218 Bulletin 230. 



The primary object for which potatoes are produced in the United 

 States is for table consumption. In Germany and in parts of France, 

 on the other hand, they are grown in large quantities for other pur- 

 poses, such as for starch making, from which alcohol may be produced, 

 and for feeding purposes. Hence, from our present point of view 

 the estimate of quality in potatoes might well be based upon their 

 culinary properties; and it is suggested that mealiness in cooking, 

 color and flavor be considered as the principal factors in this estimate. 



The Real Basis of Quality in Potatoes. 



The scope of this bulletin is a study of some of the factors in the 

 growth and development of potatoes which influence their culinar}- 

 quality, special attention being given to their texture when boiled 

 in water. The subject has been very little studied from this point 

 of view. Coudon and Bussard, two French scientists, whose work 

 has already been mentioned, gave the matter some study and pub- 

 lished their conclusions in Annales de la Science Agronomique, 2d 

 series, Vol. I, 1897. Their conception of what constitutes a good 

 potato differs materially from our estimate of quality. They con- 

 sider that the cooking varieties of potatoes from the point of view 

 of their chemical composition, are characterized by: 



(1) Aqueousness; (2) Richness in nitrogenous matter, principally 

 in albuminoids; (3) Relative poorness in starch. 



They further consider that " The resistance to boiling in water . . 

 without breaking down in structure does not (hold) depend, as one 

 might believe, on a high content of pectic bodies, more than on a 

 paucity of starch. This resistance seems due, more or less, in a 

 large measure to the proportion of albuminoids which they contain 

 compared with their starch content. Among the varieties studied 

 in 1895 all those in which the proportion of albuminoids to 100 

 parts of starch fell above 8 . 6 resisted the boiling in water completely, 

 while those falling below that average varied appreciably. Breaking 

 down was complete in those varieties in which the proportion was 

 below 6.6." 



From our own studies and investigations extending over two 

 years, it seems that the culinary and dietetic quality of potatoes is 

 not dependent upon chemical composition so much as it is upon the 

 anatomical (and perhaps physiological) characteristics of the tuber, 

 and the arrangement and distribution of starch and water areas 

 in its substance. The structural characteristic of the tubers is in- 

 fluenced by the*" conditions of the soil, and of the soil and atmospheric 

 climate in which the potatoes grow. 



