THE ANALYST. 33 ABSTRACTS OF PAPERS PUBLISHED IN OTHER JOURNALS. ___---_ ___ FOODS AND DRUGS ANALYStS. (Zeit. fiir Untersuch. der Nahr. ztnd GenussmitteE, 1898, 678-683.)-The following method is proposed : 300 grammes of milk are weighed and transferred to eight test-glasses 15 cm. long by 1.5 cm. wide. These are then plrtced in a centrifugal apparatus, which is rotated at a speed of about Determination of Dirt in Milk. R. Eichloff.34 THE ANALYST. thirty revolutions a minute for five minutes. The dirt settles completely to the bottom. The cream and the greater part of the milk are now carefully removed, leaving the sediment undisturbed, and the remainder of the milk with the sediment is then washed out into a fresh tube ahd again centrifuged. The sediment is finally filtered off, with the help of a filter-pump, through a dried and weighed asbestos filter-tube, which is then thoroughly washed, dried, and re-weighed. H.H. B. S. On the Changes which take place in Milk Fat during the Ripening of Cheese. A. Eirsten. (Zeit. fur Untersuch. der Nahr. und Genusmittel, 1898, 742.)- The results obtained are shown in the following table. They are in every case the mean of duplicate experiments : Reichert- 1 I I 1 Meissl- I Number 1 Refracto- 1 Wollny meter Number Days Number at (c.c. EaO I Date. I 1 Ripening* I 250 c. I for 5 Grammes of fat). 1 2. 3. 4. 5. 17, 5, '96 27, 5, '96 3, 6, '96 10, 6, '96 17, 6, '96 2* 3. I 15,10,'96 2110,'I 1.. 25, 2, '97 2. I 24, 8, '97 1 1. 7, 1, '97 2. I 3, 11, '97 I 0 10 17 24 31 Kottstor- fer Num- ber (Milli- grammes, KHO re- quired for saponify- ing 1 Gramme).Hehner Number (Insoluble Fatty Acids from 100 Parts of Fat), I.-FAT FROM CAMEMBERT CHEESE. 27.1 ::'? 1 27.1 52.7 26-6 52 *7 26.6 52.4 1 26.9 227 227 226 225 225 87.6 87.2 87.7 87.4 87 -4 II.-FAT FROM NEUFCH~TEL CHEESE. 0 53.7 29.1 226 87.3 18 31 III.-FAT FROM TILSIT FAT CHEESE. 0 181 0 300 Remarks. Cheese ripe. Cheese over- ripe. Cheese ripe. 52.2 27.9 226 87.7 52.1 1 27.3 1 224 I 87-4 [ Cheese ripe. 53.1 27.5 229 88.4 52-4 1 27-5 I 227 1 88.1 I Cheese ripe. IV.-FAT FROM DUTCH CHEESE. H. H. B. S. Detection of Cane-Sugar in Wine, Saccharine Liquids, etc. G. Papasogli. (Giorn. di Farm. di Trieste, 1898, iii., 301 ; through Chem. Zeit. Rep., 1898, 320.)- An aqueous solution of cane-sugar gives a fine permanent amethyst colour when it is mixed with a cobalt salt and a small excess of caustic soda, and the tint is visible even in 0.05 per cent.solutions. Grape-sugar yields a blue which rapidly bleachesTHE ANALYST. 35 and finally becomes dirty green. Dilute glycerin only produces a faint green. SoIutions containing 20 per cent. of alcohol, 10 per cent. of cane and 10 per cent. of grape sugar respectively, coloured with caramel, were prepared. 15 C.C. were decolorized with 0-5 gramme of animal charcoal, filtered, treated with 0.5 C.C. of a 5 per cent. solution of cobalt nitrate, shaken, and then 2 C.C. of 50 per cent. caustic soda were added: the reactions appeared in every case, The amethyst colour characteristic of cane-sugar can be recognised even when the sugars are composed of 9 parts of grape to 1 of cane sugar.Wines must be bleached with lead acetate to remove colouring matter and tartaric acid. Condensed milk may be diluted with twice its volume of water, and treated with lead acetate. Gum and dextrin must be removed either with the normal or ammoniacal acetate of lead. F. H. L. The Detection of Starch in Black and White Mustard Seed. J. W. Lloyd. (Amer. Jozw. Pharm., 1898, Ixx., 433-439.)-The ordinary method of testing for starch by adding iodine solution to the aqueous decoction may fail with black mustard, owing to the liberation of mustard oil when the mustard comes in contact with water. This oil combines with the iodine, and when only a small quantity of starch is present no blue colour is obtained. The author has found that copper sulphate has the property of preventing the formation of the oil of mustard even when used in a solution of 0.2 per cent.strength, and also that on boiling the mustard seed with a solution of potassium iodide the same result is attained. C. A. M. ____ - ~_ The Estimation of Gelatin in Gums and Food Substances. A. Trillat. (Ann, de Cliim. Anal. AppZ., 1898, iii., 401,402.)-The property which formaldehyde possesses of forming insoluble compounds with proteid substances was applied by Beckmann (ANALYST, xx., 44) to the estimation of gelatin and albumin in peptones. A similar process is here advocated for the detection and estimation of gelatin in general, and especially when mixed with gums. The substance under examination is dissolved in water, the insoluble matter removed by filtration or decantation, and the solution evaporated to the consistence of a syrup.About 1 C.C. of commercial formalin is then added, and the evaporation continued till the mass becomes pasty. The residue is taken up with boiling water, which dissolves the gum and leaves the insoluble gelatin compound. After standing for twenty-four hours, the clear or slightly opalescent supernatant liquid is decanted, and the precipitate washed with boiling water, dried on the water-bath, and weighed. In a test analysis of a mixture consisting of 85 grammes of gelatin, 20 grammes of gum arabic, and 10 grammes of sugar, the gelatin was determined within 1 per cent. of the actual quantity. I n all cases the sabstance should be brought .to a pasty consistence before adding the formaldehyde, since in a dilute solution no precipitate is obtained.The gelatin of the jellies of commerce is determined in a similar manner. C. A. &I.36 THE ANALYST. Glazed Coffee. E. Hanausek. (Oesterr. Chezn. Zeit., 1898, i., 482.)-A new substance for glazing coffee-berries, in order (so the makers assert) to prevent loss of aroma and of caffeine, and improve the material commercially, chemically, and physiologically, consists of shellac. This is being put on the German a d Austrian markets in small angular orange fragments by G.iSchneider Nachfolger, of Ludwigs- hafen a/R., and is to be employed in amounts of 0.5 to 1-0 per cent. according to the time of preservation desired. F. H. L. The Occurrence of a Ptomaine in Coffee.S. Bein. (Zeits. nngew. Chew&., 1898, 658-661.)-A sample of coffee which had caused symptoms of poisoning in the members of a family which had drunk the infusion was examined by the author. I t was found to contain none of the usual metallic or alkaloidal poisons, and was free from artificial beans. It consisted of a mixture of black, over-burnt beans, including fragments of husks, etc., with about 18 per cent. of beans of a lighter colour, containing about 18 milligrammes of caffeine in 100 grammes. The black part of the mixture contained no caffeine, and had a coating on the surface in which was 0.42 per cent. of sodium chloride. On testing, the coffee gave indications of the presence of a ptomaine. As to the origin of the ptomaine, the following explanation is suggested : There are in cominerce a number of worthless products, consisting of mixtures of various kinds of spoilt coffee, such as that damaged by sea-water, etc., and known as L‘ Triage.” These are commonly mixed with a sinall proportion of a better substance, in order to render the article saleable as coffee.Since normal coffee only contains about 0.01 per cent. of sodium chloride, the author regarded the presence of the large percentage of that salt in the black part of the mixture as proof of its having been damaged by salt-water in transit. If such coffee were then stored in a damp con- dition in a badly-ventilated room, a decomposition of the proteid substance of the bean would soon be brought about. That under these circumstances ptomaines may be produced was proved experi- mentally.The authors suggest as a further cause, the roasting of the damaged coffee until black, with the object of concealing its decomposed appearance. On over-roasting, deep-seated changes occur; there is decomposition of the fat, of the proteids, of the coffee-tannin, and of the woody fibre, and bodies with objectionable smell are produced in considerable quantity. From the proteids especially pyrrol substances are derived, and these do not escape completely, but are partially condensed on the beans. The caffeine also is &destroyed, and methylamine and its derivatives are formed in sufficient quantity to impart their characteristic objectionable odour. From an experimentally over-roasted coffee the author prepared an aqueous extract, from which he succeeded in isolating pyrrol bodies and amine bases.The fact that no caffeine was found in the black portion of the coffee mixture can thus be accounted for by too high a roasting. The author points out that these products of over-roasting (amine bases pyrrol derivatives, stc.) are capable of producing very similar symptoms in animals to those produced by the products of putrefaction, even when in very dilute condition. c. A. M.THE ANALYST. 37 An Adulterated Gamboge. J. F. Woolsey. (Aiiber. Jozcr. Plzarm.) 1898, lxx., 446)447.)-Powdered gamboge as usually obtained is of a bright orange yellow colour, and contains 70 to 80 per cent. of resin, 3 to 4 per cent. of ash, 4 to 6 per cent. of moisture and gum, The trace of starch usually met with is not regarded as an adulteration, and is due to the method of collecting and packing. The author has recently met with a sample of a dull ochre colour, which was heavily adulterated. On treatment with 95 per cent. alcohol less than 40 per cent. dissolved. The added substance was found to consist of starch or flour (cf. ANALYST, xxi., 266). C. A. M. A good gamboge contains 75 per cent. of resin. - ~- -- -~ . _ .