16 



boiling solutions; nitrogenous bodies precipitated by Stutter's reagent, 

 and nitrogen as ammonia or its compounds. The methods used in 

 making these determinations in broths were similar to those 

 described above for their determination in the cold-water extracts. 



OBJECT AND PLAN OF THE COOKING EXPERIMENTS. 



The object of the experiments here reported, expressed briefly and 

 concisely, was to study: (1) the losses resulting from different proc- 

 esses of cooking; (2) the influence of cooking on the composition and 

 nutritive value of meats; (3) the nature of the changes in composition 

 resulting when meat is cooked by diflferent methods; and (4) the 

 nature of the water extracts of raw and cooked meats. 



In planning the work it was naturally found that the results of one 

 experiment might help toward the solution of several of these prob- 

 lems, and the question of their classification was thereby rendered 

 complex. For instance, the main purpose of Series VIII was to test 

 the difierences between the changes occurring in difl[erent cuts of 

 meat all cooked bj^ the same method, and in the first three experi- 

 ments (Nos. 121-123) three different cuts of beef were boiled in 

 exactly similar ways. But in the fourth experiment (No. 124) the 

 purpose was to study the difl'erences produced bj^ diflerent methods 

 of cooking on the same cut, and a piece of meat like that boiled in 

 experiment No. 123 was pan broiled. Thus experiment No. 123 

 really belongs to two separate series, but for convenience both are 

 included in one series. The classification finally adopted is based on 

 the kind of meat and the method of cooking rather than upon chrono- 

 logical sequence. If the results of any individual experiment can 

 advantageousl}^ be used in connection with another series, reference 

 can be made to it by number, as will be done in later sections of this 

 bulletin. 



Although the method of cooking is not the most important feature 

 of all these experiments, it is nevertheless one from which many sig- 

 nificant deductions can be drawn. Boiling, pan broiling, roasting, 

 sauteing, frying, gas broiling, and pot roasting were the methods 

 employed. They were essentially the same as those described in a 

 previous bulletin of this Ofiice," any minor variations being given 

 with the individual experiments. In experiments Nos. 119, 124, 142, 

 and 151 the samples were pan broiled; in Nos. 120, 147, and 156 they 

 were roasted; in Nos. 141 and 150, sauteed; in No. 143, fried; in No. 

 152, gas broiled; and in Nos. 146 and 155, pot roasted. In the 

 remaining experiments (Nos. 107-118,121-123, 125, 126, 131-140,144, 

 145, 153, and 154) the meats were cooked by boiling, and a detailed 

 description of this method is here given, partly to explain the somewhat 



»TJ. S. Dept. Agr., Oflace of Experiment tStatioue Bui. No. 141. 



