Jan. is, 1921 Tubers, Skins, and Sprouts of Potatoes 631 



Solids. — The solids of the young sprouts of the Green Mountain and 

 Irish Cobbler varieties, samples 1, 4, 7, and 13, were exceedingly uniform, 

 notwithstanding variations in the water content of the tubers. The 

 moisture content of the sprouts seemed to be maintained at the expense 

 of the tubers. The Rural New Yorker sprouts, sample 10, contained 

 more solids than the other young sprouts. The older, partly dried 

 sprouts, samples 16, 17, and 20, were highest in solids. The moisture 

 content of the different varieties of tubers decreased with the period of 

 standing in the laboratory. 



Ash. — The important feature of the ash analyses was the high per- 

 centage of ash in the sprouts as compared with that in the tubers, made 

 more evident on calculating the results to a moisture-free basis. The 

 skins showed a higher percentage of ash than the tubers. The sprouts 

 showed a selective action and withdrew the ash from the tubers in a 

 greater proportion* than it originally existed in them, so that the per- 

 centage of ash in the solids was nearly twice as high for the sprouts as 

 for the tubers. A higher percentage of ash was found in the old than in 

 the young sprouts and tubers. 



Phosphoric acid (p 2 o 5 ).— The phosphoric acid content of the sprouts 

 was greater than that of the skins or tubers. In the solids of the sprouts 

 it averaged 1.81 per cent and was less than 1 per cent for the skins and 

 tubers. In the ash of the sprouts it varied from 20 to 30 per cent, while 

 it was less than 20 per cent in the ash of the tubers and skins. From 60 

 to 76 per cent of the total phosphoric acid content of the young sprouts 

 was water-soluble as compared with but 50 to 60 per cent of the phos- 

 phoric acid content of the skins and tubers. Somewhat less phosphoric 

 acid was water-soluble in the older sprouts and tubers than in the younger 

 samples. 



Nitrogen. — The nitrogen content of the sprouts was apparently 

 uniformly maintained. In the five samples of young sprouts examined 

 (No. 1, 4, 7, 10, and 13) approximately 0.75 per cent of nitrogen was 

 found. The older sprouts contained from 1.10 to 1.27 per cent nitrogen. 

 The different varieties of sprouts showed a uniform percentage of the 

 total nitrogen, both as protein nitrogen and as amid and monoamino 

 nitrogen. The amid and monoamino nitrogen formed about 40 per 

 cent and the diamino and other basic nitrogen formed less than 10 per 

 cent of the total nitrogen of the sprouts. A higher percentage of amid 

 and monoamino nitrogen was found in the older Green Mountain sprouts 

 (samples 16 and 17) than in the younger Green Mountain sprouts (sam- 

 ples 1 and 4). The sprouts contained a lower percentage of total nitrogen 

 in the form of coagulable protein but a higher percentage as total protein 

 than did the tubers. The younger sprouts also contained a lower per- 

 centage of the total nitrogen as amid and monoamino nitrogen and of 

 diamino and other base nitrogen than did the tubers. Based on the 



