ABSORPTION OF WATER BY GLUTEN OF WHEATS. 127 
Bancroft. They were examined for the following points: (1) 
strength, (2) gluten-content, (3) proportion of glutenin and gliadin 
in the gluten, (4) physical nature of gluten. 
The strength is estimated by running water from a graduated 
burette upon a weighed quantity of flour until a dough of a given 
consistency is obtained. This consistency is such that it can be 
drawn out into long threads and at the same time adheres to the 
palm of the hand when pressed. 
The gluten was determined by making ten grammes of flour 
into a dough with water, allowing the mass to stand for one hour 
and removing the starch by working the ball between the fingers 
in a glass mortar under a running tap. The gluten thus obtained 
was washed slightly with a definite quantity of ether, introduced 
into a weighed dish, weighed when wet and again weighed after 
drying in the air oven at 100° C. to constant weight. In order to 
be sure that the starch is entirely removed from the dough, it is 
usually stated in printed directions for gluten estimation that the 
gluten should be squeezed until a few drops of iodine added to the 
wash-water fail to produce the characteristic blue colouration. 
As a matter of fact, although very small traces of iodine can be 
easily detected by the addition of boiled starch, it requires an 
appreciable quantity of cold, unboiled starch to strike an immediate 
blue colour with iodine solution. My experience is that the water 
is rendered turbid from the separation of starch long after the 
addition of iodine has ceased to produce an immediate colour- 
ation. The glutens in these experiments were always washed 
‘until they imparted only the slightest cloudiness to the wash-water. 
The determinations of the glutenin and gliadin in the gluten 
Were made according to the method adopted by Messrs. Osborne 
and Voorhees. Fifty grammes of flour were made into a dough 
with water, and allowed to stand for one hour, the gluten was 
extracted in the manner above described, and the wet gluten 
Weighed as a check upon the previous determination. The still 
Moist gluten was then cut up into very small pieces ‘and intro; 
into a flask containing 300 ce. of seventy per cent. aleohol. a - 
