METHODS OF MANUFACTURING POTATO CHIPS. 7 



HANDLING THE FAT IN MAKING CHIPS. 



If the sliced potatoes are put into oil which is at a low temperature, 

 they take a long time to fry and absorb so much grease that they are 

 both soggy and unpalatable. Moreover, the more grease consumed in 

 frying, the greater the expense of the product. The aim of the hot- 

 water bath in Miss Farmer's 4 recipe was to coagulate the protein in 

 the potatoes, thus searing the surface and making it impossible for 

 much grease to soak in. The same result may be attained by heating 

 the oil to a point just below smoking before the slices are put in. 

 The higher the temperature that can be maintained, the sooner the 

 surface of the potato will be crusted over and the less oil will pene- 

 trate. The water on the raw sliced potatoes and the temperature of 

 the inner fiying basket itself will lower the initial temperature of the 



Pic. 4.-- Weighing- the slices of potatoes to determine tbe total loss in peeling and slicing. 



oil, and it will take several minutes for the water to boil away and the 

 fat to regain the heat it lost. Fats do not " boil." It is the water in 

 the oil that makes it bubble when heated, and until this has been 

 changed to steam and evaporated the temperature of the fat can not 

 be raised much above 100° C. (212° F.). The hotter the initial tem- 

 perature of the oil, the more quickly the water will be boiled away. 

 A- the water evaporates, the oil becomes still and the temperature in- 

 creases rapidly. It should be reheated after each batch of chips is re- 

 moved. The only certain laboratory method of determining the tem- 

 perature of the fat is to suspend a thermometer in the center of the 

 pan. 



1 i 'armer, i aooie Merrll i. op. clt. 



