SPICES AND CONDIMENTS. 167 



The method of Lenz is described under pepper and its composition. 

 The conditions which we have found most desirable are as follows : 



The 2 to 5 grams of the material, usually 4, which should pass an 80- 

 mesh sieve, must be extracted with strong alcohol and with cold water 

 for some time to remove substances not starch which might be acted on 

 by the acid or reduce Fehling's solution. Then, without drying, it is 

 washed off the filter into an Erlenmeyer flask with about 175 c. c. of 

 water and enough strong C. P. hydrochloric acid added, about 25 c. 

 c., to make the liquid 4 to 5 per cent, of acid gas. The flask is then 

 supplied with a condenser and boiled for four hours, or the liquid may 

 be put in a patent rubber-stoppered beer bottle and digested in a steam 

 bath ; but the latter method is not as certain. After the boiling and 

 cooling, the residue is filtered out, the liquid accurately neutralized 

 with sodic hydrate and made up to 500 c. c. It is then titrated as 

 usually, and can be calculated to glucose or starch on any basis desired. 

 Thorough previous extraction and uninterrupted boiling are the two 

 most important conditions. Without extraction the results are most 

 uncertain and unreliable. 



Determination of tannin. The amount of tannin in certain spices, such 

 as cloves and allspice, is quite constant when they are of good quality. 

 Dr. Ellis of Toronto has therefore recommended this as a good means of 

 detecting adulteration in these spices. He has published as yet noth- 

 ing in regard to his methods of application. In oui experiments it has 

 been found to be of some value, but that it is hardly worth while as a 

 mere aid to the detection of adulteration to go so far as the actual de- 

 termination of tannin, it being quite sufficient to determine the amount 

 of material oxidizable with permanganate which is extracted by water 

 after the careful removal of the oil, &c., by ether. This avoids the 

 tedious use of hide powder, or glue, and furnishes results which are rel- 

 atively of the same value. 



The analyst should therefore prepare himself for carrying out the 

 first part of the modified Loweuthal process, as it is described in Sutton,* 

 and more elaborately in the Berichte liber die Yerhaudlungen der Com- 

 mission zur Bestellung einer einheitliche Methode der Gerbstoffbe- 

 stimmung, and in Anuales de la Science agronomique, Tome 1, 1886. 



Particular pains should be taken to secure a good article of indigo 

 carmine, as without this the results are unreliable. That recommended 

 by Schroder is manufactured by Gehe & Co., of Dresden, and is known 

 as Carminum cceruleum. It should be imported for use. 



Without going into particulars as to the reagents employed in the 

 process, which are probably familiar to all, a few words of caution as 



detail of manipulation will be of value. 



As has been said, preliminary extraction of the material with Squibbs 

 best ether is necessary to remove oil and other substances not tannin, 

 on which the permanganate may act. Ordinary ether will not answer, 



* Sutton, Volumetric Analysis, 3d edition, pp. 276. 



