Treatise on applied analytical chemistry

556 Pages·2009·11.193 MB·English

by  Gerolamo Vittorio Villaveechia

T R E A T I SE ON
A P P L I ED A N A L Y T I C AL C H E M I S T RY
T R E A T I SE ON
A P P L I ED A N A L Y T I C AL
C H E M I S T RY
M E T H O DS A ND S T A N D A R DS
for the Chemical Analysis of the Principal
Industrial and Food Products
By
P R O F E S S OR V I T T O R IO V I L L A V E C C H IA
Director of the Chemical Laboratories of the Italian Customs
WITH THE COLLABORATION OF
G. FABRIS A. BIANCHI G. ARMANI
G. ROSSI G. SILVESTRI G. BOSCO
R. BELASIO F. BARBONI A. CAPPELLI
TRANSLATED BY
T H O M AS H. POPE, B.Sc, A.C.G.I., F.I.C.
University of Birmingham
VOL. II.
WITH IO5 ILLUSTRATIONS IN THE TEXT
LONDON
J. & A. C H U R C H I LL
7 GREAT MARLBOROUGH STREET
1918
TRANSLATOR'S NOTE
* ** the preparation of the present translation, the points on which it
**H t ^ en considered desirable to depart from the sense of the Italian text
»*• £V*-vv and mostly unimportant. Notification is made where any appre-
addition to or modification of theoriginal has been made to bring
conformity with the conditions in this country.
Temperatures are always expressed in degrees Centigrade, and concen-
r» t i o ns of aqueous alcohol solutions, according to the French custom, in
•^rc^ntages by volume.
THOMAS H. POPE.
& imtingham.
CONTENTS
PAGE
CHAP. I —Meat and its Preparations . . . . . .. i
Meat . . . . . . . . . . .. i
Sausages 3
Meat extracts . . . . . . . . .. 10
Tinned meats . . . . . . . . . .. 17
CHAP. II.—Milk and its Products 22
Milk . . . . . . . . . . .. 22
Table I. Standards for milk in Italian cities . .. 30
Preserved milk . . . .. . .. . . 32
Butter . . . . . . . . . .. 35
Table II. Distinctive reactions for butter colouring matters . 40
Table III. Mean composition of butters . . .. 43
Skim milk butter . . . . . . . .. 43
Artificial butter . . . . . . . . .. 44
Cheese . . . . . . . . . .. 44
CHAP. III.—Flour, Starch, and Derived Products . . .. 49
Flour 49
Table IV. Compositions of wheat offals . . .. 68
Bread . .. 68
Macaroni, vermicelli, etc. . . . . . . .. 73
Table V. Examination of yellow dye m macaroni, etc. - 76
Starches 77
Dextrin . . . . . . . . . .. 79
CHAP. IV.—Sugars and Products containing them . . .. 82
General methods . . . . . . . . .. 82
Hydrometric method . . . . . . .. 82
Table VI. Relation, between degrees Brix and the specific
gravity at 17-5° C. . 85
Table VII. Relation between degrees Brix and the specific
gravity at 20° C. . . . » . . • . . 88
Table VIII. Correction, of degrees Brix to 17*5° C. . - £X
Table IX. Correction of degrees Brix to ao° C. . . 92
Refractometric method . . . . . .. - 93
Table X. Relation between refractive index and concentration
of sugar solutions . 94
Table XI. Temperature correction, of the refractive index . 95
Polarirnetric method . . . . . . .. 96
Chemical method . . . . . . . .. io£
ix
x CONTENTS
PAGE
Table XII. Glucose corresponding with copper reduced (Allihn) no
Table XIII. Invert sugar corresponding with copper reduced
(Meissl) . . . . . . . . . . in
Table XIV. Maltose corresponding with copper reduced (Wein) in
Table XV. Lactose corresponding with copper reduced (Soxhlet) 112
Table XVI. Constants of the principal sugars . . .113
Determination of the sugars in their mixtures . . . .114
Special Part . . . . . . . . . .. 122
Prime materials and products of the sugar industry . . .122
Beet 123
Diffusion juices . . . . . . . .. 126
Defecated juices . . . . • . . . . .129
Dense juice and syrup . . . . . . . .129
Massecuite . . . . . . . . . .131
Molasses . . . . . . . . . .. 132
Raw sugars . . . . . . . . .. 133
Table XVII. Invert sugar corresponding with copper (Herzfeld) 136
Table XVIII. Factors for the calculation of invert sugar . 136
Refined sugars. . . . . . . . .. 139
Exhausted slices . . . . . . . . .140
Waste and wash waters . . . . . . . .140
Filter-press sludge . . . . . . . . .140
Other sugars . . . . . . . . .. 141
Glucose . . . . . . . . .. 141
Maltose . . . . . . . . . .. 143
Invert sugar . . . . . . . . .. 145
Products containing sugars . . . . . . . • *45
Crystallised and candied fruits . . . . . . .145
Preserved fruit 149
Jams 149
Chocolates . . . . . . . . .. 152
Sweetmeats . . . . . . . . .. 156
Jujubes . . . . . . . . . .. 156
Biscuits and milk flour . . . . . . . . 157
Marzipan. . . . . . . . . .. 158
Citrate of magnesia . . . . . . . . .158
Honey . . . . . . . . . . 159
CHAP. V.—Beer 164
Specific gravity . . . . . . . 164
Original gravity and alcoholic strength . . . . .165
Table XIX. Original gravity table . . . .165
Table XX. Correction of spirit indication for acidity . 166
Determination of ash . . . . . . .. 166
„ chlorides . . . . . .. 167
acidity 167
„ carbon dioxide . . . . .. 168
„ glycerine . . . . . .. 168
„ maltose . . . . . .. 168
„ dextrin . . . . . .. 169
„ nitrogenous substances . . .. 169
Detection of antiseptics . . . . . .. 169
., artificial sweetening agents . . . .171
„ extraneous bitter substances . . . .171
„ injurious metals . . .. . . . 172
„ pasteurisation . . . . . . .172
C O N T E N TS xi
PAGE
Forcing test . . . . . . . .. 172
Determination of arsenic . . . . . . . 1 73
CHAP/ VI.—Wine 175
External examination . . . . . . . . 1 76
Specific gravity . . . . . . . . - 1 77
Alcohol content . . . . . . . . . 1 77
Table XXI. Alcohol table I?9
Extract . . . . . . . . .. 182
Table XXII. Extract table 184
Determination of ash . . . . . . . . 1 89
alkalinity of the ash . . . . . 1 90
,, acidity . . . . . .. 191
tartaric acid . . . . .. 193
sugars . . . . . .. 194
Detection of dextrin and impure glucose . . . . 1 96
Determination of the glycerine . . . . . . 1 97
Measurement of the colour . . . . .. 199
Detection of extraneous colouring matters . . .. 200
Determination of the sulphates . . . . . . 2 03
,, ,, chlorides . . . . .. 204
Investigation of the nitrates . . . . . .. 205
Determination of the phosphoric acid . . . .. 206
Detection of citric acid . . . . . . .. 208
free mineral acids . . . . .. 208
Table XXIII. Values of a : b 211
Detection and determination of antiseptics . . . . 2 11
Detection of artificial sweetening agents . . . . 2 15
,, and determination of extraneous metals . . 2 17
Microscopic examination . . . . . . . 2 19
Vinegar . . . . . . . . . .. 222
CHAP. VII.—Spirits and Liqueurs . . . . . .. 229
General methods . . . . . . . . .. 230 0
Objective characters . . . . . . .. 230
Determination of alcohol . . .. . .. 230
Table XXIV. Alcoholic strength from specific gravity . 234
Determination of the extract and ash . . . . .238
Detection and determination of impurities . . .. 238
Table XXV. Dilution of alcohol to 90% strength . . 238
Table XXVI. Strengthening of dilute spirit to 50% con-
centration by means of 90% alcohol . . . .. 240
Table XXVII. Dilution of strong alcohol to 50% concentra-
tion 241
Determination of the acidity. . . . . .. 243
,, ,, esters . . . . . .. 243
Detection and determination of the aldehydes . . . 244
furfural . . .. 246
Determination of the higher alcohols . . . .. 246
Detection and determination of metals . . . .. 250
„ ,, denaturants . . .. 251
„ methyl alcohol . * . 258
Special part * 260
Industrial spirit . . . . . . . . .. 260
Table XXVIII. Composition of industrial spirits * • 261
Xll CONTENTS
PAGE
Fusel oils . . . . . .. 26l
Eau-de-vie . . . . . . .. 262
Table XXIX. Compositions of eaux-de-vie 263
Cognac . . . . . . . .. 263
Table XXX. Compositions of cognacs 265
Rum « . . . . *. 265
Table XXXI. Compositions of genuine rums 266
Fruit spirits . . . . . . .. £66
Table XXXII. Compositions of fruit spirits 269
Cereal spirits . . . . . . .. 269
Table XXXIII. Compositions of whisky and gin 270
Liqueurs . . . . . . . .. 270
CHAP. VIII.—Essential Oils 274
General methods . . . . . . .. 274
External characters . . . . .. 275
Determination of the specific gravity 275
„ „ rotatory power 275
,, „ refractive index . 276
,, „ solidifying point . 277
,, „ boiling point 278
,, „ solubility . . .. 278
„ „ esters . . . .. 279
„ „ free alcohols 280
,, „ aldehydes . . .. 281
„ „ phenols . . .. 282
Special investigations . . . . .. 282
Special part . . . . . . . .. 285
Bitter orange oil . . . . - . 285
Sweet orange oil . . . . . .. 285
Bergamot oil . . . . . .. 286
Oil of lemon . . . . . . .. 289
Other essential oils . . . . . .. 298
Table XXXIV. Characters and compositions of the com-
moner essential oils 292
CHAP. IX.—Turpentine and its Products 299
Turpentine . . .. 299
Oil of turpentine 301
Colophony . . .. 306
Resin oils • 309
CHAP. X.—;Varnishes 313
Practical tests
313
Chemical analysis
3*4
Table XXXV. Densities and boiling points of solvents for
varnishes
317
Table XXXVI. Characters of solvents for varnishes 3*7
CHAP. XI.—Rubber and Guttapercha 321
Raw and purified rubber 321
Factis . . . . .. 324
Vulcanised and manufactured rubber 325
Ebonite 329
Guttapercha . . . .. 329
CONTENTS xiii
PAGE
CHAP, XII.—Tanning Products 331
Prime materials and tanning extracts . . . . . 331
Qualitative examination . . . . . . 331
Table XXXVII. Reactions of tanning substances . . 334
Quantitative analysis . . . . . . . -337
Table XXXVIII. Compositions of tanning materials . . 346
Tannin . . . . . . . . . .. 346
CHAP. XIII.—Inks 348
Qualitative tests . . . . . . . . • 348
Quantitative analysis . . . . . . . -352
Practical tests . . . . . . . . -353
CHAP. XIV.—Leather 355
Tanned leather . . . . . . . . • 355
Physical and mechanical tests . . . , . -355
Chemical analysis . . . . . . . -357
Table XXXIX. Compositions of various sole leathers . 362
Chromed leather . . . . . . . . -364
Physical and mechanical tests . . . . . -364
Chemical analysis . . . . . . . .364
CHAP. XV.—Colouring Matters 366
Mineral colours (pigments) . . . . . . .. 366
General methods . . . . . . . . .. 366
Technical tests . . . . . . . .. 366
Chemical analysis . . . - . . .370
Special part . . . . . . . . . .. 372
White pigments . . . . . . . .. 372
Table XL. Scheme for the recognition of white pigments . 373
White lead . . . . . . . . .. 372
Zinc white . . . . . . . . .. 375
Lithopone . . . . . . . . .. 377
Permanent white . . . . . . . .. 378
Red and yellow pigments . . . . . . • -379
Table XLI. Scheme for the recognition of red and yellow
pigments . . . . . . . .. 380
Chrome yellow, Chrome red . . . . . . -379
English red . . . . . . . . .. 381
Ochres 383
Minium . . . . . . . . . .. 384
Cinnabar, Vermilion . . . . . . .. 386
Cadmium yellow . . . . . . . .. 387
Green and blue pigments . . . . . . . .388
Table XLII. Scheme for the recognition of blue and green
pigments . . . . . . . .. 389
Ultramarine . . . . . . . . .. 390
Prussian blue, Turnbull's blue . . . . . .. 392
Greens and blues with a copper basis . . . .. 393
Chrome green 395
Mixed chrome greens . . . . . . .. 395
Terre verte * 396
xiv CONTENTS
PAGE
Brown, grey and black pigments . . . . .. 396
Table XLIII. Scheme for the recognition of brown, grey and
black pigments . . . . . .. • 397
Umber -398
Cologne earth 399
Graphite 399
Black pigments with a basis of carbon . . . .. 400
Metallic pigments . . . . . . . . .401
Lakes 4O2
Organic colouring matters . . . . . . .. 4°4
Dye woods and barks and their extracts . . . • 4°5
Logwood extract . . . . . . .. . 4°7
Red wood extract 4°9
Yellow wood extract . . . . . . . .410
Quercitron extract . . . . . . . .410
Indigo . . . . . . . . . . .411
Indigo carmine . . . . . . . .. 416
Alizarin . . . . . . . . . .. 416
Catechu, Gambier . . . . . . . . .419
Cochineal 420
Carmine . . . . . . . . .. 421
Artificial organic colouring matters . . . . .. 422
Identification of colouring matters. . . . • • 424
Table XLIV. Basic and basic mordant dyestuffs . • 427
Table XLV. Salt and sulphur dyestuffs . . . .428
Table XLVI. Acid and acid mordant dyestuffs . . . 43°
Table XLVII. Dyestufis insoluble in water . . . 432
Table XLVIII. Reducible and non-reoxidisable dyestuffs . 434
Table XLIX. Reducible and reoxidisable dyestuffs . -435
Table L. Non-reducible aminic dyestuffs . . . • 43$
Table LI. Non-reducible phenolic dyestuffs . . -437
Detection of extraneous substances in colouring matters. . 438
Tintorial value of colouring matters . . . .. 440
CHAP. XVI.—Textile Fibres, Yarns, Fabrics 44*
Microscopic examination . . . . . . .441
Table LII. Microscopic characters of vegetable fibres. . 445
Table LIIL Microscopic characters of animal fibres . . 451
Chemical examination . . . . . . . -455
Tables LIV, LV, LVI, LVII, LVIII, LIX, LX. Identification
of colouring matters on wool . . . . -477
Tables LXI, LXII, LXIII, LXIV, LXV, LXVI, LXVII.
Identification of colouring matters on cotton . -497
Physico-mechanical examination . . . . . .528
TO THEVTWX) VQLTTME§ . . . . . .. 329
LIST OF PLATES
PAGE
Plate I.—Wheat and rye hairs, and various starches . .. 82
Plates II, III and IV.—Various starches 82
Plate V.—Various starches, dextrin and ivory-nut meal . . 82
Plates VI-XT.—Textile fibres End