INDUSTRIAL d,VD E,VGINE%’RING CHEMISTRY
342
Will the X-Ray Follow the Microscope into Industry? Many years ago some hardy pioneers were introducing the microscope to industry-or, perhaps one should say, were introducing industry to the microscope. Today the microscope is a common tool in both research and control laboratories. I n many organizations micrographic examination and micrographic record of representative samples are routine practice. Now other pioneers are introducing industry to x-rays. I n one research program now being followed i t has been decided to make an x-ray pattern of every specimen of which micrographic record is taken. These may disclose nothing valuable or they may unlock the door to invaluable information. But certainly if they are not made they can show nothing. It may not be an idle dream to think of the time when an x-ray pattern will be as common and as well
1-01. 19, s o . 3
understood where technical control prevails as is the micrograph today. Where they can be used, x-rays furnish industry a powerful tool. Like many other industrial tools they are more or less expensive. X-ray equipment should not be installed until t h e adaptability of x-ray methods to the problem in hand has been demonstrated, and not then unless the benefits to be derived justify the cost. This would seem to make the tool unavailable to the organization with a small problem or a temporary difficulty. But fortunately some of the pioneers have installed equipment to take care of just such cases, so that i t is poseible to evaluate any proposed use of x-rays without too great expense. The time was when the cost of a preliminary survey would have been prohibitive in most cases. That time ha* passed and some other alibi will have to be found when the new tool might have been used profitably but was not tried.
Effect of Vacuum Distillation on Vanilla Extract’ By C. B. Gnadinger MCLAUGHLIW-GOR~~LEY-KING Co., MINNEAPOLIS, 311s~
Concentration of vanilla extract by vacuum distillat u r e w a s determined after OSCEXTRATED chopping. The menstruuni tion causes a loss of flavor and aroma. The extent of vanilla extracts have the loss depends on the degree of concentration and contained 60 per cent alcohol attained a certain dethe kind of bean. The quality of the flavor as well a s or acetone, since this percentgree of popularity with the its strength is changed. If the degree of concentration age, in the writer’s opinion. manufacturing trade because is high the aroma is almost entirely destroyed. gives the maximum extracthey are cheaper than standDistillation does not cause a marked change in chemtion of flavor and color. Tw.0 ard vanilla extract. There is ical composition, but there is a loss of volatile acids and hundred grams of chopped true economy in the use of a volatile oil. The loss of flavor and aroma is due, not beans were macerated TTith concentrated extract, which to decomposition or chemical change, b u t to volatiliza1900 cc. of menstruum, Rith is ten times standard strength, tion of flavoring materials. frequent agitation, during 3 because of the appreciable Tahiti extracts, which have been distilled, respond weeks, and the mixture was saving in alcohol, provided to tests for anisyl alcohol and piperonal. t h e n s h a k e n for 5 hours. the concentrated product reConcentrates made from acetone extracts are inThe extract was filtered, taktains the full strength and ferior to those made with alcohol. ing care to prevent evaporaquality of flavor of the beans Prime vanilla extract, which has not been subjected tion. The total volume of f r o m w h i c h it w a s made. to distillation, is superior in quality of flavor, strength extract and the exact proConcentrated extracts a l s o of flavor and aroma to vanilla extracts which have been portion of beans were calcuappeal to bottlers of vanilla concentrated. lated from the alcohol content who do not wish to install the of the menstruum and that e q u i p m e n t n e cess a r y for of the finished extract. Alcohol and acetone extracts were manufacturing vanilla extract. The work described in this paper was carried out to de- prepared from samples A and C, but only alcohol extract. termine the effect of vacuum distillation on the flavor, aroma, were made from samples B, D, and E . Different grades oi and chemical composition of vanilla extracts. Dean and beans were used, so that the effect of distillation on extracts Schlotterbeck2 concluded that vanilla beans can be dried, of moldy and sour beans could be observed. The extracts without material loss of flavor, a t room temperatures, but are described in Table I. no data could be found on the effect of distillation on vanilla Concentration of Extracts extract. The extracts were analyzed, using the A. 0. A. C. method.,‘ Preparation of Extracts and a portion of each was then subjected to vacuuni di\-
C
Concentrated vanilla extracts are made by vacuum distillation of an extract of vanilla which is prepared by percolating with dilute alcohol or acetone, and which is generally somewhat stronger than standard vanilla extract. If the distillation is prolonged the concentrated product is a viscous, semisolid mass, and is known as oleoresin of vanilla. The extracts used in the experiments t o be described were prepared with acetone and alcohol from five different sample lots of beans. The beans were chopped to pass through a No. 10 screen, and were thoroughly mixed. Mois1
2
Receibed November 4 1926 THISJ O L R N A L 8 , 607 (1916)
tillation. The seven extracts were evaporated to concentrations ranging from 2.24 to 26.11 times standard strength. The extract was carefully measured into the glass still, and the conditions were kept as near as possible to those existing in commercial vacuum distillations. After distilling, the apparatus was cooled and the extract mas diluted to its original volume, with approximately the alcohol content that it had before distilling; the concentrates dissolved completely and filtration was not necessary. Extracts 2 and 5 were made with acetone, and after distilling they were diluted to the original volume n:th the 3
A.;soc O f i c i ~ l1 r C’lrm
h f e t h o d s p 349 (1923)
I S D USTRIAL A N D ENGINEERISG CHEMISTRY
March, 1927
343
Table I-Description of Beans a n d Extracts Used (200 grams beans to 1900 cc. menstruum) ~
BEAN EXTRACT SAXPLE No.
MOISTURE
DESCRIPTION OF B E A K S
(VOL. A T
1000
C.)
Per cenl .I
.-I
E
C
C
D
E
1 2 3
2 !
Prime Mexican; odor sweet; condition and color good; length 21 cm. Part of same sample of beans used in extract 1 Second grade Bourbon; odor good: slightly dry; crystallized; length 18 cm. Prime Bourbon; excellent quality: slightly crystallized; length 20 cm. Part of same sample of beans used in extract 4 Bourbon “Vrac.” Slightly moldy and sour;very poor quality; length 10 cm. Tahiti beans: slightly offodor and slightly moldy; length 13 cm.
same alcohol content as extracts 1 and 4, respectively. The distillation data are given in Table 11. After concentrating the extracts and diluting them to their original volumes, they were again analyzed. I n Table I11 the analyses, before and after Concentrating, are given. Extracts 2 and 5 were made from the same beans as extracts 1 and 4, using acetone instead of alcohol. Extracts 2 and 5 after distillation are, therefore, compared with extracts 1 and 4, respectively, before distillation. Discussion of Analyses
determined by spontaneous evapoTotal extractive ration before a fan and drying on sand to constant weight over sulfuric acid. It was impossible to determine accurately the non-volatile (and volatile) extractive because of the a p parent decomposition, with loss of water, during drying by the A. 0. A. C. methods. The differences in total extractive, between the original and distilled extracts, are within the limits of error of the method. There was little or no loss of vanillin, except in the distillation of KO. 6, which was evaporated quite rapidly; the distillate from No. 7 , which was heated to 60’ C., also contained some vanillin. The lead numbers were unchanged after distillation. It is interesting to note that the acetone extracts, 2 and 5, had lower lead numbers than the alcohol extracts, 1 and 4, made from the same beans. The ash and P205 were, as expected, not affected by distillation; those of the acetone extract were slightly lower than the corresponding alcoholic
34.76 34.76 25.45 30.02 30.02 28.64
...
~
ALCOHOLI N BEANSPER MENSTRUUM FINISHED 100 cc. EXTRACTE X T R A C T
Per cent Alcohol Acetone Alcohol Alcohol Acetone Alcohol Alcohol
60.24 60.0 60.24 60.24 60.0 60.24 50.04
Per cent
Grams
57.80
10.11 10.11 10.14 10.18 10.18 10.22 10.00
58106 58.30
5 8 : 50
...
100 cc. of extract, or grams per 10 grams of beans. convenience these figures are tabulated below. Grams extractive Sample A B C
per 10 grams beans
For
Pounds beans equiv. extractive
t o 1 pound
3.2 2.2 3.1
D
3.5
The highest concentration can be obtained with sample D , which is the poorest bean of the four samples. Commercial , ~ that the oleoresin contains 25 to 50 per cent m o i ~ t u r e so concentrations of commerciai products would be lower than those in the third column, which are calculated from the dry
extractive‘ Comparisons of Flavor and Aroma
The distilled extracts were compared with the originals for flavor and aroma. These comparisons were made with 3 per cent and 5 per cent dilutions in distilled water, and in every case the original extracts were stronger in flavor and aroma than the corresponding distilled extracts. The loss in flavor and aroma increased with the degree of concentration. iln attempt was made to express this loss quantitatively by comparing different dilutions of the distilled extracts with the 5 per cent solutions of the original extracts; the alcohol content was adjusted in making the comparisons. It was impossible to express the loss in flavor accurately in percentages, but comparisons by a number
Table 11-Concentration of Extracts i n Vacuo (500 cc. distilled)
BEAN
SAMPLE
EXTRACT No.
TEMPERATURE
ORIGINAI, WEIGHT
PRESSCRE
WEIGHT OF
CONCENTRATE
DECREE OF CONCENTR4TIOX (BY
BEAN^ PER
500 cc
EXTRACT
WT.) O
.-I .4
B
C C
D
E
1 2 3 4 5
6 7
28 28 28 28 28 28 28
c. to to to to to to to
38 40 44 42 45 42 60
Mm.
Hozrrs
Grams
Grams
45 t o 50 50 to 5 5 45 to 50 45 t o 50 45 to 50 45 t o 50 45 to 50
1.0 1. 0 1.6 2.0 2.0 1.5 1.5
462 460 464 460 460 463 470
172 205 92 48 19 28 18
extracts. The total acidity was lower in the distilled extracts than in the originals. The acidity other than vanillin was also lower after distillation. Reducing sugars, sucrose, nonsugar solids, and vanilla resins were not changed by distillation. The resins in the acetone extracts were 50 per cent higher than in the alcohol extracts. Anisyl alcohol and piperonal were not present in the Mexican and Bourbon extracts, but mere found in the Tahiti extract before and, after distilling, and also in the distillate. The analysis of extract 3 is interesting because of the exceptionally high vanillin content, 0.415 gram per 100 cc. That this is not due to added vanillin is proved by the high total extractive, sugar content, and nonsugar solids. The maximum degree of concentration obtainable can be calculated from the amount of total extractive in the different samples. The amounts in Table 111 are grams per
2.65 2.24 5.04 9.60 24.21 16.54 26.11
DE~KS
EQVIV
t o 1 GRAM CONCENTRAP&
Grams
Grams
50.55 50.55 no. 70 50.90 50.90 51.10 50.00
0.29 0.25 0.55 1.06 2.68 1.83 2.78
STAXDARD
EXTRACT Eornv. 1 GRAM CONCEN-
TO
TRATE
cc. 2.9
20 .. 5J
10.6 2R.8 18.3 27.8
of observers placed the loss at not less than 10 per cent when the degree of concentration was 5 or greater. The loss of aroma was more pronounced than the loss in flavor, and the aroma of the more concentrated extracts had almost entirely disappeared. Extract 1 was slightly weaker after distillation, but the difference in flavor and aroma was not marked, as the degree of concentration was only 2.68. Extract 2 was inferior to extract 1 before, and extract 1, after distillation. Extract 3 lost a t least 10 per cent in flavor. Extract 4 showed a slightly greater loss in both flavor and aroma than No. 3. The flavor of No. 5 was quite different from S o . 4 and was inferior. Extract 6 had a very poor flavor both before and after distillation; the quality of flavor of extract 6 was not improved by distillation. The Tahiti extract, S o : 7 , lost more than 40 per cent of its flavor; Wilson and Sale, THISJOURNAL, 18, 283 (1926).
INDUSTRIAL A N D ENGINEERING CHEMISTRY
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Vol. 19, No. 3
Table 111-Analyses of Extracts before a n d after Vacuum Distillation
I ANALYSIS
Degree of concentrationa Alcohol, per cent by volume Total extractive Vanillin Lead number (Winton) Ash PzOr in ash, mg. per 100 cc. Total acidityb Acidity equivalent to vanillinb Aciditv other than vanillinb Reducing sugar as invert: Before inversior After inversion Sucrose (by copper) Nonsugar solids Vanilla resins Anisyl alcohol Piperonal b
1 I
SAMPL& A &XT. 1
Before 1.0 57.80 3.14 0.239 0.52 0.272 18.2 42.1 15.7 26.4 0.96 1.47 0.48 1.70 0.10 0 0
SAMPLE B EXT.
2
EXT.
After
After
Before
After
2.68 61.06 3.10 0.242 0.50 0.274 17.5 40.1 15.9 24.2 1.00 1.48 0.46 1.64 0.10
2.24 57.92 3.12 0.243 0.44 0.260 10.6 40.0 15.9 24.1 1.00 1.47 0.45 1.67 0.15 0 0
1.0 58.06 4.61 0.416 0.49 0.251 9.4 52.7 27.3 25.4 1.50 2.39 0.85 2.26 0.13
5.04 59.20 4.59 0.415 0.49 0.264 9.5 Tj0.1 27.3 22.8 1.51 2.41 0.86 2.12 0.13 0 0
0 0
0
0
I
SAMPLE C
S.4MPLE D
I
SAMPLE E
1
Before After
3 Before
After
0
0
0
0
I
After
0 0
I Before 1.0 58.50 2.89 0.137 0.52 0.278 11.8 35.8 9.0 26.8 0.69 1.03 0.32 1.88 0.08
0
After 16.54 58.94 2.91 0.130 0.54 0.275 11.8 33.7 8.5 25.2 0.72 1.02 0.29 1.90 0.08 0
1.0
26.11
+ ++ i
See Table 11. Cc. 0.1 N alkali per 100 cc. extract; other results in grams per 100 cc. unless otherwise noted
this was because the flavor of Tahiti vanilla is largely due to the volatile oil. The acetone extracts were distinctly inferior to the alcohol extracts in flavor. This was due, not to acetone, but apparently to acrid material extracted by the acetone but not by alcohol. The distillates were extracted with ether, which was evaporated spontaneously. The residues had the characteristic odor of the volatile oil of vanilla. The distillate from the Tahiti extract was rich in anisyl alcohol and piperonal. Owing to the minute proportion of volatile oil in the distillate, it is not feasible to extract it and return it to the concentrate. Portions of the different original extracts were heated a t 98” C. in sealed flasks for 1 to 4 hours. On cooling to room temperature and comparing with the original extracts, little or no difference in flavor and aroma was found. The 5 per cent dilutions were similarly heated, with little effect on the flavor and aroma. These experiments indicate that there is no appreciable decomposition of flavoring material, a t the temperature employed, but that loss of flavor is due to volatilization of flavoring material. Comparative Value of Vanilla Extract and Concentrates
It has been shown that when vanilla extract is concentrated there is a loss of volatile acids and volatile oil, and a corresponding loss of flavor and aroma, varying from 10 to 40 per cent, depending on the degree of concentration and kind of bean. This loss is not merely a weakening of the flavor, but is a change in the quality as well.
The liquid concentrates used by ice cream manufacturers and bakers are usually claimed to be a t least eight times standard strength; that is, 80 gallons of standard vanilla extract have been evaporated to 10 gallons. I n such a concentration approximately seven-eighths of the alcohol is recovered, or about 30 gallons of 95 per cent alcohol. This represents an apparent saving of about $1.60 on each gallon of standard strength vanilla. After January 1, 1927, the alcohol tax will be reduced $1.04 per wine gallon, and the apparent saving will be about $1.20 instead of 31.60. A second reduction in tax, scheduled for January 1, 1928, will reduce the apparent saving to about 80 cents. It is obvious that the sale of concentrated vanilla depends almost entirely on the high tax on alcohol. If the tax were abolished the saving on alcohol would be very little greater than the cost of distillation. On the other hand, the loss in strength must be considered. The net saving will, of course, depend on the market price of vanilla extract and the loss of strength in concentrating. At the present price of vanilla extract a loss of strength of 25 per cent would exactly counterbalance the saving on alcohol. Examination of a number of commercial concentrates disclosed that, when diluted to standard strength, they are, if free from adulteration, weaker in flavor and aroma than standard vanilla extracts. This deficiency in flavor and aroma was made up, in several of the samples examined, by the addition of flavoring materials foreign t o vanilla; the resulting mixtures were strong, but the flavor was not vanilla.
Recovery and Utilization of Waste Liquors in the Pulp Industry‘ By Umberto Pomilio BLETTROCHIMICA POJIILIO, NAPLES,ITALY
PPROXIMATELY 50 per cent of the weight of wood and annual plants used in pulp manufacture is obtained as pulp. This leaves a large tonnage of lignin and other carbohydrates, rosins, albuminates, etc., to run to waste. I n 1922 in the United States alone 5,550,000 cords of wood were converted into pulp, with the concurrent waste
A
1 Presented under the title “A-ew Lines for the Recovery and Utilization of Waste Liquors in the Pulp Industry” before the Dlvision of Industrial and Engineering Chemistry at the 72nd Meeting of the American Chemical Society, Philadelphia, Pa., September 5 to 11, 1926.
of many millions of pounds of organic substances. The pulp industry has long realized that the question of its wastes and by-products is a serious one, and although large sums have been spent a complete solution has not been attained, particularly with respect to the sulfite wastes. It is true that a small amount of alcohol and certain colors, medicinals, and explosive materials have been derived from the waste liquors from pulp mills, but the processes are complex, the yields low, and the costs high. Much of the difficulty is due to the low concentration of solids in the liquors
