Most hamburgers are made the wrong way because chefs grind the meat with the wrong size plate, and get end up making the meat too fine and not coarse enough. When you grind the meat, use a 4/6mm plate and cut the beef into 3cm square chunks that has been cooled down to -1ºC. The machine should be cooled as well with ice cubes. These are important steps when passing the meat through the plates to get the right grind texture.
The next step is adding either cream, beer or other binders such as breadcrumbs, starch or egg albumin. Egg because of its protein concentration, is a powerful binding agent in food. It is the protein in the egg albumin that does this, making it one of our most valuable aides as a physical binder in cooking. But I believe temperature, coarseness and moisture levels of ground meat and other ingredients greatly influence the binding properties of a patty. If you get it right there is usually no need for a binding agent.
I do like to add some fat to give the hamburger a texture when it cooks, it gains flavour and should stays juicy.
Cutting Plates guidelines:
1/8″ (3.0mm) – Fine
9/64″(3.5mm) – Medium Fine
5/32″(4.0mm) – Medium
3/16″(4.8mm) – Medium Coarse
1/4″ (6.5mm) – Coarse
3/8″ (9.5mm) – Very Coarse, for pre-grinding