





SOFT RESINS IN SULPHURED AND UNSULPHURED HOPS. Hot: 
All the samples had an extremely bitter taste, manifested strongly 
at the base of the tongue when a minute particle of the soft resin was 
held in the mouth for a few seconds. 
The color, odor, and taste, which appeal solely to the senses, are of 
relatively small importance in this investigation. As shown in Table 
VIII, the color of the soft resins in all cases became darker with the 
age of the sample examined; the odor became very disagreeable with 
the decrease of the soft resins and the taste at all times remained very 
bitter. 
- The soft resins are fluid in nature, and during the first two years of 
storage all were of the same consistency. Those extracted in 1914 
were more solid and had the consistency of a thick sirup. Owing to 
their nature, the specific gravity of these resins could not be deter- 
mined with accuracy. 
ACID AND ESTER VALUES. 
The determination of the free acidity or acid value of the soft 
resins was carried out as follows: A small quantity of weighed soft 
resin was taken up in 2 c. c. of standardized alcoholic potassium 
hydroxid and the excess potassium hydroxid titrated back with N/10 
hydrochloric acid. The acid value represents the number of milli- 
grams of potassium hydroxid necessary to completely neutralize the 
free acids in {i gram of the soft resins. 
In determining the ester value of the soft resins a weighed portion 
was taken up in standardized alcoholic potassium hydroxid and 
allowed to stand 24 hours in the cold. Complete saponification took 
place in that length of time. The excess alkali was titrated back 
with N/10 hydrochloric acid and the saponification value calculated. 
This value, minus the acid value, gives the ester value of the soft 
resins and represents the number of milligrams of potassium hydroxid 
necessary to completely saponify all the combined acids in 1 gram 
of the soft resins. The changes observed in the acid and ester values 
are shown in Table IX. 
‘TasiE [X.—Acid and ester values of the soft resins in the original samples of sulphured 
and unsulphured hops and in samples kept in cold and in open storage. 

hae Cold storage. Open storage. 
Original 
Treatment at the kiln, sample, 
Tele 1912 1913 1914 1912 1913 1914 
Acid value: 
Sullphiredias ss ees see eee 71.80 97.00 87.50 80.7 W250 61.50 47.0 
Unsulphuned 2.3). 7345222. 60. 87 67.00 76. 50 76.2 52.0 70.00 77.6 
Ester value: 
Sulphured. .... Fs ae ea ee 97.7 169.5 191.1 226.3 122.5 202.5 271.0 
Unsulphured...-...-----... ) 121.78 71.5 87.0 207.8 123.5 158.0 158.4 


