Some basic factors in the bleaching of fatty oils

• Published in: Journal of the American Oil Chemists' Society Vol. 41; no. 4; pp. 315 - 321
• Main Author: Rich, A. D.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer‐Verlag 01-04-1964
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1007/BF02667028

The physical and chemical properties of bleach‐ing clay are presented, and the effects of these properties upon its performance in bleaching. Various bleaching effects are described:
Comparison of atomspheric vs. vacuum bleaching, showing the superiority of one or the other depends upon the predominance of oxidative color fading or color fixation/ color formation in the atmospheric bleach.
The log‐log bleach curve of clays carried out to extreme dosage.
Bleaching time‐temp effects on different oils, showing that up to a given time, high temp bleaching gives a lighter color than low temp; however, with increased time the high temp bleached oil darkens rapidly in con‐trast to the low temp oil, which levels out with time.
The effect of adding clay to hot oil vs. ad‐ding it to 舠cold舡 oil, indicating a better bleach when the clay is added to the cold oil, with an explanation for the effect.
Comparison of bleaching by filtration of the oil through a layer of clay against conventional bleaching, indicating superior‐ity for the former.