36o 



Journal of Agricultural Research 



Vol. XIII, No. 7 



According to the tintometer readings, for the last two years (19 15-16), 

 the control, enzym-free, and moisture samples retained the most color; 

 light and light-moisture next; air and air-moisture less; and air-light 

 and air-light-moisture the least color. The organoleptic tests for the 

 entire period rated light, and light-moisture more active than air and 

 air-moisture, but equally effective at the close of the experiment, or 

 nearly so. Differences between organoleptic and tintometer readings 

 are due, partly at least, to the fact that the unaided eye is less sensitive 

 to the yellow than to the darker colors and is unable to differentiate 

 accurately between faint colors, but more particularly to failure in 

 properly coordinating activeness or speed of destruction and effective- 

 ness or completeness of destruction. 



The viscosity of a "fractional" quantity of several of the samples was 

 determined in 191 2 by means of a Redwood viscosimeter. 



Table IV. — Viscosity of the olive oil, igi2 



A 

 F 

 I. 



Conditions of the experiment. 



Control 



Air-light 



Air-light-moisture 



viscosity. 



15-8 



20. 5 



21. 7 



Air-light and air-light-moisture evidently increased the viscosity to a 

 slight extent. 



che;micaiv tests 



The decomposition of the olive oil as affected by air, light, and moisture, 

 singly and in combination, was measured in terms of acid, saponification, 

 and iodin numbers. At the outset the oil seemed to possess a certain 

 resistance to hydrolysis, oxidation, etc., but after it began to break 

 down to any extent, the changes were more rapid. The hydrolytic 

 effect of air, light, and moisture on the glycerids of the oil was measured 

 in terms of acid number, which indicates the amount of free fatty acids 

 produced (Table V). 



Table V. — Acid number of the olive oil 



Conditions of the 

 experiment. 



.as 



o 



Control , 



Enzym-free 



Air 



Light 



Moisture 



Air-light 



Air-moisture 



Light-moisture. . . . 

 Air-light-moisture . 



2. 18 

 2. 18 

 2. 07 

 2. 26 



2-33 



2. 10 



2-35 



2. 46 

 2.42 



-l-o. 19 

 -t-o. 19 



-1-0.08 

 -1-0. 27 

 +0.34 



-l-o. II 

 -f-o. 36 



-1-0.47 

 -1-0.43 



2-55 

 2. 28 

 2. 60 

 2.81 

 3-09 



-1-0.30 



-f-o. 21 



-t-o. 02 



+ 0.39 

 + 0.56 



-l-o. 29 

 -ho. 61 



-1-0.82 



-)-I. 10 



2.28 

 2.03 

 2.54 



2.97 



3-29 

 4.08 



-1-0.48 

 -f-o. 29 

 -ho. 04 

 +0. 55 

 -ho. 94 

 -ho. 79 

 -ho. 98 

 -hi. 30 

 4-2.09 



2.66 

 2-39 

 2. 25 

 2.86 

 3-48 

 3-58 

 3-69 

 4. 01 

 5-88 



-ho. 67 

 -ho. 40 

 -ho. 26 

 -ho. 87 

 -hi. 49 

 -hi. 59 

 -hi. 70 

 -h2. 02 

 +3-89 



2.97 

 2.68 

 2. 60 

 3.06 

 4- IS 

 4.94 



-h .98 

 -h .69 

 -h .61 

 -hi. 07 

 -h2. 16 

 ■95 



4. 60 -h2. 61 

 4.86 -h2. 87 

 8. 09 -h6. 10 



3.00 

 2. 64 

 2.96 

 2-39 

 4- 59 

 6.83 

 5-67 

 5-59 

 12-45 



-hi. 01 

 + .6s 

 + -97 

 -h .40 

 -h2. 60 

 -h4-84 

 -h3-68 

 +3- 60 

 -hio. 46 



