Reductions are made to maximise the flavours of stocks and sauces. By boiling off the liquid component the flavours become more concentrated. If you reduce the volume down to about 10% you will have a very concentrated glaze, which can be frozen and used in a range of sauces. Another alternative is to make a reduction of a range of ingredients and add it to flavour a sauce. This process is used with Hollandaise sauce and applied to eggs Benedict.
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