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FOODS:
THEIR COMPOSITION AND ANALYSIS.
TniUD Edition. In large 8vo. Cloth, with Tables and Illustrations. Price 21b.
POISONS: Thci*- Effects and Detection.
By A. WYNTBB BLYTH, M.B.C.S., P.C.S., Barrister-at-Law, Public Analyst for the County of Devon, ifcc. " Undoubtedly THE MOST complete work o;i Toxicology in our language."— '/Ae Analyst (on the Third Edition). , ,
" As a PRACTICAL GUIDE, we know NO BETTER work. -r-The Lancet (on the Third Edition).
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" The elegant dress of the little volume before us is but ths outer covering of a TRULY RICH KERNEL, and justly merits the praise it spontaneously calls forth. . . . Compact, handy, comprehensive, it certainly merits a high place among the text- books of the dnj."— Sanitary Record.
DISINFECTION and DISINFECTANTS. With an Account of the • Chemical Substances used as Antiseptics and Preservath^es. By Sajfuel RtDBAL, D.Sc. (Lond.), F.I.C., F.C.S., Examiner in Chemistry to the Royal College of Physi- cians. With Diagrams of the most approved Modern Appliances. 128. 6d. " Dr BiDEAL'S volume is bound to prove of great value."— P^iarTnacewt. Journal. "An EXHAUSTrra Treatise dealing with the whole range of the subject :— Disin- fection by Heat, Chemical Disinfectants, Practical Methods, Personal Disinfection, Legal Regulations, and Methods of Analysis ... so very well done and so USEFUL that it will be valued by all connected with Sanitation and iPublic Health. —Chemist and Drvggist.
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FAIRBANK'S O L E O-ST E A R I N E x65.
MICROSCOPICAL CHARACTERS OF LARD AND BEEF
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}■ fnntispictc.-
FOODS:
THEIE COMPOSITION ANB ANALYSIS.
A MANUAL FOR THE USE OF ANALYTICAL CHEMISTS AND OTHERS.
WITH AN INTRODUCTORY ESSAY ON THE HISTORY OF ADUL TERA TION.
BY
ALEXANDER WYNTER / BLYTH.
M.R.C.S., F.I.C., F.C.S., &ct ^
BAKRISTEK AT LAW ; PUBLIC ANALYST FOR THE COUNTY OF DEVON, AND MEDICAL OFFICEK. OF HEALTH AND PUBLIC ANALYST FOR ST. MAIIYLEBONE.
With Numerous Tables and Illustrations.
FOURTH EDITION, REVISED AND ENLARGED.
LONDON:
CHARLES GRIFFIN AND COMPANY, LIMITED j EXETER STREET, STRAND. 1896.
UNlVEREiTY lf UID*
I f V n ^ fl, ,vr c-r r^i f) ; 3
PEEFACE TO THE FOUETH EDITION.
The progress of analytical chemistry as applied to the investiga- tion of Foods has made such rapid strides since the previous edition of the present work, that the author has had consider- able difficulty in revising the pages so as to embody all that is of value, and, at the same time, retain the handy size of the older edition.
Processes which experience has shown to be faulty or imper- fect, have been omitted and replaced by new matter, and greater attention has been paid to the application of purely physical methods.
A number of new diagrams and new tables have been added. The author believes that the .work in its present form not only embodies the results of his own personal experience, but fairly represents the views and details the methods of the modern Food-analyst.
The Court House,
St. Marylebone, W.,
February, 1896.
PREFACE TO THE SECOND EDITION.
The following pages are an instalment of the Second Edition of the Author's ''Manual of Practical Chemistry''' — the JFirst Part of the New Edition being now issued separately under the title of ''Foods: their Composition and Analysis,'' and the Second Part under that of " Poisons : their Effects and Detection." The reasons for the alteration of the title are sufficient!)^ ob- vious : the present appellation is distinctive, rendering impos- sible any confusion between this Manual and others (of a widely different scope and manner of treatment) which might come equally under the designation, "Practical Chemistry."
The present Volume, however, is not a mere reprint of the Division, " Foods" in the First Edition. It has been thoroughly revised and re-written, where necessary, and enlarged by the addition of new matter to more than double the number of pages allotted to the subject in the original work.
The Historical Introduction prefixed is the result of consider- able labour and research, and, it is hoped, will be found — together with the review of English Legislation, Past and Present, relative to Adulteration — not without interest. As in the First Edition, abstracts of a few legal cases are given at the end of the chief Articles. These have been carefully selected, as illustrative either of ingenious defence, or of certain points in the Adulteration Acts. It has often been remarked that private individuals rarely avail themselves of the " Sale of Food and Drugs " Act. This, probably, is due to insufficient acquaintance with the technical details of the mode of proce- dure, and the Author has, therefore, been careful to explain the " Purchase " sections fully in their relations both to the official Inspector and to the private purchaser. In the Appendix will be found the Text, entire, of the English laws at present ia
viii PREFACE.
operation, as well as tlie best and most recent of the American Acts relating to the Adulteration of Food.
In the Scientific Portion of the work, the professional Chemist wm find details of most of the processes of any value in Food Analysis hitherto published, and in all cases (either by the aid of Footnotes, or in the Bibliography appended to each Ai^icle) the original source of the information is indicated. In addition, are given a large number of Processes, either invented or im- proved by the Author, and not previously published— such, e.g., as those described in the Articles on Milk, Butter, Tea, Flour, "Wtxtcr (fee.
Numerous Tables, some of which are indispensable and others convenient, have also been added ; and new Illustrations, from original drawings, introduced.
The Article on Milk— 2. special feature of the First Edition- is still farther enlarged, and contains the Author's most recent researches on the subject. It may, perhaps, be considered a fairly complete Monograph. In the Article on Water (added by request) the application of an improved process for combustion in a vacuum is detailed, and the importance of Biological methods of examination is insisted upon— not as supplementary to Chemical tests, but as of equal (if not of superior) value to
Though the scope of the Manual is mainly that of a Labora- tory Handbook, yet the dietetic and medical aspects of the more important Foods are, where necessary, fully considered, and the Author believes that a great proportion of the work is thus of that general interest which will render it useful to those who, without much chemical knowledge, yet desire to have, in a form admitting of easy reference, the latest information relative to Foods and Beverages.
In conclusion, he can only express a hope that the work, m its new shape, will be found widely useful, and more worthy of the very kind reception accorded to the First Edition.
OouBT House, St. Mabylbbons, April, 1883.
CONTENTS.
PART I.— HISTORY OF ADULTERATION,
I. EARLY NOTICES OF ADULTERATION, ESPECIALLY IN ENGLAND.
Section _ Page
1. Roman and Greek Notices of Adulteration, .... 3
2. Low Standard of Commercial Morality in the Eleventh, and
Twelfth Centuries, 5
Assizes of Bread — Bakers.
3. Early Regulations in England relative to the Assize of Bread, . 5
Statute of Assize, 1582, &
Frauds of the Bakers 7
Brewers and Vintners.
4. Beer, 8-
Fraudulent Practices of early Brewers, Ale-tasters, ... 9
5. Wine, 9
Spices— Drugs.
6. Regulations of the Pepperers, 10"
Regulations of the Druggists and Grocers, . . . . 11
n. adulteration in France.
7. General Inspection of Provisions in Olden Time by the "Police
des Commissaires," and Ancient Regulations relative to
the Adulteration of Beer, 12
8. Flour and Bread — Various Decrees relative to, ... 12 Punishments of French Bakers by Penance, &c., ... 12
9. Wine— A Curious Decree of the Provost of Paris, ... 13 Inspectors of Wines and Drinks appointed, .... 13
Poisonous Wine, 13
" Vin lie Raisin de Bois," 14
10. Butter— Regulations relative to the Sale of, ... . 14
11. Drugs, 14
12. Conseils de Salubrite', 15-
X
CONTENTS.
III. ADULTEBATION IN GERMANY.
Section
13. The Old German Guilds,
14. Old German Regulations relating to Bread, .... ■IK Wine, . . . •
" Drugs— Establishment of
ID. >> . °
the Continental Pharmacopceias
IV. HISTORY OF ENGLISH LEGISLATION WITH REGARD TO THE ADULTERATION OF FOOD.
17. First General Food Act, 1860
18. Bakers— Bread,
19. Acts relating to Beer and Porter, ....
20. „ Wines,
21. The Tea Acts, • \ • * ^
22. The Coffee Acts— History of Regulations as to Chicory una
Coifee,
23. The Select Committee, 1855, :„ The Analytical Sanitary Commission of the Lancet,
24. The Adulteration Acts, 1860 and 1872, .
25. The Select Committee, 1874, . -.^ * '
26. The Sale of Food and Drugs Acts, 18/5 and Ib/y, .
The " Prejudice " question,
Sale of Food and Drugs Act, 1879, ....
Pago 15 IG 16
18
18 19 20 20 21
21-24 24 25
26-28 28 29 29 31
HISTORY OP THE PRESENT SCIENTIFIC PROCESSES FOR THE DETECTION
OF ADULTERATION.
32 32 32
27. Early Workers
28. Discovery of Milk-sugar by Bartoletus,
The Experiments of Francesco Redi, &c., ^ • ' , '
29. The Works of the Hon. Robert Boyle, and of J. B. Vauden
Sande,
30. The Invention of the Microscope. . • ^- • • Antony Van Leeuweuhoek, Dr. Hy. Power, Ehrenberg, Donne,
31. General Advance of Chemistry : Neumann Caspar, Loerhaave,
Berzelius, &c.,
32. Accum's work.— "Death in the Pot," • ■ ■ , -r, \ '
33 The Works on Adulteration of Food, &c. , by Bossy and Boutron-
Chavlard, Gamier and Harel, and Fnedrich, . .
34 The Works of John Mitchell, Chevallier, and Normandy,
35 Chevallier's Dictionary— Alphonse Normandy's Handbook, .
36 Dr. Hassall's Contributions to the " Lancet," . . 37*. The Establishment of the Society of Public Analysts,
The "Analvst" — "Limits," . • n ' 38. A list of General Treatises on Adulteration chronologically arranged,
VI THE PRESENT LAW IN ENGLAI.D RELATIVE TO ADULTERATION OF FOOD.
The Sale of Food and Drugs Act 38 and 39 Vict., c. 63, and Sale of Food and Drugs Act Amendment, 42 and 43 Vict., c. JO.
•^q Preamble of the Act ; Definition of " Food and Drup " . . 46 ?ie M^xinL ColourL^^ or Staining of Foods, and the Com- pounding of Drugs
33 34 34-37
37 37
40 41 41
42 42 43
43
co::rTENTS. xi
Section Page
40. The " Prejudice" question ia the Acts, 48
Regulations or Limits as to the Strength of Spirits, . . 49 Drugs to be sold only in Accordance -with the Demand of the
Purchaser — No Offence if there is a Label Distinctly de- scribing the Article sold — Abstraction from any Article of Food of any Constituent likely to impair its pi'operties, &c., 49
41. The Label Section — Appeal Case of Liddiard v. Keece, , . 49 The Question of Completeness of Sale, ..... 50
42. Question as to how far Notices over Shop Doors, &c., protect a
Vendor, 51
43. Appointment and Qualifications of Analysts, .... 52
44. The Purchase of Samples by a Purchaser for Analysis, . . 54
45. The Procuring of Samples for Analj^sis by Medical OfEcers of
Health, &c., 55
Penalty for Refusal to Sell— The Case of Rouch v. Hall, . . 55
46. Method to be pursued by a Purchaser under the Act, . . 56
47. Regulations of the General Post Office relative to the Trans-
mission of Samples through the Post, .... 58
48. The Certificate of the Analyst — The Institution of Proceediags — Quarterly Reports of the Analyst— The Certificate of
the Analyst is Evidence, 59, 60
49. Provision for Analysis of the Sample at Somerset House— The Defendant may Prove by Written Warranty that he had
no Reason to believe the Article sold was any other than
Pure, &c., 60
Provision for Payment of Penalties — The forging of Warranties — The giving of False Labels— The Proceeding by Indict- ment—The Examination of Tea on Importation, . . 61
VII. THE DUTY OF THE INSPECTOE OR PUECHASER TJKDER THE ACT.
50. Giving full details as to the Duties of an Inspector under the
Act, 62-64
PART II.— INTRODUCTORY.
I. DESCRIPTIOK OP A PEW SPECIAL POEMS OP APPARATUS TJSEFITL IN FOOD
ANALYSIS.
51. Soxhlet's Fat-extracting Apparatus with Various Modifications, 67 Wynter Blyth's Ether Tube and " Ether Recovery" Apparatus, 68, 69
52. The Spiral Balance, 70
53. Vacuum Processes— The Mercury Pump, .... 71
II. THE MICROSCOPE, THE SPECTROSCOPE, AND THE ART OF PHOTOGRAPHY
AS APPLIED TO THE CHEMISTRY OF FOOD.
54. The best Form of Microscope— Manipulation of Tissues, . . 72-74
55. Ihe Micro-spectroscope, 74
The Sor by-Browning Micro-spectroscope— Measurement of
Bands, 74-78
The Hema-spectroscope of M. de Thierry, '. '. * 78-79
xii
CONTENTS,
Section Pago
56. Spark Spectra — The method of L. de Boisbaudran, . . 79, 80 56a. The Tolarising Colorimeter — The Colorimeter with the
Lumner-Brodhuns Prism, . . . .' ... 80-84 56&. Quantitative Spectroscopy — Karl Vierordt's divided Slit — The Extinction Coefficient — The Absorption Spectrum of Permanganate, ........ 84-89
57. Photography — Stein's Photographic Microscope — Dr. Wood-
ward's Method, 90
58. Colour — Mr. Sorby's Method of Examining Colouring-Matters, 91,92
59. Red Colouring-Matters — Cochineal— Absorption Factors for Car-
minic Acid — Aniline Reds — Absorption Factors for Fuch- sine — Safranine — Coralline — Aurine — Ponceau — Congo Eed — Erythrosine — Fast Red — Biebrich Scarlet— Cioceine Scarlet — Alkanet — Madder — Alizarine — Purpurine — Safflower — Logwood — Effect of Alum on Logwood Spec- trum—Brasiline— San talin— The Red Colouring -Matters of Fruits and Berries, 92-100
60. Orange and Yellow Colouring-Matters— The Annatto Colours
— Turmeric— Picric Acid — Fustic— Chrysophanic Acid — Gamboge — Aniline Oranges and Yellows — Croceine Orange — Rosorcin Yellow — Diphenylamine Yellow — Diphenylamine Orange— Chrysoidine— Methyl Orange— Metanil Yellow— Phosphine, 100-103
61. Green Colouring -Matters— Chlorophyll Group of Colours— "
Aldehyde Green— Iodine Green— Malachite Green, . . 104-106
62. Indigos and Violets — Indigo— Indigotin— Litmus— Aniline
Blues— Methylene Blue— Aniline Blue— Methyl Violet- Alkali Blue, 106-108
63. Brown Colours— Bismarck Brown-— Acid Brown— Caramel, . 108, 109
64. Scheme for the Detection of the Aniline and other Colouring-
Matters by Chemical Reagents, 109-113
64a. Witt and Weingartner's Classification of Aniline Colours, - 113-117
The Mineral Matters or "Ash" of Food. Analysis of the Ash of Organic Substances.
65. The Percentage of Ash— Ash Soluble in Water— Ash Soluble
in Acid— Alkalinity of Ash— Percentage of Chlorine- Phosphoric Acid in the Ash, 117-119
66. General Method of Determining all the Constituents in an
Ash— Determination of Carbon Dioxide— Of Sulphuric and Phosphoric Acids— Bunge's Process for the Alkalies— Laucier's Method of Determining the Ash of Sugar, . 11 /-1-3 66a. Methods of Estimating Nitrogen and Nitrogenous Substances in Foods— Estimation of Total Nitrogen by Kjeldahls Method— Estimation of Nitrogen from Albumen— Esti- mation of non-Albuminoid Nitrogen— Estimation of Am- monia— Estimation of Amido-Acid and Amide Nitrogen, 123-12^
CONTENTS.
xiii
PART III. -CARBO-HYDRATES. Starchy and Saccharine Substances.'
Page
67. Classification of the Carbohydrates— I. The Grape Sugar
Group— II. The Cane Sugar Group— III. The Carbo- hydrates—Cane Sugar— Compounds of Inorganic Bases with Sugar 126-129
68. Adulterations of Sugar— The Detection of Dextrin— Of Starch
Sugar— Of Mineral Matters, 129-132
69. Full Analysis of Sugar— Methods of Taking the Ash of Sugar
— Laugier's Method, 132-135
70. Glucose or Grape Sugar— How to obtain it— Properties, . 135, 136
71. Levulose, 136
Estimation of Sugar.
72. Estimation of Sugar— 1. Chemical Processes depending on
the Precipitation of Copper Suboxide— 2. Volumetric Processes by Aid of Solutions of Salts of Mercury— Knapp's Solution — Sacchse's Solution, . . • . . . 137, 138
73. Soxhlet's Researches on the Behaviour of Invert, M ilk-Sugar,
• Galactose, and Maltose to Fehling's Solution — The Cyanide Copper Process — Dr. Pavy's Process— Physical Processes for the Determination of Sugar— MitscherUch's Polariscope— Soleil's Saccharimeter — Jellett's and other Polarimeters, 139-150
Confectionery — Sweetmeats.
74. Flavoiiring and Colouring-Matters of Sweetmeats — Composi-
tion of Sweetmeats, ........ 150, 151
75. Analysis of Sweetmeats, 151, 152
Honey.
76. General Description of Honey — Analyses of Honey — Characters
of Pure Honey — Adulterations of Honey — Artificial Honey, 153-157
Treacle — Molasses.
77. Composition and Analysis of Treacle, 157, 158
Jam and Preserved Fruits.
78. General Composition of Jam, 158, 159
79. Microscopical Structure of Apples, Pears, Damsons, Plums,
Oranges, and Lemons, the Strawberry, Raspberry, Goose- berry, Blackberry, and the Currant, . . . .159-162 Saccharin 163
Starch.
*
80. Starch, its Composition— Method of Estimation, . . . 163-169 Microscopical Identification of Starches, . . . . 170, 171 Division of Starches, 171-176
Xlv CONTENTS,
Section p^^^
81. Vogel's Division of the Starches, 176, 177
Karmarsch and Wiesner's Values, 177, 178
Bibliography relative to the Starches, . , . . 178
Wheat — Wheaten Flour.
82. Varieties and Composition of Wheat, 179
S3. Constituents of Flour, 179-186
Analysis of Flour.
84. Microscopical Examination of Flour, 186
,, Structure of Corn-coclde, 187
Detection of Ergot in Flour, 189
,, Potato Starch, . . . . . . , 190
,, Leguminous Starches in Flour, .... 191
85. ,, Alum and Mineral Matters generally in Flour, . 193-196
86. Proximate Analysis of Flour, 196-198
87. Legal case relative to Flour, 198
Beead.
88. Definition of Bread — The Proce ss of Making Bread, . . 199 General Composition of Bread, ...... 199, 200
Alteration of Bread by Moulds. &c., 201, 202
89. Adulterations of Bread, 202
90. Alum in Bread — Its Influence on Health : Methods for its
Estimation, 203-207
Bibliography relative to Flour and Bread, .... 208, 209
91. Infants' Farinaceous Foods, 209, 210
Oats — Oatmeal.
92. Composition of the Oat — Oatmeal — Adulteration of Oatmeal, 210, 211
Barley.
93. Barley— Barley Bread, 212, 213
Rye.
94. Composition of Rye Flour— Rye Bread, 213, 214
Rice.
95. Composition of Rice— The Ash of Rice, 214, 215
Maize.
96. Composition of Maize— Ash of Maize, 216, 217
Millet.
97. Composition of Millet— Asli of Millet, 217
Potato.
98. Composition of the Potato — The Fungus Producmg the
Potato Disease— Analysis of the Potato,. . . . 218-221
CONTENTS.
XV
Peas.
Page
99 General Composition of Peas-Analysis of Peas, . . . 222-224 lOo'. Preserved Peas-Copper in Peas— Discussion as to Poisonous Effects of Coppered Peas,
Chinese Peas.
101. Composition of Chinese Peas, 227
Lentils.
102. Composition of Lentils, 22S
Beans.
103. Composition of the Kidney and the Broad Bean, . . . 228, 220
PART IV. -MILK, CREAM, BUTTER, CHEESE.
MILK.
Historical Introduction.
104. Early Ideas as to the Composition of Milk : Aristotle— Avi-
cenna—Placitus—Panthaleon—Bartoletus— Bartholomew Martin — Ludovico Testi — Leeuwenhoek, . . . 230, 231
105. Boerhaave's Views on Milk, 231-233
106. Early Quantitative Analyses of Geoffroy and Doorschodt, . 233, 234
107. The Experiments of VuUyanoz as to Milk-Sugar, ... 234
108. The Investigations of Voltelenus on Milk, .... 234, 235
109. The Experiments of Schoepff, Scheele, Hoffman, and Caspar
Neumann, 235, 23&
The Composition of Cow's Milk.
\10. The General Physical Properties of Milk, .... 236-238
111. The Amphioteric Reaction of Milk, 238
112. Total Solids of Milk, ........ 238, 239
113. Milk-Fat, . 239
114. Chemical and Physical Properties of Palmitin, Stearin, Olein,
and other Constituents of Milk-Fat, .... 239-242
115. The Albuminoids of Milk 242-245
116. Milk-Sugar, 245, 246
117. Mineral Constituents of Milk, 246, 247
118. Other Constituents of Milk — Lacto-Proteine, Galactin,
Lacto-chrome, 247, 248
119. Bitter Principles in Milk— Kreatinine 248, 249
120. Odorous Principle in Milk, . . . . . • • 249, 250
121. Summary of the General Constituents of Milk, . . . 250
xvi
CONTENTS.
Gases of Milk.
■Section Page
122. The Author's Investigation of the Gases of Milk, . . . 251-253
"Fore" Milk.
123. "Fore" Milk— Fractional Milking 253, 254
HuMAK Milk.
124. Composition of Human Milk, 255, 256
Milk of other Mammals : Lactescent Peoducts of Birds and
Plants.
125. Milk of the Ass, 256, 257
126. „ Goat, 257, 258
127. ,, Mare, 258
128. ,, Sheep, „ . . 259
129. „ Camel 259
130. ,, Llama, 259
131. ,, Hippopotamus, 259, 260
132. „ Sow, 260
133. Bitch, 260
134. „ Cat, 261
135. Milk-like Secretions of Birds and Plants, .... 261
Abnormal Milks.
136. Abnormal Lacteal Secretions of Men and Animals — General
Examination and Analysis of Milk, 263, 264
137. Classification of Processes for Milk Analysis, . . 264, 265
I. Microscopical and Biological Examination of Milk.
138. Microscopical Appearances of Milk — Bacteriology of Milk, . 265-267
II. Analytical Processes more particularly for the Purposes of the Food Analyst.
139. Early Processes of Milk Analysis, 267, 268
A. General Analysis of Milk.
140. Specific Gravity— Total Solids— Extraction of Milk -Fat-
Extraction of Milk-Sugar, Albuminoids, and Ash, . . 268, 269
B. Various Methods Proposed for Extracting the Milk-Fat. Solvents for Fat— Addition of Sand— Adams' Method— Esti- mation by Centrifugal Machines— Soxhlet's Process— The Werner-Schmidt Method of Fat Estimation, . . . 269-275
C. Various other Methods of Milk Analysis. 141 Drying in a Vacuum— Direct Determination of the Water- Absorption of the Water by Dehydrating Agents — llitthausen's Copper Process— Muller's Process— Claus- nizer and A. Mayer's Process— Summary, . . . 275-280
CONTENTS. XVU
III. Special Details as to the more Exhaustive and Scientific
Analysis of Milk.
Section , , , i
142. Analysis of the Milk-Fat and Examination of the Ethereal
Extract of Milk, 280, 281
14.3. Detection and Estimation of the Carbo-hydrates of Milk, . 281, 286
144. Estimation of the Ash of Milk, 286
145. „ Albumen, 287, 288
146. Isolation of Galactin— Estimation of the Total Nitrogen in
Milk, 288
147. Isolation of the Principles precipitated by Tannin, . . 288
148. Estimation of Urea, 289
149. „ Alcohol, 289, 290
150. „ the Volatile Acids, 290
151. „ the Total Acidity of Milk, . . . .290,291
152. Detection of Metals in Milk, 291, 292
Nitrates in Milk, ...... 292
The Milk Secreted by the Unhealthy.
153. The Chemical Characters of Diseased Milk are not markedly
different from Healthy Milk, 292, 293
I, HUMAN MILK.
154. Some Analyses of Human Milk derived from Persons in Ill-
Health, 293
II. cow's MILK.
155. Milk from Cows suffering from Aphthous Fever, Mammitis,
Parturient Apoplexy, Pneumonia, Engorgement of Rumen,
&c. , Phthisis, and Local Affections of the Udder, . . 294-298
156. Milk of Cows suffering from Typhus 298
157. The Propagation of Disease through Milk, .... 298 The Relation of Milk to Scarlatina 298-300
,, ,, Phthisis and Tubercular Maladies, . 300-303
The Communication of Aphthous Fever by Milk, . . . 303, 304 A new Form of Febrile Disease associated with Milk, . , 304, 305
Decomposition op Milk.
158. Lactic and other Fermentations of Milk— Tyrotoxicon, • . 305, 306
159. Blue Milk, 306, 307
Adulteration of Milk.
160. General View of the Adulterations of Milk, .... 307 Calculations relative to the Water in Milk, .... 308, 309
161. Method of Calculating the Removal of Cream— The Addition
of Cane-Sugar to Milk, 309-311
161a. The Adulteration of Fresh Milk with Condensed Milk, . 311
162. Mineral Adulterants of Milk— Boracic Acid or Borax in Milk
— Quantitative Estimation of Boric Acid— Formaldehyde in Milk— The Addition of Glycerin, Salicylic Acid, &c., 311-316
b
iviii
CONTENTS.
Preservation of Milk.
Section _ _ PftRo
163. The Principles of Preserving Milk, .... 317
164. Evaporating Processes, various Patents, .... 317, 318
165. The Preservation of Milk b}' various Additions, such as
Sugar, &c., 318, 319
166. Action of Cold on Milk, 319, :«0
167. Heating and then Cooling Milk, as a Method of Preservation, 320
Influence of Food our the Quality and Quantity of Milk.
168. The Experiments of Weiske, Dumas, Beusch, Boussingault,
Payen, Liebig, Fleischmann, and Struckmann on Feeding Animals, and the Influence of Food on the Produce of
Milk, 320-324
109. Contamination of the Milk by Poisonous Colouring or Bitter Principles consumed by the Cow — The Iniiuence of Pas- tures manured with Sewage 324, 325
170. Metals in Milk, 325, 326
The Quantity of Milk given by the Cow, the Method OF Feeding, &c.
171. The Capacity of the Udder for Milk 326
172. Relative Value of various Breeds of Cattle as Milk-Producers, 326, 327
173. The Feeding of Milking Cows, 327, 328
Cream.
174. Composition of Devonshire Cream, of Ordinary Cream, Arti-
ficial Cream, 328-330
Skim -Milk.
175. Composition of Skim-Milk, 331
Condensed Milk.
176. Composition of various Skim-Milks— Condensed Milks, . 331-333
Koumiss.
177. Preparation and Composition of Koumiss, .... 333
Legal Cases Relative to Milk.
178. Defence that Milk had been deprived of Cream by Uninten-
tional Skimming— The Manufacture of Condensed Milk — Novel Defence— Adulteration of Milk with Cane-Sugar and Water— Defence that the Milk was Watered by the Rain— Conviction for selling "Fore" Milk— Conviction
for selling Diseased Milk, 334-337
Bibliography relative to Milk, 337-339
Butter.
179. Constituents of Butter 340-341
Oleo-Margarine— Butterine.
180. Manufacture and Composition of Butterine, .... 341-343
,1..,^ «. ./viw^ic
CONTENTS.
XIX
Analysis anb Adultebation of Butter.
Section 181. 182. 183. 184.
The Adultercations and General Analysis of Butter,
Certain simple Tests,
Cohesion Figures— Empirical Tests for Butter, . Methods of taking the Melting-Point and Specific Gravity ot
Butter,
Disc Method of taking Melting Points, The Titer Test, . . • • • . , ^ ..
Application of the Refractometer to the Testing of Butter
Fat, • ^ •
The Oleo-Refractometer of MM. Amagat and Jean,
Specific Gravity,
The Viscometry of Butter,
185. Direct Titration of Butter-Fat by Koettstorfer's Method,
186. Decomposition of Butter-Fat into Fatty Acids and Glycerin
Reichert-Meissl's Process, , ' o i
The Process of Mr. West-Knight— Saponification by Sul
phuric Acid— Wm. Johnstone's Process— Further Analysis
of the Insoluble Fatty Acids, . The Estimation of Butyric Ether, . Estimation of Glycerin, ....
Hubl's Iodine Method,
The Cryoscopic Method of examining Butter-Fat,
Summary,
Legal Case relative to Butter, Bibliography relative to Butter, .
Page 343-34(> 346-348 348-350
351, 352 352-354 354
354-357 .358 359, 3R0 360 361, 362 362-364 365-367
367-370 371 371 372-374 374-376 376
376, 377
377, 378
Buttermilk. 187. Composition of Buttermilk, .
378
Cheese.
188. The Principles of the Manufacture of Cheese, . . . 379
189. Neufchatel Cheese— Fromage de Brie— English Cream Cheese
— Camembert— Roquefort Cheese— American, Cheddar, Dunlop, Gloucester, Stilton, Gruyere, Gorgonzola, Skim Cheeses, 379, 380
190. Parmesan Cheese, 381
191. The Ripening of Cheese, 381-3S3
192. Analysis of Cheese— Adulterations of Cheese, - . . 383
Arsenic in the Rind of Cheese, 385
Tyiotoxicon, ........*' 38d
Whey 385
Bibliography relative to Cheese, .... . . 3S6
Lard.
192a. Varieties of Lards, 386, 387
1926. Physical Characteristics of Lard, ..... 387
192c. Chemical Characteristics of Lard, ..... 3SS-390 192rf, Adulteration of Lard— Chemical Constants— Special Tests for Vegetable Oils— Detection of Beef Stearin— Larderine
—Bibliography, 390-394
CONTENTS.
PART v.— TEA, COFFEE, COCOA.
I. TEA.
Section p._»
193. Varieties of Tea, 395
194. Structure of the Tea Leaf ". '. ! 395, 396
195. Chemical Composition of Tea 397-400
Theine or Caffeine, Boheic Acid, Quercitannic Acid, Quercetin, 400, 401
Composition of Tea.
195. General Analysis of Tea— Konig's, Dragendorff 's, and Mulder's
Analyses of Tea— Preliminary Examination of Tea, . . 401-403
Microscopical Methods of Detecting Adulterations in Tea.
197. New Process for the Examination of Leaves and Vegetable
Tissues generally under the Microscope — Permanganate Process— Skeleton Ashes,
198. Chemical Method for Detection of Foreign Leaves in Tea —
The Detection of Facing,
403, 404 404-40G
Leaves Used, or Supposed to be Used, as Adulterants of Tea. 199. Micro-structure of the Beech Leaf, Hawthorn, Camellia
Sassanqua, Sloe, Ghloranthus Inconspicuus,
407-411
Chemical Analysis of Tea.
200. Hygroscopic Moisture of the Tea Leaf,
201. The Estimation of Theine or Caffeine,
202. Determination of Total Nitrogen, .
203. „ Tannin, .
204. The Extract of Tea,
205. The Ash of Tea, ....
206. Determination of Gum, .
207. General Review of the Adulterations of Tea,
208. Bohemian Tea,
Bibliography relative to Tea and Theine,
411, 412 412-414 414 415-418
418- 419
419- 422 422
422, 423
423, 424 424
Matk.
209. Manufacture, Description, and Analysis of Mat^— Analysis of Ilex Paraguayends,
425-427
IL COFFEE.
210. Description of the Coffee Berry — Microscopical Structure, . 428, 429
211. Cbemical Changes during Roasting, 429, 430
212. Constituents of Coffee, 4.30-433
213. Analysis of Coffee, 433-435
Adulterations of Coffee and their Detection.
214. The Adulteration of Coffee with Chicory — Its Detection —
Microscopical Detection of Adulterations in Coffee — Vegetable Ivory — Date Stones — Leguminous Seeds, . 435-440
CONTENTS.
xxi
Section
215. The Adulteration of Coffee with the Seeds of Cassia, . Composition and Analysis of " Date " Coffee,
216. Estimation of Chicory in CofiFee, .....
217. The Methods of Hiepe, Prunier, Hager, and others for detect
ing Adulterations in Coffee,
Bibliography relative to Coflfee,
Page 441 442 442-445
446 447, 448
III. COCOA ANB CHOCOLATE.
218. Microscopical Structure of the Seed, 448
219. Varieties of Cocoa, , . 459
220. Chocolate, 45O
221. Average Chemical Composition of Cocoa— Cocoa Butter—
Bjorklund's Test— Hager's Aniline Test, . . . .451, 452
222. Composition, Effects, and Estimation of Theobromin, . . 452-455 222a. Cocoa Bed— Zipperer's Method of Determining Cocoa Red
and the Products of its Decomposition, . \ . . 455-457 2226. Determination of Crude Fibre, 457
223. The Ash— Mineral Constituents of Cocoa— Bensemann's An-
00. ^^.alyses of Cocoa, 457-462
224. Nitrogenous Constituents of Cocoa, 463
225. Adulterations of Cocoa, [ * 453
226. Adulterations of Chocolate, ....... 464
Bibhography relative to Cocoa and Chocolate, . . ', 464, 465
PART VI.-ALCOHOL, SPIRITS, LIQUEURS, FERMENTED LIQUORS AND WINE.
ALCOHOL.
227. Alcohol— Ethylic Alcohol, .
228. Rectified Spirit— Proof Spirit, Specific Gravity Table, .
229. Tests for Alcohol, ....'.[
230. Separation of Alcohol from Animal Matters, '
. 466, 467 467 . 468-470 . 470-472 •. 472, 473
Estimation or Alcohol in Spirits and Alcoholic Liquids.
231. Various Methods for the Estimation of Alcohol— Methods
used in the Examination of Alcohols in the Municipal Laboratory, Paris, 473 475
232. Estimation of Alcohol by Distillation— Tabarie's Method-^
o-i'i AT ^V y^PO^™eter— Oxidation into Acetic Acid, . 476-479
233. Methylic Alcohol, Tests for, and Estimation of— Formic Acid
EtheJr*^ of Alcohols-Aldehydes-Furfurol— Acetone—
234. The Higher Alcohols, B'ardy's Method— Bases, '. 483-488
Brandy.
235. Composition and Adulterations of Brandy, .... 489
236. Composition and Analysis of Rum, 490, 491
xxii
CONTENTS.
Whisky.
Section Page
237. Composition and Adulteration of Whisky, . . . .491, 492
238. Effects of the Higher Alcohols, 492
239. Prosecutions for Adulterated Whisky, 492, 493
Gin.
240. Composition of Gin, 493
241. Oil of Calamus, 493
242. Oil of Cardamoms, 493, 494
243. Angelica Root and its Active Constituents, .... 494
244. Oil of Coriander, 494, 495
245. Oil of Juniper, 495
246. Analysis of Gin, 495, 496
Arrack.
247. Composition of Arrack 496, 497
LIQUEURS OR CORDIALS.
248. Composition of Cordials or Liqueurs, 497
Absinthe.
249. Composition, Adulterations, and Effects of Absinthe, . . 497, 498
FERMENTATION— FERMENTED LIQUORS.
250. General Principles of Fermentation, ..... 499, 500
251. Yeast, 500-502
252. Lactic Acid and other Ferments, 502, 503
Beer.
253. Enumeration of the various kinds of Beer — Their Composi-
tion, 503-505
254. The Water used by the Brewer, 505, 506
255. Malt Extract, 506-508
256. The Colouring-Matters of Malt, 508, 509
257. Beer Bitters, 509, 510
258. Hops, 510-514
259. Absynthin, 514
260. Aloin, 514, 515
261. Cnicin, 515
262. Daphnin, 515, 516
263. Gentianin, .......... 516
264. Gentiopicrin, 516, 517
265. Menyanthin, 517
266. Quassiin, 517, 518
267. The Ash of Beer, 518
268. Analysis of Beer, 518
Specific Gravity of Malt Extract, 522-525
Spirit Indication Tables, 526-528
Hop Resin and Glycerin, 531
The Nature of the Bitter used 532
Dragendorff's Process 532-536
CONTENTS.
xxiii
Page
Section
269. Adams' Process for Separating Hop Bitter— Processes to be
Used for the Separation of Picrotoxin and other Matters, 536-53S
270. Special Tests for Picric Acid, . ■ 538 539
271. Spectral Analysis of Beer, .... Salicylic Acid, ......
272. Ash of Beer — Determination of Salt in Beer,
273. Adulteration of Beer with Sugar, . Bibliography relative to Beer,
539, 540 540
540-543 543 544
274. 275. 276. 277.
278.
278a 279. 280. 281.
281a 282. 283.
284.
Wine.
Constituents of Wine,
Changes taking place in Wine through Age, ....
Adulterations of Wine,
Analysis of Wine— Dupre's Analyses of Wines— Schmidt's Analyses of high-priced Wines — Physical Characters, Constituents Volatile below 100° C, . . . . Volatile Acids — Estimation of free Sulphurous Acid and of
Aldehyde Sulphurous Acid,
. Estimation of Esters in Wine,
Extract or solid Residue,
Estimation of Succinic Acid and Glycerin, .... Estimation of Tartaric Acid, and Glycerin, and Bitartrate of
Potash,
Estimation of Malic Acid,
, Astringent Matters,
Estimation of Colouring-Matters in Wine, . . . . Absorption Bands of the Colouring-Matters of Wine, '.
Gatjtier's Process tor Detecting Foreign Colouring- Matters IN Wine.
Preliminary Preparation of the Sample, and Table A, . Table B — Systematic Process,
545 546 546-, 547
547-553
553-555 556, 557
557-561 561, 562
562-564 563 564
564-569 569
570 570-575
Special Reactions eor the Detection oe Certain of the Colouring-Matters mixed with Wines.
Brazil Wood,
Logwood, Cochineal, Fuchsine, Portugal Berries, HoUvhock'
575
285. 286.
Beetroot, Elder, Privet, Whortleberries, Indigo, Mineral Substances or Ash of Wine, Detection of Pluoborates and Fluosilicates, .* Bibliography relative to Wine, ....
576-578 578, 579 579 580
PART VII.— VINEGAR.
287. Constituents of Commercial Vinegar. . nRi
288. Adulterations, . . . ™ ' . .* ' * 532
289. Analysis of Vinegar, 582-588 Bibliography relative to Vinegar, . '. '. * \ \ 539
xxiv
CONTENTS.
Lemon Juice and Lime Juice.
Section Paa^o
290. Constituents of Lemon and Lime Juice, .... 599
291. Adulterations of Lime Juice, 590, 591
292. Analysis of Lime Juice, 591,592
PART VIIL— CONDIMENTS : MUSTAED, PEPPER, &c.
MUSTAED.
293. Varieties of Mustard — Microscopical Structure of the Seed, . 593-59G
294. Analysis of Mustard 596
295. The Chemistry of Mustard, 596-598
296. The Fixed and Volatile Oil of Mustard, .... 598, 599
297. Adulterations of Mustard, 599-601
Pepper.
298. Varieties and General Composition of Pepper, . . . 603 Microscopical Structure of Pepper, 604-606
299. Piperin— Piperidin— Piperic Acid, 606, 607
300. The Ash of Pepper— Nitrates and Nitrites in Pepper, . . 607, 608
301. General Composition of Pepper, 608
302. Analysis of Pepper, 609
303. Adulterations of Pepper, 609
Olive-Stones — Poivrette, 610
Legal Case relative to Pepper, 612
Bibliography, 612-614
Cayenne Pepper.
304. General Description of Cayenne, 614
305. Capsaicin and other Principles of Pepper, . . . .615,616
306. Adulterations of Cayenne Pepper, 616, 617
The Sweet and Bitter Almond.
307. General Description of Almonds, 617
308. Oil of Almonds, 617, 618
309. Amygdaline— Volatile Oil or Essence of Almonds, . . 618-620
Annatto.
310. General Characters of Annatto, 621
311. Chemical Composition of Annatto, 621,622
312. Adulterations of Annatto, 622
313. Analysis of Annatto, 623
Olive Oil.
314. General Description of Olive Oil, 623-625
315. Adulterations of Olive Oil— Refraction of Olive Oil— Tests for
Arachis, Sesam^, Cotton Seed, Rape, and Poppy Seed Oils, 625-623
CONTENTS.
XXV
PART IX.— WATER.
Section
316. Introduction,
Page 629
I. EXAMINATION BY THE SENSES.
317. Colour— Smell— Taste, 629-631
II. PHYSICAL EXAMINATION.
318. Spectrum of Water, &c., 631
III. CHEMICAL METHODS.
A. — Preliminary Qualitative Chemical Examination. Detection of Nitrites and Nitrates, 631-633^
633 634 635.
B. — Quantitative Analysis.
319. 1. Total Solid Residue,
2. Estimation of the Halogens,
3. Phosphates,
4. Estimation of Nitrates and Nitrites — (1) Colorimetric Methods— (a.) The Brucine Method; (&.) The Diphenyl- amine Method ; (c.) The Carbazol Test; {d.) Phenol and Resorcinol. (2.) Estimation as Ammonia — The Copper- Zinc Couple — The Aluminium Process — Ulsch's Method of Estimating Nitric Acid by Reduction to Ammonia. (3.) Estimation of Nitrates and Nitrites as Nitric Oxide — Crum Process. (4.) Indigo Process. (5.) Ulsch's Method of Estimating Nitric Acid by Measuring the Deficiency
of Hydrogen evolved on Reduction, 636-64ff
5. Estimation of the Dissolved Oxygen in Water, . . 646-650
6. Sulphates, 65a
7. The Forchammer, Oxygen Process, 650-654r
8. Ammonia, Free and Albuminoid, 654-656
9. Hardness, 656
10. Alkalinity, 657
11. Organic Analysis of Water, 657
Frankland's Combustion Process, 657
Blair's Method of Moist Combustion, .... 664, 665 The Author's Method of Moist Combustion, . . . 665-667 Gravimetric Estimation of Minute Quantities of Carbon, 667-670
IV. BIOLOGICAL METHODS.
319a, Estimation of Organic Nitrogen after Kjeldahl's Method, . 670, 671 Mmeral Analysis of Water, 671, 672
320, Microscopical Appearances 672
The Sedgwick-Rafter Method, 672
Mr. Dibdia's Process, 673
a. LIFELESS FORMS.
Mineral Matters — Vegetable Matters— Dead Animal Matters — Haman Debris, Manufactured Matters,
676
xxvi
CONTKNTS,
b. LIVING FORMS.
Section Pa