FREE INSTITUTE OF SCIENCE 



STUDIES IN CARBOHYDRATES 



as served for food, and in petits pois, canned. In every case the starch granules 

 were found to be entirely gelatinized, either swollen or broken. 



TABLE 3 STARCH IN BREAD AND CRACKERS. 



WITH POLARIZER 



SOURCE 



STRUCTURE 



GRANULES 



Without Selenite With Sclenite 



5. GELATINIZATION POINTS. For these experiments a triple water-bath 

 of three beakers was used. The heat was applied gradually, stirring the paste 

 constantly. One gram of the starch was made into a paste with 100 c.c. of 

 distilled water. A drop of the paste was removed at each degree and viewed 

 with the microscope. The point at which double refraction disappeared in 

 the majority of the granules was taken as the point of gelatinization. (See 

 Table 4.) 



TABLE 4 GELATINIZATION POINTS OF FREE STARCH. 



Potato (dried) 6s-66 



Potato (raw) s8-59 



Maranta 7O-7i 



Sago 7-7i. 



Tapioca uncertain 



Sweet Potato ... 7-7i 



Corn 7-7i 



Wheat (dried) S9- 



Wheat (flour) 59-6o 



Pea and bean 63 "-64 



Gelatinization of Pea, Bean, and Lentil Starcltes. In these experiments the 

 conditions were as above, except that the paste was made with i gram of raw 



