12 BULLETIN 781, U. S. DEPARTMENT OF AGRICULTURE. 



The results of three tests with peach-kernel oil show that the diet 

 as a whole was well assimilated, the digestibility of the different 

 constituents being 83.7 per cent for protein, 91.8 per cent for fat, 

 and 95.7 per cent for carbohydrate. An average of 34 grams of pro- 

 tein, 62 grams of fat, and 375 grams of carbohydrate, which supplied 

 2,200 calories, was eaten per man daily. The subjects all reported 

 that they felt in normal physical condition throughout the test period, 

 which indicated that peach-kernel oil when included as a part of 

 a simple mixed diet was well tolerated. The digestibility of peach- 

 kernel oil alone, 96.6 per cent, may be considered as evidence that 

 this oil is very well assimilated and would prove a valuable food oil. 



PUMPKIN-SEED OIL. 



The oil that is obtained by cold expression of pumpkin seeds is 

 classified as a semidrying oil and is of a slightly greenish-yellow 

 color. In South Russia this oil is prepared on a commercial scale 

 by roasting the pumpkin seeds, after which the oil is hot pressed. 

 Lewkowitsch ^ states that the hot-pressed oil is viscous, of a brownish- 

 green color by transmitted light, and of a deep red color by reflected 

 light. He further states that attempts to bleach and refine hot- 

 pressed pumpkin-seed oil have not met with success. 



While the amount of pumpkin canned at present is not large, both 

 the output of the individual factories and the number of canneries 

 packing pumpkin are increasing and the indications are that eventu- 

 ally the available supply of pumpkin seed will be sufficient to war- 

 rant commercial consideration. 



The pumpkin-seed oil studied in the tests here reported was ob- 

 tained through the courtesy of H. S. Bailey, of the Bureau of 

 Chemistry. It was prepared by cold pressing a supply of pumpkin 

 seeds obtained from a commercial canning establishment. It may be 

 assumed that this oil was very nearly representative of high-grade 

 pumpkin-seed oil of commerce. Since only a very limited supply 

 of pumpkin-seed oil was available, only two tests were possible. The 

 results which were obtained in the^e tests are reported in the tables 

 following : 



1 Chemical Technology and Analysis of Oils, Fats, and Waxes. London : Macmillan 

 & Co. (Ltd.), 1909, VOL 2, p. 124. 



