According to Liebig 34 lb. of beef should yield 1 lb. of extract, which should contain extractives 56-60 per cent, salts 18-24 per cent and water. It should be practically free from fat, protein and gelatin. Gelatin is sometimes added. It would be a valuable food if the extractives were tissue builders, energy producers or stimulants. As energy producers they are practically valueless, though some undergo further oxidation. They are certainly not tissue builders, and they are not true stimulants, either of the circulation or the nervous system. Modifications of Liebig's process were soon introduced, when it was recognized that the fluid had no nutritive value. Most of these modifications depend on the addition of some of the meat fibre which is previously separated. The meat fibre is in the form of insoluble protein. Although it is present in Bovril Fluid Beef and Bovril for Invalids to the extent of 8-9 per cent, the total percentage of protein and gelatin is, according to some analyses, less than that of fresh beef. The comparative analyses of dried meat, dried bovril and a yeast extract, called Marmite, must be noted, for the latter resembles meat extract and has been used in its adulteration.

Pro-toins.

Extractives.

Ash.

Water.

Organic Matter.

Reference.

Dried meat .

8670

780

5.3

54

94.6

oit

Dried Bovril.

4970

25.60

247

24.7

75.3

Voit

Marmite (1) .

410

4690

189

301

699

Hutchison

„ (2) . . .

10.50

3467

2695

26.84

7316

Makers

B. Meat Juices differ from meat extracts in that they are supposed to consist of the blood and fluid substances obtained by compression of the muscle fibres. Strong pressure is used to extract the juice which is subsequently concentrated by evaporation in vacuo. Heat must be avoided for it coagulates the protein. Hence the process is an expensive one and the product is liable to decomposition, unless preserved by the addition of glycerine, salt or some chemical preservative.

Many of these foods form a red solution on adding water, look like blood and are consequently repugnant. Some give the spectrum of haemoglobin. Bovinine appears to be a mixture of blood and glycerine, and gives the spectrum of methaemo-globin. There is considerable doubt as to the absorbability and nutritive value of haemoglobin. Puro depends for its nutritive value on egg albumin. If such a food is required, it is simpler and cheaper to take the white of egg and flavour with meat extract or home made beef tea. Valentine's Meat Juice is the most expensive and, according to Chittenden's analysis, the least nutritious of these foods on the market.

The composition of the various meat juices is shown in the table of analyses. The nutritive value of each depends on the amount of protein and varies enormously.

The Approximate Composition Of Beef Juices

Water.

Proteins and

Gelatin

Extractives.

N-free Substances

Mineral Ash.

References and

Remarks.

Armour's Beef Juice.

74.10

8.30

9.54

[ -

7.51

Attfield

Armour's Soluble Beef

23.07

33.382

1344

6.75

13.27

-

Bovinine ....

81.09

13-98

3.40

1.02

Chittenden

78.42

13.32

0.55

6.01

1.60

Hehner

Bovril Beef Juice1

52.01

7.23

14.03

20.763

5.97

-

Brand's Meat Juice .

59.15

15.454

16.55

-

8.85

No chemical preservatives

Burgoyne's Meat Juice

49.51

13.005

8.10

-

14.20

Candy

Esco Beef Juice .

52 43

7.60

5.90

13.62

20.39

Tankard

Lipton's Fluid Beef .

42.91

22.138

18.70

-

16.26

Lancet, 1898

Liquor Carnis1

56.06

6.96

5.01

28.42

3.55

-

Puro.....

36.60

3033

1916

-

9.79

Leyden's Handbuch. Contains much egg albumin

Valentine's Beef

60.31

0.55

29.15

11.30

Chittenden

Juice

51.21

9.657

11.16

-

10.84

Candy

Vitalia Meat Juice .

66.50

21.00

6.00

-

6.50

Lancet, 1895

Wyeth's Meat Juice .

44.87

38.018

-

-

17.12

Lancet

1 Analysis given by manufacturers.

2 3205 soluble.

3 Carbohydrates.

4 5.28 coagulable.

5 3.71 coagulable. 6 6.87 coagulable.

7 0.53 coagulable.

8 Including extractives.

Other Preparations

Curtis's Meat Juice, prepared from fresh beef by the cold process and supplied in glass bottles, contains haemoglobin, 2 3 per cent of coagulable albumen, 6.54 per cent of mineral matter, and 63.53 per cent of water. Vinsip is made of blood, boric acid and a little alcohol, and contains 16 per cent of protein. Alcoholic compounds of meat extracts must be severely condemned, even if enriched by addition of maltose or other sugars. They are very apt to set up the alcoholic habit.

Fresh meat juice is cheaper than these preparations and more valuable by reason of its freshness and its composition. From broiled rump steak, slowly pressed, a fluid can be obtained which contains from 5-7 per cent of protein. It contains a relatively small quantity of extractives, and can be given in considerable amounts without causing either diarrhoea or thirst. If the meat is minced, covered with about half its weight of water, allowed to stand for a few hours, and then squeezed through muslin, a fluid is obtained which contains from 2-4 per cent of protein. Meat juice can be given mixed with beef tea or in a coloured glass to hide the colour. The proprietary meat juices should be supplied in glass bottles or porcelain jars, and not in tins, for some of the tin may be dissolved out and cause symptoms of poisoning.

C. Predigested meat foods are generally sold under the name of peptones, fluid meat, or peptonoids. They usually contain more albumoses than peptones. The value of predigestion, partial or entire, has already been referred to. In the case of meat foods one great disadvantage is the tendency to induce diarrhoea, due to the albumoses and peptones. The amount of soluble protein varies greatly in the different foods, from only 3 per cent in Armour's Wine of Peptone to 80 per cent in Somatose. The next table gives the composition of these foods.

The Approximate Composition Of Peptone Preparations

Water.

Insoluble Pro-teins.

Peptones.

Albumoses.

Extractives and other Substances

Mineral Ash.

References.

Antweiler's Peptone

6.92

3.22

60.15

14.54

1.74

13.31

Konig

Armour's Wine of Peptone

83.00

-

3.00

12.90

1.10

Hutchison

Benger's Peptonized Beef Jelly

89.68

-

4.75

2.41

2.27

0.89

Konig

Brand's Beef Peptone

84.60

-

7.00

-

1.40

Hutchison

Carnrick's Liquid Peptonoids

5.40

24.00

65.40

[sugar chiefly)

5.20

-

Carnrick's Peptonoids

213

12.22

0.88

317

77.03

4.57

-

Darby's Fluid Meat

2571

-

30.60

-

30.18

13.50

Leyden's Hand-buch ; Konig ; Horton Smith, Journal of Physiol., 1891

Denaeyer's Peptone

78.45

-

12.15

4.32

2.54

Leyden's Hand-bitch and Von Noorden

Fairchild's Panopepton

81.00

-

3.00

15.00 (sugar chiefly)

1.00

Hutchison

Kemmerich's Meat Peptone

33.30

M0

3257

14.56

10.27

773

Konig

Koch's Meat Peptone

40.16

142

18.83

15.95

16.75

6.89

Konig

Liebig's Peptone

31.90

-

33.40

24.60

9.90

Leyden's Hand-buch

Mosquera Beef Meal

-

48.00

29.00

13.00 (Fat)

-

-

Savory & Moore's Fluid Beef

27.01

-

2.74

542

52.73

12.10

Konig

Somatose

14.25

_

62.25

2.62

5-30

Tankard

9.20

-

80.00

-

6.70

Valentine's Meat Juice

59.07

4.87

1.81

2273

11.52

-

Other peptone preparations may be mentioned : Gerrard's Liquid Peptone : a predigested protein and carbo-hydrate mixture, made from whole meat, malt peptone and detannated wine. Leube-Rosenthal Meat Solution : a preparation of meat which has been partially digested by hydrochloric acid, pounded up in a mortar, neutralized by alkali, and mixed with water to the consistency of a thin paste. It looks and tastes like salt cooked meat. Containing albumin 11.0 per cent, peptone 6.5, and fat 6.0, it is nearly as nutritious as and is more digestible than ordinary meat. Ju-Vis : a mixture of vegetables and meat extract. Its composition is given as water, 28.8; albumin, 1.10; peptone, 4.76; albumose, 9.92; nitrogenous bases, 20.63; non-nitrogenous matter, 9.37; mineral ash, 25.42. Ju-Vis Tablets are composed of extract of meat, gelatin, and Ju-Vis extract. One is sufficient to make a cup of beef tea, obviously of small nutritive value. Sanose : a preparation of casein 80 per cent and albumose 20 per cent, from white of egg. Brand's peptone preparations are made from beef, mutton, veal and chicken. Carnrick's Liquid Pep-tonoids are made from beef, wheat and milk. The manufacturers have recently stated that the total protein amounts to 6.89 per cent, of which 4.62 per cent is pure peptone. Their peptonoids contain meat bases, 2.87; fat, 2.00; lactose, 48.52; and starch, 23.64. The Mosquera Beef Meal is a meat which is partially digested by the ferment of pine-apple juice. Savory and Moore's Fluid Beef contains little peptone. Ordinary peptonized milk yields about 1.75 per cent of peptone, a sufficient amount for clinical purposes. Somatose is a grey powder, made from meat, soluble in water and almost devoid of taste and smell. A milk somatose is made from milk, with the addition of 5 per cent tannic acid; dose one to four drachms daily. Apart from the liability to cause diarrhoea, the possible weakening of the digestive functions from disuse, and the cost, these foods are unnecessary. If simple proteins, such as white of egg, dried casein foods, fresh meat or dried meat powders cannot be digested, then recourse may be had to the various forms of predigested foods which can be made at home from fresh food-stuffs, by the aid of peptonizing powders and pancreatic extracts.

D. Dried meat powders can be made at home by mincing cold boiled beef, drying it thoroughly in a slow oven, and grinding it up in a coffee-mill. Or it can be bought in the form of Meatox, Brand's Nutrient Powder, or a powder made by M'Call of London, containing 12 per cent of moisture and flavoured with salt and pepper. The composition of Meatox is : water, 5.0; proteins, 73.8; fat, 12.1; extractives, 7.7; salts, 2.0. It is a powdered beef, without preservatives. Meat powders can be added to other foods. Egg albumin is usually better. Dried casein foods are cheaper and purin-free. Powdered pulses are rich in protein.

Meat lozenges, beef tea tabloids, and combinations of meat extracts with other food-stuffs are to be absolutely condemned. Such lozenges and tabloids are quite innutritious and are practically concentrated salts and extractives.

(2) Fish foods are not plentiful. Marvis is a dried fish powder, made in Greenock N.B. from white fish, and mainly protein.

(3) Vegetable protein is sold in the form of Aleurone, a colourless, odourless, tasteless, fairly soluble powder, from the protein of wheat; or as Aleuronat, a yellowish-brown powder, almost insoluble in water, containing 80-90 per cent of protein. Legumin, or vegetable casein, is made from pulses; Plantose, from rape seed; and Roborat from cereals. Roborat contains 83 per cent plantose, is tasteless, the most soluble and the best. Marmite, Falona and Nutroa have already been referred to.

(4) Tropon is derived from waste vegetable and animal food» chiefly from fish and cheap vegetables. It is not very soluble and has a rather sandy taste. Vegox is a compound of essence of beef and vegetables, containing water 42.8, extractives 49.4, fibre and vegetable matter 7.8 (Hutchison).