This section is from the book "Diet In Sickness And In Health", by Mrs. Ernest Hart. Also available from Amazon: Diet in Sickness and in Health.
After having insisted, as I have done, upon the necessity of diminishing the intake of food, particularly of albuminous foods, in old age, it will not, I think, be out of place if I give a few recipes to show how the aged may be well fed on a light diet. Fish and poultry should take the place of butcher's meat. Besides the ordinary methods of boiling, frying and baking fish, soups and delicate dishes may be made of fish, which will be found to be not only appetising but satisfying to those on whose muscular powers but slight demands are made. Fish contains a third less of albuminoids than ordinary meat, and is hence very suitable as an article of diet for the old. Sir Henry Thompson, to whose scientific and practical studies on food we owe so much, points out that, besides the well-known sole, turbot, salmon, whiting, haddock, mackerel, cod, trout, smelt, herring, skate, and mullet, there are other kinds of fish admirable for food, which yet are almost totally neglected by the British housewife. These are the wolf-fish or cat-fish, the halibut, sea bream, bass, gurnet, ling, hake, thornback, pollock, and coal-fish, to which may be added the conger, excellent for making soups and stews, and the sturgeon (of which the flesh approaches that of meat in quality). The following are Sir Henry Thompson's recipes for fish soup: -
1. Put three ounces of butter into a stewpan, add two carrots sliced, one onion, and a shalot in thin slices, then cloves, a little thyme, and some parsley. Fry them gently until of a reddish tint, then add three pints of cold water. Let it boil, skimming occasionally. Then add a small fresh haddock, bones and all, cut up into pieces, and the head and bones of two whitings, setting aside the fillets; a cod's head or that of a turbot, or the fresh bones, head, and fins of two large soles, the fillets of which are required for another dish, may take the place of the foregoing. Add some salt and a little pepper. Let all simmer together for two hours gently at the corner of the fire; take out the bones, and pass all the rest through a coarse strainer. Divide the fillets of whiting into two or three small portions each; boil for a few minutes in some of the stock, add a little fresh green chervil and parsley chopped not too finely, and serve all together in a tureen. This soup may be thickened if desired by adding a tablespoonful of white " roux," that is a little flour well mixed with butter in a stewpan over the fire, cooked but not allowed to brown. This is unquestionably an improvement. Fillets of other fish may be substituted for those of the whiting, or a few shell fish or oysters if they are well digested.
The following is the receipt for an economical fish stew: -
2. Take three or four pounds of hake, ling, skate, or haddock, and one pound of " cuttings or trimmings," which are the best part of the fish for stock making. Remove all the fish from the bones, break up or pound the latter, and set aside with any portion of head there may be and the cuttings. Put into a saucepan over the fire two ounces of lard and two or three onions sliced, and let them fry until brown; then add two quarts of water and all the pounded bones and trimmings, some parsley or other green herbs, pepper and salt. Let the whole simmer for three hours, adding the amount of water lost by evaporation. Strain out the bones, bits of skin, etc., add the fish in pieces, and boil gently ten or fifteen minutes. Thicken with sufficient flour mixed smoothly with a small portion of stock, and added before finishing. In order to make the dish complete and substantial a few small suet dumplings should be well boiled and put into the tureen.
 
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