Stocks made with raw bones produce scum. If the scum isn’t removed it will cloud and spoil the finished stock. Stocks that are prepared following the basic guidelines will be relatively clear. Most soups in this book don’t require crystal-clear stock, which is only important for consommés and other clear soups. For these soups, the stock has to be clarified after it has been strained and the fat has been removed.
Clarification involves a second cooking