SOAPS AND PROTEINS 



PART ONE 

 THE COLLOID-<H t:\IISTRY OF SOAPS 



I 



SOAP MAKING 

 1. Introduction 



I r there are included in the definition of soap all those com- 

 pounds which are formed when a metallic base (including ammo- 

 nium) is united with a fatty acid radical, any effort to emphasize 

 their w i< 1< i n i ix>rtance is largely superfluous. Not only do various 

 soaps appear, change and then disappear in living animal and 

 plant cells un<l<T various circumstances, not only do they con- 

 stitute, from both a qualitative and a quantitative viewpoint, 

 one of the chief interests of theoretical and practical chemists, 

 l>ut tlu-ir existence, availability and properties have much to do 

 wit 1 1 the very esthetics of our existence, from clean clothes to the 

 fine arts. 



The making of soap even when carried out in ton lots by 

 the modern manufacturer do- nut in our day differ materially 

 from the methods employed by the pristine housewife Fats " 

 and " oils " are still stirred or l-.il. -.1 in a kettle with a can-tic 

 alkali of some sort. The modem concept of what happens under 

 i instances may be said to date from * i \\ln in 



1815 showed that "fats" and oils," ul.rtt.. i . t , ani- 



mal origin, are compound- i uith alcohol, usually the 



: .-iicni.ui. glycerin \vi..-n -uch com|x.unds (esters, in 



other words) are treated with an alkali, double decomposition 

 the metallic radical uniting with the fatty acids contained 



* 



