Never throw away the water in which fish has been boiled: it is valuable for making fish sauce, and also soup maigre. Therefore, in boiling fish, when the stock is or may be wanted, be careful about not putting in too much salt. Salt in quantity is not essential for boiling fish, and some fish will leave the liquor in which it was boiled a hard jelly when it is cold. This, of course, contains nourishment.

For reducing stock, see No. 26.