Salad oils. Olive, peanut, sunflower, and cotton-seed oils are all 

 used extensively under their own names as foods, and no less than 15 

 oils are used as salad oil or to adulterate olive oil. The sale' of a 

 cheaper for a more expensive oil must be regarded as fraudulent 



CASE 4. 



One of the important questions in connection with the preparation 

 of foods is the extent to which foreign coloring matters may be legiti- 

 mately employed. In most European countries it is forbidden to color 

 artificially any substance which has a distinct color of its own; for 

 instance, wine and fruit products must be sold without the addition 

 of any foreign coloring matter. At the same time all countries per- 

 mit the addition of some harmless colors, often specified by name, to 

 foods and especially confections which are themselves colorless, but 

 are ordinarily artificially colored. In some cases colors whose use 

 with foods is permitted are not only specified by name, but the method 

 by which such colors may be manufactured is given. This is done to 

 exclude the use of coloring matters in whose preparation poisonous 

 substances, such as arsenic, are employed. The fact that some of our 

 common articles of food are often artificially colored at the present 

 time is shown by the dyed fabrics displayed in the top of the three 

 cases. 



Heavy metals. The use of tin cans as hermetically sealed recep- 

 tacles for food has been of incalculable benefit in cheapening almost 

 every article of food and prolonging the season of consumption for 

 those which otherwise could be had only a comparatively short time. 

 At the same time it must not be forgotten that an appreciable amount 

 of heavy metals is often dissolved by the more acid varieties of food. 

 The amount that is so dissolved depends on the age of the sample, the 

 grade of tin plate employed, and the method by which the can was 

 manufactured. Tin plate containing a large amount of lead is much 

 more readily attacked than plate which is nearly free from lead. The 

 plate which is manufactured by the oil process is more resistant to 

 acids than that made by the acid process. Cans in whose manufac- 

 ture zinc chlorid is used, often retain that salt between the seams, to 

 be given up to the contents of the can. It is fortunate that the method 

 of soldering with oil and resin is now usually employed. 



Fruit products. On the fourth shelf of this case is given an inter- 

 esting collection of jelly and jam samples. The forms of adultera- 

 tion to which this class of foods is subject are well indicated on the 

 labels. This exhibit includes pure fruit preparations and products 

 thickened with starch, sweetened with glucose and saccharin, pre- 

 served with salicylic acid, benzoic acid, etc. , and artificially colored. 

 A favorite practice is the preparation of jam from the refuse pulp of 

 jelly manufacture. A sample of raspberry seeds found in "currant 

 jam " is shown on the shelf above. The prices paid for these samples 



