Science Behind it

There are many different factors that go into creating a highly marbled cut. For this reason it is difficult to attain and deemed exquisite.  The delicate balance between diet, breeding, and animal happiness determine the concentration of those fat cells that we want.  

• Diet: Grain-fed cattle tends to be more marbled than grass-fed. You can related this to your own life. You'd be much larger eating only bread and pasta compared to only eating spinach.
• Breeding: Not all species are created equal, at least when it comes to cattle. Genetics play an important role in determining how easily fat can be dispersed throughout their bodies. Selective breeding insures better marbling.  
• Animal Welfare: Stress is a factor to how soft and tender your meat will be. Stress sends a hormone called cortisol throughout the body, quickening the heart rate and hardening the muscles. This can also play a role in the cow's eating habits. Happy cows mean better meat.  

Finally, the type of cut you have also determines how marbled your steak will be. You can think of this as how certain parts of your body puts on weight differently. Its the same with cattle! For example a ribeye will be much more marbled than a top sirloin filet.