14 



BULLETIN 282, U. S. DEPARTMENT OP AGRICULTURE. 



a study of the ester and acid values, a gradual increase in the saponi- 

 fication value would be expected. This increase was most marked after 

 the first year of storage, and all the samples gradually approached a 

 uniform value. The saponification value of the soft resins from the 

 sulphured hops was slightly higher than the same value in the un- 

 sulphured hops. The increase in the saponification value was most 

 uniform in the hops held in open storage and was most rapid during 

 the third year in the unsulphured hops in cold storage. 



Table X. — Saponification value of the soft resins in the original samples of sulphured 

 and unsulphured hops and in samples Jcept in cold and in open storage. 



Treatment at the kiln. 



Original 



sample, 



1911. 



Cold storage. 



Open storage. 



1912 



1913 



1914 



1912 



1913 



1914 





169.5 

 1S2. 65 



266.5 

 138.5 



278.5 

 163.5 



317 



2S4 



195 

 175.5 



264 



22S. 5 



324 





236 











IODIN VALUE. 











In determining the iodin-absorption value of the soft resins, the 

 method employed was that commonly used in determining this value 

 in fats. The results obtained are shown in Table XI. 



Table XI. — Iodin value of the soft resins in the original samples of sulphured and 

 unsulphured hops and in samples kept in cold and in open storage. 



Treatment at the kiln. 



Original 



sample, 



1911. 



Cold storage. 



Open storage. 





1912 



1913 



1914 



1912 



1913 



1914 





95 

 100 



76 

 72 



144 

 140 



156 



141 



123 

 89 



132 

 143 





156 





153 







The iodin values, as shown in Table XI and in figure 6, became 

 less divergent in the third year of storage. In the soft resins from 

 the sulphured hops in open storage the iodin value gradually increased 

 for each year of storage. In all the other samples it diminished 

 during the first year, rose rapidly during the second year, and in the 

 third year was uniform with that from the sulphured hops in open 

 storage. This indicates a diminution in the unsaturated compounds 

 in the soft resins from the sulphured hops in cold storage and from 

 the unsulphured hops in both cold and open storage and an increase 

 in the unsaturated compounds in sulphured hops in open storage 

 during the first year. It will be noted, however, that after tho com- 

 pletion of the marked readjustment that took place, during the first 

 year of storage, the iodin value of all the samples tended to become 

 uniform, thus indicating that the unsaturated compounds were present 

 in approximately the same proportion in all the soft resins of all the hop 

 samples at some point between the first and the second year of storage. 



