108 The Philippine Journal of Science xm 



Sample II was sour in odor, No. 19 was a sweet oil, No. 32 

 was smokelike in odor, while No. 50 was lardlike in odor. 



The iodine values of the steam-treated oils are lower in all 

 four cases than are the iodine values of the original oils. Ap- 

 parently the unsaturated compounds are either volatile in the 

 steam or they are partially changed to saturated compounds by 

 the live steam. 



The acetyl values in three cases are lower for the treated oils. 

 The hydroxy compounds appear to be somewhat soluble in the 

 live steam. The higher value in the case of No. 11 probably 

 arises from the hydrolysis of the glyceryl esters of the fatty acids 

 by the live steam. The free fatty acids which are present in com- 

 paratively large quantities in this sample act as accelerators of 

 this hydrolysis of the neutral oil, or the mono- and diglycerides 

 may be further hydrolized to free fatty acid and glycerol and 

 to the monoglyceride and glycerol, respectively. The Reichert 

 Meissl number shows the variation one would expect with the 

 steam treatment of the oils. No difference in its value was 

 found for the sweet and the rancid oils. 



The free fatty acids and their relationship to the rancidity 

 have been already discussed. This constant is included here 

 in order that the acid value for No. 50 might be tabulated. 



The relative values of the soluble fatty acids vary for the orig- 

 inal and treated oils in a manner difficult to explain. Further 

 data will be necessary before any conclusions can be drawn 

 from this constant in regard to the effect of steam distillation. 

 Dakin 16 has shown that when oleic acid is oxidized with hy- 

 drogen peroxide azelaic acid is formed and all fatty acids 

 from formic up to and including stearic are oxidized by mild 

 oxidizing agents. If the formation of rancidity is caused or 

 accompanied by an oxidation, one of the first changes to take 

 place would be the breaking down of the unsaturated acids into 

 simpler acids with an accompanying increase in the value of 

 the soluble fatty acids. Consequently the value of the soluble 

 fatty acids of rancid oils should be greater than the value for 

 the sweet oils. This generalization holds true for the original 

 oils that have been tabulated in Table V. 



The milk from the coconut contains both oxidase- and perox- 

 idaselike enzymes. These enzymes are not found in the pure, 

 fresh coconut meat, and their presence in such meat is probably 

 due to contamination from the milk of the meat. However, 



"Dakin, H. D., Journ. Biol. Chem. (1908), 4, 63 and 237. 



