174 



Kansas Academy of Science. 



To 5 cc. of starch solution in a 100 cc. flask add 5 cc. of a 

 5 percent solution of potassium iodide and 20 cc. of N/500 

 solution of iodine (in 5 percent potassium iodide solution). 

 Stopper the flask, shake and let stand over night. Filter off 

 the precipitated starch iodide and wash the precipitate 

 thoroughly with 5 percent potassium iodide solution. Titrate 

 the filtrate and washings with N/500 sodium thiosulphate 

 solution, with the addition of some starch solution as indicator. 

 Run controls using the same amounts of reagents, but omit- 

 ting the starch. 



Some of the results obtained are tabulated as follows: 



The applicability of the method to the determination of 

 starch in various food products has not yet been determined. 



University of Kansas, Lawrence. 



