Summary of the results of analyses made in the laboratory of the U. S. Department of Agriculture.

Number of samples examined.

Character of samples.

Number of samples containing- large additions of starch or flour.

Number of samples containing large amounts of cocoa husks.

Samples containing sugar.

Number containing 25 to 40 per cent.

Number containing 40 to 50 per cent.

Number containing 50 to 60 per cent.

Number containing 60 to 72 per cent.

6

Plain choclate................................................

4

..........

..........

..........

..........

...........

30

Sweet chocolate.............................

11

8

..........

..........

22

8

28

Cocoas, bromas, etc.........................

12

6

7

1

3

...........

64

Total.................................

27

14

7

1

25

8

Determinations made to show the solubility of cocoa and certain of its constituents in water.

Consecutive number.

Serial number.

Total ash.

In the air-dry sample.

Number of parts of ash in the water-soluble portion, per 100 parts of ash.

Number of parts of P205 in the water-soluble portion, per 100 parts P2O5.

Total

P2O5.

Total matter soluble in water.

Portion soluble in water contains -

Ash.

P2O5.

Per cent.

Per cent.

Per cent.

Per cent.

Per cent.

38

C899

5.05

............

18.27

3.87

1.27

77

.................

10

G893

8.64

1.99

19.84

5.77

1.02

67

51

42

6901

8.48

1.71

.................

.................

0.87

................

51

43

8889

3.17

0.94

11.28

2.70

0.80

85

85

51

8909

6.06

1.72

17. 92

2.27

1.27

37

74

53

8913

6.95

1.94

19.17

4.21

0.77

61

40

64

10485

7.89

.................

19.76

5.36

0.95

68

.................

Before proceeding with a discussion of the results obtained in this laboratory, a brief review of the methods proposed by various analysts for the judgment of samples and the interpretation of analyses is not considered out of place.

The Association of Swiss Analytical Chemists' regards the following determinations as absolutely necessary:

(a) Microscopical examination for foreign starches, cocoa husks, flour, etc.

(b) Quantitative estimation of moisture (in cocoa powder), ash, fat, sugar (in chocolate), and fiber.

(c) Taste, odor, and color of the aqueous infusion, as well as the appearance of the surface of fracture in cake chocolate and cacao-masse.

It is sometimes of value to determine (a) Quantitatively: Theobromine, tannic acid, and starch.

(b) Qualitatively: Fat and ash (for alkaline carbonates, mineral pigments, etc.). Not more than 2 per cent of alkaline carbonates in soluble cocoas is considered allowable by this association. The ash in normal samples of cacao-masse may vary from 2 to 5 per cent; the fat, from 48 to 54.5 per cent.

1 Op. cit., note 3, p. 949 of this work.

Mansfield1 states the average amount of starch to be 5 per cent in chocolate and 10 per cent in cocoa. He also gives the maximum amount of cellulose as 2.5 per cent for chocolate and 5 per cent for cocoa.

Bensemann2 proposes the determination of water-insoluble organic matter (=U), fat (= F) and starch (=S), as a means of judging the percentage of cocoa and flour in chocolate. He calculates these percentages from S and the coefficient S / U-F which he calls the starch coefficient.

The following results were obtained by Bensemann:3

I.

11.

III.

IV.

V.

VI.

Per cent insoluble organic bodies dried at 100 to 110° c,=U.........................................

69.0

35.5

36.0

37.0

37.0

30.0

Per cent fat, extracted with ether, dried at 100 to 110°, = F...........................................

28.0

22.5

21.0

17.5

19.0

6.5

Per cent starch, estimated as starch sugar by amount CuO, =S...........................................

13.0

4.5

8.5

12.0

11.5

17.0

Starch coefficient, = S/U-F...................................

0.317

0.346

0.567

0. 615

0.639

0.723

I. Was so-called soluble Dutch cacao.

II. Table chocolate (about 60 parts sugar, 40 parts cacao).

III. Crumb chocolate (about 60 parts sugar, 25 parts cacao, and 15 parts flour).

IV and V. Table chocolate (about 60 parts sugar, 20 parts cacao, and 20 parts flour). VI. Chocolate flour (about 60 parts sugar, 10 parts cacao, and 30 parts flour).

Filsinger4 makes the following recommendations:

Quantitative determination of ash (qualitative examination, if ash runs above 5 per cent in cocoa and 2.5 to 3 per cent in chocolate), fat and sugar. The fat is also examined qualitatively. The microscopic examination is considered very important.

Herbst5 determines in chocolate: Moisture, fat (quantitatively and qualitatively), ash, and sugar; and makes a microscopical examination. The ash should not exceed 2 per cent.

The following is abridged from Bernhardt:6

In many cases chocolates, to which a largo amount of flour and starch has been added, must be colored. The author found a Spanish chocolate, which contained 3.2 per cent ash, to be colored with 1.5 per cent ocher. As these additions are only assimilated by the chocolate in proportion to the amount of fat present, the addition of coloring matter necessitates the adulteration with foreign fats, so that we may obtain a chocolate that contains no cocoa whatever. The author has in reality found chocolates which consisted of cocoa-remnants, fat, sugar, spices, and coloring matter.

As cocoa butter is quite expensive, other fats are often added, and this writer there-fore considers the examination of the fat as the most important test. The following fats are mostly used as substitutes; cocoanut butter, rasped cocoanut. hazelnuts, almonds, animal fats, margarin, cotton and sesame oils, etc.

1Op.cit., note 1, p.950 of this work. 2 Rep. f. anal, chem., 1883,119. 3See also tables on pp. 967 and 968. 4 Op. cit., note 7, p. 938 of this work. 5Op. cit., note 4, p. 950 of this work. 6Z.Nahruiigsin. Hyg., 1890,4, 121.

Vanilla and vanillin are often replaced by balsam Pern, storax, tolu, and gum benzoin.

The melting and congealing points of the fats and of the free fatty acids are no indication whatever, as pure cocoa butter shows great variations.

Legler1 regards the cellulose determination as an uncertain means of detecting husks, because the results vary with the method used.