A distinguished authority on dietetics long ago pointed out that a large proportion of our town population would profit by exchanging some of their meat as an article of diet daily for fish. There is no doubt that without exercise in the open air the digestive system is apt to become overloaded and oppressed by meals consisting chiefly of meat, and even if, as often happens, the primary digestion of the meat is, in the circumstances, fairly accomplished, many constitutions suffer from an over-supply of nutritive material which cannot be disposed of easily without considerable habitual muscular energy. In comparison with meat, fish is characterised by an alteration in the relative proportion of nitrogenous constituents, fish containing more gelatine and a smaller amount of extractives than meat. The proportion of water in the heavier varieties of fish is, moreover, much greater than in lean meat.

The special value of fish as an article of diet thus lies in the fact that it contains, in smaller proportion than meat, those materials which, taken abundantly, demand much physical labour for their complete combustion. The moderate amount of flesh-forming material present in fish, and in a form which entails little labour on the digestive organs - for most persons certainly less than meat - render fish a particularly valuable article of diet. The smaller amount of extractives present in fish is in one respect no disadvantage, since this diminishes the tendency to indulge in excess. Its greater richness in gelatine-yielding substances causes fish to lose more in boiling than meat does, and on this account boiled fish is an insipid and unattractive article of diet. The cheapest fish are cod, ling, herring, mackerel, and sprats, the cost of course varying with the supply.

Fish as a foodstuff contains a large proportion of water, a varying amount of fat and protein. The latter belongs chiefly to the gelatine-forming order. Isinglass, the finest form of gelatine, is obtained from fish bones, but more especially from cartilaginous fish, like the skate and sturgeon. According to the proportion of protein and fat in fish, they may be divided into two groups of "fat" and "lean".

Fish with more than 5 per cent, of fat - eel, salmon, turbot, herring.

Fish with from 2 to 5 per cent, of fat - halibut, mackerel, mullet.

Fish with less than 2 per cent, of fat - cod, whiting, haddock.

Fish are .it their besl just before spawning, when they are said to be in season (see table); later they become poor and flabby.

Fish In Season

Jan.

Feb

Mar

Apr.

May

June.

July.

Aug.

Sept.

Oct.

Nov.

Dec.

Bloater .

+

+

+

..

..

..

..

..

+

+

+

+

Cod.

+

+

+

..

..

..

..

...

. . .

+

+

+

Crab

..

...

+

+

+

+

+

+

..

. . .

. . .

Flounder.

. ...

+

+

+

+

+

+

+

...

Haddock .

+

.. •

..

..

+

+

+

+

+

Halibut .

+

+

+

..

...

• • •

...

+

+

+

Herring .

...

...

...

+

+

+

+

+

+

+

+

Ling

+

+

+

+

. • .

..

... .

+

+

Lobster .

+

+

+

+

+

+

+

+

+

+

. . .

. . .

Mackerel.

+

+

+

+

+

+

. . .

. .

+

+

+

Oysters .

+

+

+

+

...

...

...

...

+

+

+

+

Plaice

+

+

+

+

...

...

...

+

+

+

+

Salmon .

..

+

+

+

+

+

+

+

+

..

Skate

+

+

+

+

...

...

...

. .

..

+

+

Smelts

+

+

+

+

..

..

..

..

..

+

+

+

Sole.

+

+

. .

+

+

+

+

+

+

+

+

Trout

+

+

+

+

+

+

+

...

. . .

..

Turbot

+

+

+

+

. . .

.. .

+

+

+

. . •

Whitebait

+

+

+

+

+

+

+

. . .

• ••

. • •

• ••

Whiting .

+

+

+

+

..

...

...

+

+

+

+

...

Fish decompose readily, and cannot be cooked too fresh. The perfection of fish-cooking is obtained when the fish is transferred immediately from the water to the pot. Keeping in ice deteriorates the flavour. Skate and sturgeon are exceptions; they improve by being " hung," the muscular fibre becoming softer. Smoked, salted, and pickled fish are much less digestible than when fresh, and in this form they are better avoided by dyspeptics. The fish best suited for smoking are firm, oily fish, like the salmon and herring.

In selecting fish, the following are the main indications of freshness: - The flesh is stiff and firm, the animal being in a state of rigor mortis; the skin should be well covered with scales, and there should be no disagreeable smell. A most important point is that the eyes and gills are bright, while the tail is firm and not drooping. Cod, haddock, and whiting keep best, then flat fish; mackerel and herrings very rapidly get soft.

Varieties

The edible fishes fall into two groups - "white" and "oily" - the difference being whether they have the fat stored in the liver or distributed throughout the body.

The white fishes are the most digestible; they comprise the whiting, haddock, cod, brill, sole, plaice, flounder.

The following analysis of the flesh of cooked fish may be taken to represent approximately their average composition: -

Analysis Of Flesh Of Cooked Fish

Water in Flesh.

Reducing Substances in Dry Matter as Glucose.

Ash in Dry

Substance.

Solids in Dry Substance.

Nitrogen.

Fat.

Protein.

Brill ...

6274

4.42

15.49

1.62

93.9

Cod ...

76.32

6.67

3.31

I5.30

1.15

91.5

„ (salt) ...

72.35

7.14

14.26

12.41

0.94

76.0

Eels....

61.08

8.91

2.11

7.36

44.68

42.8

Gurnet . ...

73.77

14.77

3.53

14.24

i.81

89.1

Haddock..

72.37

13.15

3.28

13.11

1.29

79.5

Hake ...

84.88

13.64

3.90

12.86

5.67

81.3

Halibut...

74.46

...

4.11

13.32

15.81

79.6

Herrings..

6054

• • •

5.56

11.11

25.25

67.0

(salt) .

46.03

17.59

19.69

7.12

21.90

38.8

John Dory

77.89

14.29

2.06

13.32

8.52

79.5

Lemon Soles.

78.11

14.80

4.42

11.04

12.96

69.8

Mackerel..

73.13

13.93

407

10.46

25.73

62.3

Oysters . .

77.71

18.32

I2.l6

11.85

7.77

65.4

Plaice .

76.86

11.56

4.06

13.02

9.84

75.1

Red Mullet .

68.26

9.79

543

11.59

24.52

66.2

Roach .

75.37

6.28

1.08

13.03

15.03

79.1

Salmon . .

65.32

14.89

4.94

10.70

29.43

56.6

Sardines .

44.35

12.03

8.54

33.49

55.4

Smelts . . .

80.73

2.17

4.73

11.61

9.76

82.0

Soles . .

79.20

11.87

3.47

14.00

1.71

86.0

Sprats . .

75.77

0.88

6.42

9.26

27.37

57.9

Trout . .

73.58

4.68

6.60

11.96

8.81

80.0

Tunny . ...

63.49

5.52

10.55

30.68

66.0

Turbot . ...

77.84

11.81

2.41

13.76

4.75

84.7

Whiting..

78.78

17.54

1.92

13.28

1.86

79.5

The Whiting has been termed "the chicken of the sea." It is very light, easily digested, and when fresh possesses a very delicate flavour.

Haddock, when fresh, possesses a very delicate flavour; the flesh is firmer and harder than whiting. It is best to select one of medium size; when large, their flesh is coarse. Smoked haddocks are very well known, and vary greatly in digestibility. The small sort, known as the "Aberdeen findon," are quite tender; they are smoked with peat smoke. The Arbroath smokies are also easily digested. The larger forms, smoked with petroleum, are tough, and have not nearly so hue a flavour.

Cod is the toughest of the white fish. Its quality varies at the different seasons; sometimes the flesh is hard and full of fibre. In selecting cod a plump one of medium size, the head and tail small in proportion, and the sides looking as if the ribs were in the flesh, should be selected. The tail portion is the most tender, but has least flavour.

Ling

A cheap fish, not unlike cod; rather tasteless; requires a good sauce.

Trout

A fresh-water fish. The body has a silver and golden appearance when fresh. Those weighing about one pound are best. When in condition have excellent flavour, and very digestible.

Smelts

A very small fish, but much esteemed. When fresh, have a silvery hue.

Whitebait

A very small fish, of silvery appearance. Highly esteemed. Must be used quite fresh. Best in May, June, and July.

John Dory

The flesh is rather tough, and it is the better of being kept a day or two before being cooked. It is an unsightly fish, but of good flavour. It is best baked.

The flat fishes form another section of the white fishes, and comprise:

Sole

Very delicate, and easily digested. It is a fish of excellent quality. Medium size is best.

Plaice And Flounders

Flat fish of rather poor quality and flavour, easily digested. Moderate price. Choose one with a thick,firm body. They are best boiled,fried, or baked augratin.

Skate

Tough. A very decided flavour; improves with keeping for a day or two. The flesh should be firm and creamy in appearance. It requires to be skinned; unwholesome when out of season.

Brill

Like turbot in appearance, and much cheaper. When fresh, the flesh should be of a yellowish tint; if blue, it is not good. It is generally boiled.

Halibut

A flat fish, like turbot in appearance. Its flesh is very wholesome, and of excellent flavour. A middle cut of this fish is the best.

The oily fishes comprise:

Turbot

The best of all flat fish. The flesh is firm, rich, and white. The thick part of the fins is especially favoured by the epicure. A middle-sized fish is the best. This fish improves by keeping for a day.

Lobster

The lobster is more digestible than the crab; the flesh of the claws is better than that of the tail. It decomposes rapidly, and therefore is best bought alive. The bright red part within the body is the ovary; their spawn is very nutritious, and is often used in sauces for the sake of its flavour and colour.

Crab is inferior to lobster; the flesh is tougher and more indigestible. The medium-sized ones are best. Choose a heavy one, for if light it is watery. The male crab is best for table, and may be distinguished by the large claws.