?^EW York Agriculturat, Experiment Station. 139 



Experience since then has shown that phytin may be boiled for 

 hours in dilute hydrochloric or sulphuric acid without suffering 

 marked decomposition. In fact it may be boiled for days with 30 

 per ct. sulphuric acid without a determinable quantity of inosite 

 being formed. This seemed strange as various other investigators 

 have emphasized the fact that phytin is very easily hydrolyzed and 

 that even in water it suffers a more or less rapid decomposition. 

 ^.,The action of nitric acid seems to cause a more rapid decomposi- 

 tion; for even the purest phytin when warmed in dilute nitric acid 

 solution with ammonium molybdate gives very quickly the char- 

 acteristic yellow precipitate of ammonium-phosphomolybdate. 

 Several days, however, are required to cause complete decomposition 

 in dilute nitric acid solution at a temperature of 60°-70° C. Quanti- 

 tative experiments to measure the rate of decomposition have not 

 been carried out, but it could very easily be done as the change is 

 very slow. 



The following will illustrate this point: 



In an analysis of two different phytin preparations the substance 

 was boiled with concentrated nitric acid under occasional additions 

 of concentrated hydrochloric acid for about half an hour. At the 

 end of this time the organic matter was apparently destroyed, as 

 the solution was practically colorless. The phosphorus was deter- 

 mined in this solution by the usual molybdate method. After 

 keeping at a temperature of 60° C. for one hour the precipitate was 

 filtered off and the filtrate again warmed on the water-bath for 

 another hour. A new portion of the yellow precipitate had then 

 formed which was removed by filtration and the filtrate again warmed 

 on the water-bath. A yellow precipitate continued to form slowly 

 but continuously for two days when the experiment was discontinued. 

 During this time the water lost by evaporation was replaced from 

 time to time and small quantities of nitric acid were also added. 

 The phosphorus determined in the first precipitate and in that which 

 formed during the first day amounted to only 9.92 and 10.25 per ct., 

 whereas when determined after first destroying the organic matter 

 by the Neumann method 14.42 and 15.23 per ct. respectively were 

 found. 



In another case 100 gm. of calcium phytate was boiled under a 

 reflux condenser with about 300 cc. of 30 per ct. sulphuric acid con- 

 tinuously for one day; over night it was heated on the water-bath 

 and the next day the boiling was continued all day. After precipi- 

 tating with excess of barium hydroxide, thorough washing in hot 

 water, removal of excess of barium by carbon dioxide and evaporat- 

 ing on the water-bath, no inosite could be found in the slight residue 

 which remained. 



To determine if the phytin molecule suffered any partial decompo- 

 sition on boiling with dilute acids, 1 gm. of phytic acid, dissolved 



