XXIV. METHODS FOE THE ANALYSIS OF SPICES. 



CHEMICAL EXAMINATION. 

 1. Preparation of Sample. 



Grind the sample until it will pass through a sieve having round holes 1 mm 

 in diameter. For the determination of starch in pepper, by the diastase method, 

 reduce a portion of the sample to an impalpable powder by grinding it in a 

 mortar. 



2. Moisture. 



Dry 2 grams at 110 C. to constant weight. From the resulting loss in 

 weight subtract the amount of volatile ether extract determined as in para- 

 graph 9, page 163. 



3. Ash. 



Determine as directed under " VI. General Methods," page 38. If calcium 

 carbonate be present, care must be taken to burn the material, and also the 

 residue after exhaustion with water, at a heat below redness, thus avoiding loss 

 of the carbonic acid of the carbonate. 



4. Soluble Ash. 



Determine as directed under " X. Saccharine Products," section 3 (c), page 68. 

 5. Ash Insoluble in Acid. 



Incinerate 2 grams of the sample as directed under section 3, boil with 25 cc 

 of 10 per cent hydrochloric acid (sp. gr. 1.050) for five minutes, collect the 

 insoluble matter in a gooch, wash with hot water, ignite, and weigh. 



6. Lime in Ash. 



Determine as directed under " XXVI. Baking Powder," etc., on page 178. 



7. Nitrogen. 



Determine as directed under " VI. General Methods," on page 5, except in 

 the case of pepper, when the Gunning-Arnold method should be used, as follows: 



QUNNING-ABNOLD METHOD. 



(For black and white pepper.) 



Owing to the presence of piperine the Gunning-Arnold method <* must be 

 used to determine nitrogen In both black and white pepper. Mix 1 gram of the 



Zts. anal. Chem., 1892, 81 : 525 ; Conn. Agr. Eiper. Stat. Kept., 1898, p. 190. 

 162 



