May 13, 1918 



Stability of Olive Oil 



361 



The control samples (the basis for comparison) hydrolyzed a little 

 more than the enzym-free, although the differences were slight. 



Neither air nor light showed any appreciable action. 



Moisture was moderately active and gradually effected a noticeable 

 amount of hydrolysis. 



Air-moisture and light-moisture were rather more effective than 

 moisture, although the influence of the air or of the light must have been 

 secondary. 



Air-light was inactive for two years ; then it began to affect hydrolysis 

 and eventually exceeded air-moisture and light-moisture, probably 

 due to the impossibility of entirely excluding moisture under the con- 

 ditions of operation. 



Air-light-moisture was the first .to effect an appreciable amount of 

 hydrolysis and greatly exceeded all others at the close. 



Moisture effected considerable hydrolysis; air-moisture and light- 

 moisture caused an additional amount; air-light, probably assisted by 

 some moisture, still more, and air-light-moisture was the most active 

 and effective. Moisture was the essential factor although air and light 

 together greatly accelerated it. 



The decomposition of unsaturated acids of olive oil as effected by 

 air, light, and moisture may be measured in a degree by the increase in 

 the saponification number which indicates the amount of fatty acid of high 

 molecular weight converted into acids of lower molecular weight 

 (Table VI). 



Tabi^E VI. — Saponification number of the olive oil 



The control, enzym-free, light, moisture, and light-moisture samples 

 were not affected in total alkali-consuming power. Air and air-moisture 

 caused a like increase in saponification number. 



Air-light and air-light-moisture effected a greater increase and of like 

 amount. Air was undoubtedly the principal factor, although greatly 

 intensified by light. 

 49386°— 18 2 



