. As od iOS 7, iOS automatically tints the icons blue and I dont want this to happen.

I have tried writing a custom renderer but setting the tint colour to clear simply removes the icon (should have seen that one coming).

protected override void OnElementChanged(VisualElementChangedEventArgs e)
{
    base.OnElementChanged(e);
    TabBar.TintColor = UIKit.UIColor.Clear;
}

I want to have an image for the tab item without any tinting. How can this be done?