774 OLEOMABG ARTNTB. 



is that it is made uniform. But the point is not a good one, because 

 the people who color butter do not color it uniformly. We find the most 

 remarkable variations in color. Some of it is almost red and, on the 

 other hand, there [exhibiting a piece of silk] is a pale yellow, closely 

 resembling the natural tint of butter. 



Now, these colors are all coal-tar dyes, everyone of them. The 

 vegetable dyes, like annotto, have almost ceased to be used in coloring 

 butter. You may find them in some localities. Some States require 

 that butter be colored with annotto and not with coal tar dyes, but 

 everyone of these is a coal tar dye, and you will see by the variations 

 in tint (they do not show very well in artificial light) that the amount 

 of color in the samples was very different. The same amount of material 

 was used in each case. Now, compare these two [exhibiting samples], 

 That [indicating] was a very light-colored sample; this [indicating] 

 was a very heavily colored sample. 



Dr. Wiley at this point submitted the following statement: 



COLORING MATTERS USED FOB COLORING BUTTER AND ITS IMITATIONS. 



Annotto, the principal vegetable dye used, is mainly composed, of the pulp sur- 

 rounding the fruit Bixa orellana growing in the East and West Indies and South 

 America. Allen states that two different kinds reach England, namely, the Spanish 

 anuotto, imported from Brazil, and the flag or French annotto, which comes from 

 Cayenne. 



Annotto contains two yellow coloring matters which have been given names 

 derived from the botanical names of the plants. 



Bixin, C^HruOs, is one of these, but its properties and chemical relationships have 

 been imperfectly studied. When separated in the form of its soda salt it has a 

 reddish color. 



Olellin is described as yellow and soluble in water and alcohol. These two color- 

 ing matters combined, in annotto, give the substance its characteristic orange-yellow 

 color. 



Coal-tar dyes. When diazobenzene-sulphonic acid acts on amids, with an alkaline 

 solution of phenols, a series of coloring matters is obtained ranging from yellow to 

 deep orange or red. These dyes are called tropseolins, because the shades of color 

 they produce resemble those of the nasturtium flower (Tropceolum magnus). They 

 usually occur in commerce as soda salts and are distinguished according to their 

 shades, tropsBolin Y, being the most yellow, and the tropseolin 0, 00, and so on, as the 

 shades become redder. The shade of the color becomes redder by the substitution 

 of toluene, xylene, or cnmene for benzene. 



Two of these dyes which have been used for coloring foods are the acid or fast 

 yellow and the orange yellow or orange G. 



The acid yellow, or the fast yellow, is the soda salt of amido-azobenzene sul- 

 phonic acid, represented by the formula: 



CH 4 (S03Na). N:N. C 6 H 4 .NH 2 . 



Orange G is sodium salt of benzene azobetauaphtol-disulphonic acid, having the 

 formula: 



This class of dyes is also known as sulphonated-azo dyes. 



Victoria yellow has also been reported as a coloring material for butter. This 

 substance is a mixture of the sodium salts of the dinitro-ortho and dinitro-para- 

 cresol C 6 H 2 (CH 3 ).(NO 3 ) 2 .ONa. 



.Representative WILLIAMS. Do you get the colors in these samples 

 from butter? 



Dr. WILEY. From butter and oleomargarine, indiscriminately. 



Eepresentative HENRY. Are we to understand that aniline dyes are 

 used in coloring oleomargarine and butter? 



Dr. WILEY. Yes, sir ; almost exclusively. 



Eepresentative HENRY. I supposed that annotto was the coloring 

 matter used. 



(*192) 



