OLEOMARGARINE. 771 



Glycerides: 



Tributyrin .................................................... C 3 H 5 (C 4 H 7 O. 2 ) 3 



Tripalmitin ................................................. 



Tristearin 



Trioleiu 



Trilinolein ................. . 



( C 4 H 7 3 

 Mixed glyceride of butyric, palmitic, and oleic acids .............. C 3 H 5 



Dr. WILEY. The acid in vinegar is acetic acid, which is the first of 

 these fatty acids, and the others which you see there, of which acetic 

 acid is the type, form the lowest members of this series. Then comes, 

 after acetic acid, butyric acid, which is the chief volatile acid of butter, 

 and gives it its peculiar flavor; while in goat milk the percentages of 

 caproic, caprylic, and capric acids are quite large, and give it that 

 strong, goaty flavor which it has. They are also present in butter, but 

 in lesser quantities. Now, these are the other fatty acids: Laurie, 

 myristic, palmitic, stearic, and arachidic (which is found in peanuts); 

 while the oleic acid series (which is nearly related to them) and linoleic 

 acid (which exists in flaxseed oil) form members of a separate series 

 of acids. 



Before leaving this table, I want to call your attention to the remark- 

 able resemblance between these acids, simply increasing, as they do, in 

 regular order by the addition of a molecule composed of hydrogen and 

 carbon to each one. In the table, "G" mfeans carbon, "H" means 

 hydrogen, and "O w means oxygen. 



Look at acetic acid, which is the acid in vinegar. That has two atoms 

 of carbon, four of hydrogen, and two of oxygen in its molecule. Now, 

 you see, all the acids of that series have absolutely the same amount 

 of oxygen. They all have two atoms of oxygen; but the increase in 

 each case is made by adding two atoms of carbon and four atoms of 

 hydrogen. In other words, if you add C 2 and H 4 to one acid, you get 

 the next. You will see that in every case it is a regular increase from 

 the beginning to the end of the series. If you add C 2 H 4 to acetic acid, 

 for instance, you get butyric acid. Add O 2 H 4 to butyric acid and you 

 get caproic acid, and so on down through the series. They are all 

 related in that step-ladder way, one with another. 



Representative BAILEY. In regular numerical progression t 



Dr. WILEY. In numerical progression. Now, there is no acetic acid 

 in butter; but the next one to acetic acid (the vinegar acid) is butyric 

 acid, which is the chief one of these volatile acids in butter. You see, 

 there is 6.23 per cent of butyric acid in butter. Now, the goaty acids, 

 which are named from the Latin name for u goat," because they exist 

 largely in goat fat, are the caproic, caprylic, and capric acids, the 

 caproic acid being the largest in amount, and the others being present 

 in small quantities. Next comes lauric acid and myristic acid in con- 

 siderable percentage; but the most abundant of them are the oleic, 

 stearic, and palmitic acids belonging to the upper series. The stearic 

 acid of the upper series is the smallest in quantity and the palmitic 

 acid the largest in quantity in butter fat. 



Eepresentative WILLIAMS. Is palmitic acid named from palm oil! 



Dr. WILEY. Yes; palmitic acid exists largely in palm oil; hence the 

 name. Now, so far as wholesomeness is concerned, these bodies bear 

 practically the same relation to the digestive organism, with this excep- 

 tion, that the lower acids are more easily decomposed, and hence, under 

 the influence of the ferments which produce digestion the presumption 

 is that they digest more rapidly. This is exactly what I said in my 



(*189) 



