TRANSACTIONS OF WAGNER 

 3 



STUDIES IN CARBOHYDRATES 



was polarized at 20 C. A comparison was then made with the polarimeter 

 reading for 2.5 gm. of dry starch treated in a like manner. 



Insoluble carbohydrate was determined after extracting the soluble carbo- 

 hydrate by allowing 25 gm. to stand overnight in 100 c.c. of water, filtering 

 washing, and treating the residue in the prescribed manner. The soluble 

 carbohydrate was determined by difference. 



The calorific values per entire loaf and per pound were calculated on the 

 fresh bread and on the crackers as purchased. 



i pound of carbohydrate = 1860 calories 

 i pound of protein = 1860 



i pound of fat = 4220 



Data, other than moisture and fuel value, are expressed on the dry basis. 



In the digestion experiments the water-bath for keeping the mixture at 

 constant temperature was double a one-gallon agate pail on the outside and 

 a two-quart tin pail suspended within. The range of temperature was not 

 more than i C., and the five samples were treated at one time. 



As previously stated, the ferment used was commercial taka-diastase. 

 Four grams were dissolved in 100 c.c. of distilled water, and kept at a temper- 

 ature of 55 C. for one hour, shaking every fifteen minutes. The solution was 

 made fresh every day, and kept in a tightly stopped bottle; exactly 25 c.c. of 

 the extract was added to i gm. of the bread in 50 c.c. of distilled water. The 

 extent of the action of the diastase was determined by the amount of sugar 

 formed, using Fehling's solution. 



With this method the flasks containing the bread (loaf) and the diastase 

 were kept stoppered and shaken every ten minutes. Digestion was allowed 

 to continue for thirty minutes. 



Then the flasks were removed from the water-bath, heated until the 

 contents boiled to stop enzyme action, filtered, the wash-waters added to the 

 solution, and the whole made up to the mark in a 250 c.c. flask. The solution 

 was then tested for sugar by the following modification of a method proposed 

 by Lintner: Into labeled test-tubes, each of 40 c.c. capacity, was run from 

 a pipet i c.c. each of the two parts of Fehling's solution, different amounts of 

 the digestion mixture (i to 5 c.c.), and enough distilled water to make up to 

 15 c.c. The tubes were then plunged together into boiling water and all 

 removed at the end of twenty minutes. 



The amount of the given sugar solution needed to reduce 2 c.c. of Fehling's 



