648 FOODS AND FOOD ADULTERANTS. 



Seducing sugar. This "was determined by dissolving 1 gram of the sample in 10 

 cc of water. Each cc of the solution contains therefore 0.01 gram of substance 

 This test was carried ont in the usual manner by allowing so much of this sola 

 tion to flow into 10 cc of the Fehliug solution, kept at the boiling-point, until al 

 of the copper had been precipitated as cuprous oxide. 



The end of the test was determined by aid of a ferrocyanide of potassium an< 

 acetic acid solution ; the amount of invert sugar present is found by dividing 500 b; 

 the number of cubic centimeters of saccharine solution used to precipitate all of th 

 copper. This value obtained records the amount of reducing sugar in percentage. 



Water. On the sugar and confection samples the water determinations were mad 

 on 5 grams; in the honey, the sirup, and molasses samples 2 grams were used. 



With all of the confection, honey, sirup, and molasses samples sand had to b 

 mixed, in order to insure a perfect desiccation. The drying was accomplished in a 

 water-jacketed air bath, the water in which was cold at the start, and which wa 

 gradually raised to the boiling point. 



The sugars and confections were dried from three and a half to four hours ; th 

 honey, sirup, and molasses samples received ninety-one consecutive hours' drying ii 

 a fresh-water bath, and were then placed for two to four hours more in a salt-wate 

 bath, there being maintained at a constant temperature of between 102 and 103 C 



Ash. For the determination of the ash there were used of all samples 2.5 grams 

 These were burned off with ether and sulphuric acid, and from the weight fount 

 one-tenth was deducted. The incineration was in every instance made at dull-re( 

 heat in platinum dishes placed within a platinum muffle. 



Coloring matters. The test for coloring matters was applied to the confections 

 Five grains were dissolved in distilled water, made up to 100 cc, and filtered throug! 

 paper or through asbestos. 



In nearly all of the samples the coloring matter was completely soluble in water 

 A portion of the filtrate was evaporated, the residue incinerated, and the ash taken 

 up with distilled water. 



In the very few instances where the coloring matter was not completely soluble in 

 water it was removed from the filter and examined. In some cases copper, lead, an< 

 iron were looked for. 



Matter insoluble in cold water. Five grams of the confection samples were dis 

 solved in cold distilled water, aud the solution made up to 100 cc. The samples wer 

 left in the water for two and a quarter hours, being frequently stirred. The insolu 

 ble matter was then removed by filtration through weighed filters of paper or asbes 

 tos. These, with their contents, were then thoroughly dried at the temperature o 

 boiling water, reweighed, and the amount of insoluble matter calculated and ro 

 corded in percentage. 



Tin. This metal was tested for in all of the sirup and molasses samples. About 5 

 grams of the sample were incinerated, the ash was boiled with hydrochloric acid 

 and sulphuretted hydrogen was passed into the solution. When a precipitate was 

 formed this was separated by filtration and further examined for tin by attempted 

 reduction to the metallic state. 



RECORD OF ANALYSES. 



The total number of samples analyzed was 178. 



There were required : 



Samples. 



Group I. Sugars 50 



II. Sirups and molasses 50 



III. Honeys 50 



IV. Confections 25 



In addition to these, two samples of undoubtedly genuine honey and one sampl 

 of "commercial dextrin " were examined for comparison with the samples purchased 



Special tests, whenever made, and such comments as seemed called for, will b 

 found appended to the full record of analysis of each group. 



