8 THE ANALYST. ABSTRACTS OF PAPERS PUBLISHED IN OTHER JOURNALS. FOODS AND DRUGS ANALYSIS. A Modification of the Sulphuric Acid Test for Formaldehyde in Milk. A. Gustav Luebert. (Journ. Amer. Chem. SOL, xxiii., 682.)--The test is made as follows : Five grammes of coarsely-powdered potassium sulphate are placed in a 100 C.C. flask, 5 C.C. of the milk distributed over it by means of a pipette, and then 10 C.C. of concentrated sulphuric acid carefully poured down the side of the flask. The whole is allowed to stand, and if formaldehyde is present the crystals of potassium sulphate will acquire a violet colour in a few minutes, the liquid also gradually becoming coloured. If no formaldehyde is present, the liquid will at once turn brown, rapidly changing to black. The test is sensitive to a dilution of at least 1 part formaldehyde to 250,000 parts milk, and is given even more rapidly by milk which has stood for several hours than by a fresh sample.A. G. L. Detection of Cocoanut Oil in True Butter. I?. Ranwez. (Ann. Pharm., 1901, vii., 241 ; through Chem. Zeit. Rep., 1901,24O.)-Vandam has shown that the amount of acids, soluble in alcohol at 60°, contained in cocoanut oil, is much greater than that in true butter or in margarine. Expressed as c.c.s of decinormal potash, and calculated upon 5 grammes of the sample, five specimens of butter have given 10-3 to 11.1 ; cocoanut oil, 44.2 ; and margarine, 3.6. If the proportions of these acids insoluble in water, and those soluble in alcohol at GO", are expressed in the same manner-e.g., butter, 4.6 to 5.2 ; cocoanut oil, 42-0 ; mmgarine, 3.1, these differences become much larger.Therefore an addition of 12 or 13 per cent. of cocoanut oil to cow's butter would double the amount of water-insoluble acids in the alcohol-soluble acids, while an addition of 25 per cent. thoreof would treble it. F. H. L. The Determination of Starch in Cereals. L. Lindet. ;Journ. Phaym. Chim., 1901, xiv., 397-400.)-1n order to obviate the difficulty of filtration in his method (ANALYST, xxii., 20), and to prevent cellular debris being weighed with the starch, the author proposes the following modification. The starch washings passing through the sieve after the digestion with pepsin and hydrochloric acid are collected in a 500 C.C. conical flask, where the starch is allowed to subside, and is washed once or twice by decantation.As the starch settles but slowly, it is necessary to allow the liquid to stand from twelve to twenty- four hours after each washing, any bacterial action being prevented by the addition of a little formaldehyde. The washed starch is then heated for an hour at 110" C. with 100 C.C. of 0.25, 0.5, or 1 per cent. sulphuric acid, and the resulting saccharified solution neutralized and diluted to 250 C.C. The amount of glucose and of dextrin are then determinedTHE ANALY8T. O9 by reduction with Fehling's solution and polarization, and the original amuunt of starch calculated from the results. When much oil is present in a cereal it is advisable to extract it prior to the digestion with pepsin, since otherwise the starch does not separate well in the decantation.C. A. M. Some Analyses of Bulgarian Buffalo and Sheep Butter, Lard, and Wa1nz;t Oil. N. Petkow. (Zeit. fiir Untcrsuch. der Nahr. Und Genussmittel, 1901, iv., 825, 887.)-The maximum, minimum, and average results of the analyses of samples of buffalo and sheep buttsr are given below. It will be seen that the composition of these does not differ greatly from that of cow's butter, although the Reichert-Meissl figure for buffalo butter is somewhat higher. The average amount of water in the buffalo butters was 14.39 per cent. and in the sheep butters 12.72 per cent. BUFFALO BUTTER (14 samples). Insoluble Free Per Cent. O Burst~n. Specific Reichert- Kott- Gravity Meissl storfer Iodine Acidity, at 100" C. Number.Number. Number. Acids' Maximum Minimum Average.. . Maximum Minimum Average.. . Maximum Minimum Average.. . Maximum Minimum Average.. . ... 0.8700 44.8 40.10 234-7 45.52 ... 0.8680 43.8 30.90 222-5 30.29 ... 0.8692 44-2 34.20 229.0 36.75 SHEEP BUTTER (12 samples). ... 0.8695 45.5 29.37 234.0 38.48 ... 0.8690 42.5 23.21 223.0 29.70 ... 0.8693 44.4 26.68 227.8 35-14 LARD (3 samples). ... 0.861 52.0 0.52 198% 65.56 ... 0.860 51.8 0.55 198.2 65.23 ... 0.860 52.0 0.53 198.4 65.36 WALNUT OIL (5 samples, cold pressed). At 15" C. .,. 0.9260 68.0 - - 148.43 ... 0.9255 67.0 - - 147-92 ... 0.9258 67.7 - - 148.21 87.20 6-13 89-20 3.22 88.19 4.51 89.90 3.21 87-90 0.50 88.50 2-01 96.14 1-08 96.01 1.02 96.08 1.05 - 5.97 - 3.17 - 4-38 w. P. s. Prussic Acid in Sweet Cassava. Carmody.(The Lancet, September, 1900.) -The author confirms the statement of 'Francis (ANALYST, 1877, 4-7) that prussic acid is present in sweet cassava to a considerable,extent. He finds that the prussic acid is not uniformly distributed throughout the tuber, the inner part containing on the average 0.006 per cent., whilst the skin and outer cortical layer contain 0.028 per cent. of HCN. In bitter cassava the prussic acid is uniformly distributed, the average amount being 0.023 per cent. w. P. s.10 THE ANALYST. The Decomposition of Food Materials by Micro-organisms. Part I. ; Fat- consuming Micro-organisms. J. Konig, A. Spieckermann, and W. Bremer. (Zeit. fGr Urttersuch. der Nahr. und Genussmittel, 1901, iv., 721-744, and 769-780.)- Three samples of cottonseed meal were used in the experiments described in this paper.They contained fungus spores, as well as bacteria of the hay and potato species. The fungi only increased in growth when the percentage of water in the meal was not under 14 per cent. From 14 to 30 per cent. of water was most favour- able to the growth of the fungi, whilst with above 30 per cent. the bacteria obtained the upper hand. The mould flora changed with an increase of moisture. Eurotium repens first appeared, soon followed by Eurotium rubru7n; with 20 per cent. of moisture the ‘‘ Oidium ” species of mould-fungi were noticed, and with 25 per cent. Penicillium glauculm. The growth of tbe fungi was always accompanied with a loss of organic matter, but an increase of water. On the appearance of Penicillium glaucum, the fat and non-nitrogenous extractives were rapidly attacked, and also the pentosans to a small extent.A small quantity of proteid matter was converted into water-soluble organic bodies, but no ammonia was formed. The nitrogenous matter was acted on to a small degree with the liberation of nitrogen. The bacteria obtained the carbon they required from the non-nitrogenous extractives (raffinose, etc.) and pentosans, decomposing the fat only to a small extent. On the other hand, the proteids were decomposed with the production of ammonia. Experiments with pure cultures of the fungi on sterilized cottonseed meal, and also on culture media, containing fat, showed the same results as above. From cultures of Aspergillus jlavus and Eurotium reperts on sterilized cotton meal, an enzyme was extracted by means of glycerin, which had the property of forming butyric acid from mono- butyrin. This enzyme did not appear to act on cotton oil, but the fact that the amount of fatty acid increased in the experiments points to some decomposition of the higher glycerides.The fat is apparently for the most part directly converted into carbon dioxide and water by the action of the fungi. w. P. s. Detection of Cherry Juice in Raspberry Juice and Red Wines. X, Windisch. (Zeit. fiir Untersuch. der Nahr. wad Gemmsmittel, 1901, iv., 817-825,)- All cherries examined by the author contained hydrocyanic acid (from amygdalin), This acid is present in the flesh of the cherries as well as in the stones, although in smaller quantity.The fermented juices of cherries, both with and without stones, always contained hydrocyanic acid. The presence of hydrocyanic acid serves as. a means for detecting cherry juice in other juices. The test is applied as follows: 20 to 30 C.C. of the fruit juice are distilled until about 2 C.C. have come over. To the latter is added a drop of guaiacum tincture, together with a drop of dilute copper sulphate solution. The appearance of a blue colour indicates the presence of hydrocyanic acid. The colour is fugitive, and if very faint may be intensified by shaking out with B little chloroform, in which it dissolves. A negative test does not prove the absence of cherry syrup, 8s the original amount of hydrocyanic acid in the cherries may have been very small. w. I?. s.THE ANALYST.11 Estimation of Morphine in Opium by means of Ammoniacrtl Silver Chloride. 42. Reichard. (Chem. Zeit., 1901, xxv., 816.)-If the opium sample exists as an alcoholic solution, it is diluted with three times its volume of water and evaporated t o its original bulk; otherwise, about 2 or 3 granimes of the material are extracted for an hour with ten to twenty times that amount of boiling water, shaking or mechanically agitating the while. The mass is filtered, and the residue washed several times with boiling water. To the filtrate and washings a small excess of ammoniacal silver chloride is added, and the whole is warmed gently. After standing some time, when the precipitate no longer increases and the liquid is clear, the deposit is collected, washed till free from dissolved silver compounds, dried, and ignited in porcelain to give a button of metallic silver.Two atoms of silver correspond with one of morphine. Experiments show that the other opium alkaloids and .constituents do not reduce ammoniacal silver ; but to insure absence of (adventitious) reducing matter, another portion of the sample should be extracted with water, precipitated with ammonia to throw down all the alkaloids, and the filtrate examined for any reducing power, Since the reagent contains excess of ammonia, its first effect is simply to precipitate a11 the alkaloids in the opium, so that the substance on the filter is a mixture of metallic silver with the other opium bases ; but inasmuch as the latter are all destroyed by the ignition, this does not affect the accuracy of the process.F. H. L. The Estimation of Mercury in Antiseptic Solutions. G. Meillbre. (Journ. Pharm. Chim., 1901, xiv., 356-359.)-When the mercury is present in the form of chloride or iodide, it can be extracted quantitatively by shaking the liquid with an excess of eulphuric ether or acetic ether. Thus, 5 C.C. of a solution of mercuric chloride containing 0.0343 gramme of mercury yielded, on evaporation of the ethereal extract, a residue containing 0-0338 gramme of mercury. For determining the mercury in the salt thus isolated, the author precipitates the metal in the free state by means of stannous chloride or magnesium and hydro- chloric acid, etc., and washes and dries the precipitate in a weighed tube, with the aid of centrifugal force. Mercuric cyanide is usually in a sufficiently pure state, and is readily deter- mined in its solution, but the oxycyanide, when properly prepared, is much less soluble. Hence the commercial salt is frequently a mixture in varying proportions of mercuric cyanide and oxycyanide. In various commercial samples the author has found from 76% to 81 per cent. of mercary, as against 85.04 per cent. by theory. The cyanogen can be determined by treating 0.1 gramme of the salt with standard iodine solution, in the presence of an excess of alkali-metal carbonate, and after the lapse of several minutes titrating the liquid with a standard solution of thiosulphate. C. A. M.