Updated! You can get the node and explanation here if you want to: http://www.blenderinsight.com/documentation-for-the-colorpeel-apple-shader/
Created an "Apple Shader" in Blender. 100% Procedural and it's easily adjusted to several different types of apples. I will post it for people to use freely on www.blenderinsight.com after the 17:th of September (a contest is ongoing on my FB group, so I can't reveal the nodes before that date). All images here uses the same shader with just different settings.