The main thing to understand about a Consomme is the reason why your doing what your doing. Once you understand the process of the "raft" and achieve a clear broth, you will be happy. A good Consomme is a labor of love and understanding, just like a good marriage....................ChefBillyB
I think Emeril gives you a good idea on how it works in this recipe
Take a soup stock and make a clarrification. Start with a large pot of cold strained stock . In a large bowl mix together a mirepoix with egg white, shells and lean ground beef and or veal and beef. and bouquet garni SIMMER GENTLY about an hour and a half . DO NOT STIR OR BOIL. With a ladle make an opening in all the scum which will come to top . Set up another pot with china cap and cheesecloth then ladle the clear liquid(consomme) from the first pot to the second, through the china cap then correct seasoning Wella!! Consomme now add appropriate garnish. It is easy. They sell a consomme pot wich has a spigot on bottom so the claer consomme can exit thru there instead of ladeling off.
A strange thing happened the other day. I bought some chicken backs and wings to make chicken broth but didn;t have time and froze them. I put them in frozen - put in the cold water and turned on the gas, intending to lower it after it started getting warm but forgot. I also forgot to skim. It has boiled some ten minutes. Lowered the heat (all the scum had been reabsorbed) and simmered slowly for a couple of hours, maybe 3.
It was a PERFECTLY clear - I don't understand why. It was also incredibly good. I wonder why? Sometimes i hover over it and try to catch all the scum and keep it just under the boil and it isn;t particularly good nor is it so clear. I don;t mind the cloudiness but i did like this one that was so incredibly clear.