18 BULLETIN 282, U. S. DEPARTMENT OF AGRICULTURE. 



(3) This change was not so pronounced in the hops kept in open storage, irrespective 

 of treatment at the dry kiln. On comparison, however, the unsulphured hops showed 

 the greatest change. 



(4) The most decided change occurred in the unsulphured hops in cold storage and 

 the least marked change in the sulphured hops in open storage. 



(5) After the fust year the degree of change in all the samples fluctuated with regu- 

 larity from year to year. Taken in the aggregate, the values as determined from year 

 to year indicate most strongly that an extensive rearrangement took place in the soft 

 resins of the hops from the time they were picked until some point was reached between 

 the first and second year of storage. When this point was reached and the rearrange- 

 ment had practically terminated, a gradual increase or decrease could be traced in all 

 the values taken. 



SUMMARY. 



In 1911, material for a comparative study of the soft resins of 

 sulphured and unsulphured hops in both cold and open storage was 

 secured from a hop ranch at Perkins, Cal. The green hops were 

 divided into two lots, one of which was sulphured during the process 

 of drying. The dry sulphured and unsulphured hops were again 

 divided into lots, sealed in tin cans, and shipped to Washington, 

 D. C. On arrival the cans were opened and an analysis made of one 

 lot each of the sulphured and unsulphured hops. The remaining 

 samples were baled in burlap and three samples each of the sulphured 

 and unsulphured hops were placed hi both cold and open storage. 



At the end of the first, second, and third years of storage one 

 sample each of the sulphured and unsulphured hops was withdrawn 

 from both cold and open storage and an analysis made of each. The 

 hops analyzed in 1911 are designated as "original hops," since they 

 approximate more nearly the condition of the samples at the time of 

 drying. 



A physical valuation was placed on the original samples and also 

 on the hops as they were withdrawn from storage from time to time. 

 From these valuations the conclusions are drawn that both sulphuring 

 and cold storage retard changes in the physical characteristics of hops. 

 A combination of the two factors is more effective in retarding these 

 changes than either factor alone. 



Determinations were made of the moisture, the percentage of soft 

 resins, hard resins, and total resins, of the color, odor, and taste of the 

 soft resins, and of the acid, ester, saponification, and iodin values of 

 the soft resins. 



The moisture content in the sulphured and unsulphured hops held 

 in cold storage increased during the first year and then remained 

 practically constant in all the samples throughout the period of 

 storage. The moisture content of the sulphured and unsulphured 

 hops in open storage varied from year to year, according to existing 

 weather conditions. 



