XV, I 



Perkins: Rancidity of Coconut Oil 



467 



absorbing oxygen. A sample of oil B which had been sealed 

 and kept in the dark had an iodine number of 6.68. Attention 

 is called to the close correspondence between this figure and 

 the figures given for the OIB series in Table III, showing the 

 remarkable resistance to air and light possessed by the unsat- 

 urated glycerides in this oil. 



Table III. — Rancidity tests on storage samples. 



Sample. 



1 Sd_.. 



2 Sd... 



3 Sd... 



4 Sd... 



5Sd... 



6 Sd... 



1 SI.... 



2 SK... 



3 St ... 



4 SI.... 



5 SI.... 



6 SI— . 



1 Od.__ 



2 Od_._ 



3 Od... 



4 Od.„ 



5 Od... 



6 Od.._ 



1 ... 



2 O! ... 



3 Ol... 



4 Ol — 



5 Ol — 



6 Ol... 



1 OIB.. 



2 OIB- 



3 OIB- 



4 OIB- 



6 OIB- 



6 OIB.. 



Rancidity factorB. 



s, m 



s. i, m, n . 



. rn, n 



1.8 



1, s, m 



1, s, i, m, n — 



Lm 



1, m, n 



a, 8 



a, s, m 



a, b, i, m, n 



a 



a, in 



a. m, n 



a.1, 8 



a, 1, s, m.. — . 



a, 1. s, i. m. n 



a, 1 



a. I, m 



a, 1, m, n_. 



a, I. s 



a, 1. s, m 



a, I, 8, i, m, n 



a, I _ 



a. 1, m 



a, I, m. n 



Acidity (as oleic). 



Original. 



Per 



cent. 

 0.37 

 0.37 

 0.37 

 0.62 

 0.52 

 0.55 



0.37 

 0.37 

 0.37 

 0.52 

 0.52 

 0.55 



0.37 

 0.37 

 0.37 

 0.52 

 0.52 

 0.55 



0.37 

 0.37 

 0.37 

 0.52 

 0.52 

 0.55 



0.1 



0.1 



0.1 ' 



0.1 



0.1 



0.1 



Final. 



Per cent. 

 0.62 

 0.88 

 0.79 

 0.63 

 0.88 

 0.81 



0.66 

 1.09 

 0.85 

 0.64 

 1.03 

 0.76 



0.97 

 1.11 

 0.96 

 0.86 

 0.91 

 1.41 



1.73 



1.84 

 1.74 

 1.55 

 1.56 

 2.15 



0.15 

 0.11 

 0.21 

 0.11 

 0.11 

 0.18 



Differ- 

 ence. 



Per cent. 

 0.25 

 0.51 

 0.42 

 0.11 

 0.36 

 0.26 



0.29 

 0.72 

 0.48 

 0.12 

 0.51 

 0.21 



0.60 

 0.74 

 0.59 

 0.34 

 0.39 

 0.86 



1.4 

 1.5 



1.4 

 1.0 

 1.0 

 1.6 



0.05 

 0.01 

 0.11 

 0.01 

 0.01 

 0.07 



Iodine 

 number. 



6.93 

 6.94 

 6.90 

 6.92 

 6.93 

 6.90 



6.86 

 6.93 

 6.88 

 6.92 

 7.00 

 6.95 



6.24 

 6.07 

 6.76 

 6.66 

 6.32 

 5.63 



5.21 



5.20 

 5.22 

 5.36 

 5.38 



4.97 



6.71 

 6.69 

 6.66 

 6.68 

 6.61 

 6.67 



Fuchsine 

 aldehyde 

 reagent. 



Oxidiza- 

 bility 

 value. 



0.6 

 0.6 

 1.3 

 1.0 

 1.3 

 1.4 



0.7 



0.6 

 0.9 

 0.8 

 0.2 

 0.7 



0. 

 10. 



2. 



3. 



7. 

 16. 



18. 

 17. 

 18. 

 21. 

 20. 

 18. 



0.0 

 1.1 

 0.0 

 0.5 

 1.0 

 1.1 



Odor. 



Fuchsine aldehyde reagent. 10 — Two grams of fuchsine were 

 dissolved in 100 cubic centimeters of cold saturated aqueous 

 solution of sulphur dioxide. This solution was allowed to stand 

 several hours and then diluted to 2,000 cubic centimeters. 



" Mullikin, Samuel Parsons, Identification of Pure Organic Compounds 

 (1905) 15. 



