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GROUP VIII.

WINES, BEERS, SPIRITS AND CORDIALS.

By F. E. ENGELHARDT, Ph. D.

Prof. C. F. CHANDLER, Ph. D.,

Chairman of the Sanitary Committee of the State Board of Health: SIR: I have the honor to submit herewith the following report of my examinations of the group of foods assigned to me. It includes wines, beers, spirits and cordials; and although no samples of wine were submitted for examination, I have embodied in the report some general remarks on this division of the subject.

Very respectfully,

F. E. ENGELHARDT, Ph. D.

I. WINES.

By the term "wine" should be understood only pure grape juice, fermented and clarified.

Those preparations made from grape juice by other than the ordinary methods of procedure might be designated as "improved wines," to which could be added the name of the person originating the modification in manufacture.

Wines prepared artificially from raisins, cider, etc., with the addition of alcohol; coloring matter and other substances should be sold only as "artificial wines."

A good wine should be transparent; the color should not be too pale, and the taste and aroma should be pleasant. The sensation produced on the organ of taste, when drinking it, should not be for a moment, but lasting for some time, and the bouquet or aroma perceptible at once. When pouring it into a glass it should sparkle. A sour taste is always a sign of poor wine. If it quickly intoxicates we may suspect the addition of spirit, recognized by the more or less burning sensation in the throat, which is never produced by a good pure wine. Dizziness and headache are not produced by drinking pure wine. Cloudy, discolored, very highly colored wines are suspicious (Beyse's Kellerbüchlein). Wines are generally divided into table wines, medium wines and dessert wines, but wine experts recognize "dry wines,' greasy wines" and "cordial wines," each having three divisions according to quality:

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(Partly taken from Beyse's Kellerbuchlein and Dr. Feuchtwanger's Fermented Liquors.)

ANALYSIS OF WINE.

The analysis of wine usually comprises the determinations of the specific gravity, alcohol, extract, sugar, acidity, ash, phosphoric acid and coloring matter in red wines.

Specific Gravity. The specific gravity should always be determined by the aid of the specific gravity bottle at a temperature - if possible — of 60 deg. Fahrenheit.

Determination of Alcohol.-(a) By distillation.-Although alcohol may be determined in various ways, the distillation and indirect methods deserve the preference.

*

For distillation from 100 to 200 grams of wine are submitted to distillation in a retort or other suitable flask connected with a Liebig's condenser. When from two-thirds to three-fourths of the quantity taken have come over, the distillation may be stopped, the distillate allowed to cool to 60 deg. F., its specific gravity taken, and from the tables the amount of absolute alcohol corresponding to the specific gravity can be ascertained. From the results thus obtained we can easily calculate the per cent for the wine submitted to distillation.

*To prevent foaming of the wine during distillation, add a little tannin, and to retain the volatile acids, a little caustic alkali before distillation to the contents of the retort.

(b) By the indirect method. —If we take a certain weight of an alcoholic liquid, containing other substances in solution and remove by heat (over a water-bath at about 75 deg. C.) the alcohol and then add distilled water to bring it up to the original quantity, we can assertain the amount of alcohol according to the formala D+1,000-D' =x in which D is the specific gravity of the original mixture and D' the specific gravity of the mixture deprived of its alcohol. (Balling.) According to Thudichum and Dupré both methods with proper care give good results, but Dr. Elsner prefers the indirect method.

Determination of the Extract. — To determine the extract directly is not only most difficult, but it requires considerable time, hence it is best to adopt the indirect method of Balling just explained. Take a certain weight of the original wine (100 grams) evaporate it on the water-bath (at 75 deg. C.) to one-fourth, fill up to the same weight at 60 deg. F. and determine the specific gravity of the well mixed liquid, at about 59 deg. F. (15 deg. C.).

By reference to the accompanying table (I) the quantity of extract corresponding to any specific gravity can be ascertained. The figures of Schultze are better for wines rich in extract, but not so accurate for light wines as those of Hager. Instead of ascertaining the extract according to the table, we may ascertain the specific gravity of the evaporated, and again filled up wine, at 19 deg. F. to the fourth decimal, and multiply the two last places in the decimals by the number 2.25, the Houdart's factor (Elsner), which will give us the result at once.

TABLE 1.

Giving the Specific Gravity and corresponding amount of Extract in 100 grams of Wine, according to Hager and Schultze.

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The determination of sugar. Of the various methods that may be used for the determinations of sugar in wine, I prefer the method with Fehling's alkaline copper solution. Of light white wines I take 100 grams, and of those rich in extract 25 grams, remove the alcohol by heating over a water bath, and dilute the residue to 200 c. c. with distilled water. In the preliminary test I drop the diluted wine into the boiling copper solution (10 c. c. Fehling's to 40 c. c. distilled water) till the precipitate becomes bright red, and the blue color has entirely disappeared, filter off a few cubic centimeters, and test the latter both for copper and excess of precipitant. With a little practice very good results can be obtained by this method. I always make from two to three sugar determinations, and take the average. Colored wines must be previously decolorized with bone black, or acetate of lead solution, or both. If the presence of cane-sugar is suspected I take 100 c. c. of the diluted wine, heat it with a few c. c. conc. hydrochloric acid (C. P.) for about one hour, over a water bath at 75° C.; naturalize to alkaline re-action, fill up to 100 c. c. again, and test as before.

The optical method should be employed whenever an apparatus is

at hand.

The determimation of the total acid. In 100 grams of wine I determine the acid volumetrically either with one-tenth normal soda solution, or lime-water, using red and blue Litmus paper to determine the neutral point.

The determination of sulphuric acid. This determination is of great importance at present in wine analysis, and should never be omitted, since not only · as is asserted-sulphuric acid is added directly to wine, but it may be present as the result of plastering and sulphuring, or by the addition of impure glucose, copperas, or alum, the latter to heighten the color of red wines. Of white wines I acidulate 100 grams with hydrochloric acid, heat to boiling, and precipitate with chloride of barium. For highly colored wines I take C. Weigel's method. Supersaturate 100 grams of wine with lime-water, dilute to 200 c. c. filter through a dry filter, and precipitate the sulphuric acid in 100 c. c. by chloride of barium, after acidulation with hydrochloric acid.

The determination of ash. I use 100 grams of wine, evaporate in a platinum capsule over a water bath to dryness, incinerate at a low tempature, and repeat heating till the weight is constant. Addition of a little nitrate of ammonia will accelerate the burning.

The determination of cream-tartar. 200 grams of wine are evaporated to syrupy consistency, allowed to cool, and then mixed thoroughly with 5 volumes of absolute alcohol, and allowed to stand for 24 hours. Wash the separated cream-tartar on to a filter with absolute alcohol, dissolve in warm water, and titre with normal soda solution.

The determination of glycerine. For this determination I take 100 grams of wine, discolorized if necessary, add a few grams caustic lime, and evaporate the mixture. The residue is treated with alcohol of 90 per cent. filtered and washed thoroughly with alcohol, again evaporated, and the residue extracted with a mixure of alcohol and ether (100 parts 90 per cent. alcohol and 150 parts ether) filtered, and the filtrate evaporated at a very low temperature at last under the air pump. The treatment with lime and the extraction with the alcohol-ether mixture should be repeated twice.

If the phosphoric acid has to be determined, I take the ash dissolve

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