372 REPORT OF THE BUREAU OP ANIMAL INDUSTRY. 



freshly killed hogs is used, and, as also in the case of the beef fat, 

 scrupulous care is taken that every piece used shall be without taint 

 of any kind. The neutral is not pressed to extract the stearin. As 

 it falls from the melting kettles ^into tanks of strong iced brine 

 placed to receive it, it crystallizes into flakes, white as snow, and ab- 

 solutely without perceptible smell or taste. It remains in these vats 

 about twenty-four^hours, and is then removed and placed on shelves 

 to drain, after which it is ready for use. The object of the process 

 is to obtain a neutral fat melting at butter temperature. 



Most oleomargarine factories are buildings four stories in height. 

 On the upper floor the oleo oil and neutral are melted in separate 

 kettles, at a temperature of about 90 F. The proportion of milk and 

 cream which enters into the product is from 10 to 20 per cent. One 

 of the firms largely engaged in this manufacture in Chicago (Fried- 

 land & Swift) have in their establishment a well-appointed dairy, 

 heated by steam pipes to the required temperature, in which pans of 

 cream and milk are set out to sour, and are afterwards separately 

 churned into butter precisely as in a creamery dairy. The more 

 usual process is for the charge of cream and milk, slightly soured, 

 to be first run into a steam- jacketed churn, fitted with steam paddles, 

 which are agitated until butter begins to form. Then the oleo oil is 

 let down and stirred in by the agitators. After it has been 

 thoroughly mixed the neutral lard is added, and lastly a small quan- 

 tity of best quality of creamery butter, and sufficient annotto (the 

 harmless vegetable coloring used in butter-making) to give the re- 

 quired tint. The temperature during the churning process is care- 

 fully regulated, beginning at 85 F. and running up to 105 F. , and the 

 time occupied varies from twenty-five minutes to an hour and a half. 

 Some manufacturers, in order to soften the granular consistency of 

 the oleo oil, and to give a better texture to the whole product in cold 

 weather, add a certain proportion of refined cotton-seed salad oil. In 

 the higher grades of oleomargarine this result is attained by decreas- 

 ing the proportion of oleo oil, and adding more creamery butter. 



When all the contents of the churn have been thoroughly amal- 



famated they are discharged into vats of chopped ice in the floor 

 elow. The object of this sudden process of cooling is to give a fine 

 grain to the product. The oleomargarine is allowed to remain in these 

 cooling- vats from thirty to forty-eight hours, until completely solid- 

 ified. It is then taken out and placed on wooden trays to drain, and 

 afterwards is salted and thoroughly worked by mechanical rollers, 

 in the same manner as butter, until all the buttermilk and water 

 have been pressed out. It is then cut and weighed and molded into 

 the required shapes, which vary according to the market for which 

 it is intended. After that it is placed on racks in the cooling-room, 

 at a temperature of about 38 F., and there it stays until packed in 

 stamped tubs and boxes, of isizes regulated by the Government, when 

 it is ready for shipment. 



Scrupulous cleanliness is observed in every process of the manu- 

 facture. This is more than a matter of choice; it is a necessity. Any 

 deviation from it would be perceptible in the manufactured article. 

 The kettles, tubs, tanks, molding-boards, and even the floors of the 

 factories are constantly scalded, steamed, and scoured, and kept as 

 clean as the dairy rooms of a model farm. 



Oleomargarine, under ordinary conditions, will keep sweet and free 

 from rancidity for three months, at least ; it has been kept unim- 

 paired much longer. The completed product, as it leaves the factory, 



