STUDIES IN CARBOHYDRATES 
MATERIALS, APPARATUS, AND METHODS 
N THE investigations herewith detailed, wheat bread, oyster, soda, and 
Educator crackers, pretzels, matzoth, and .taka-diastase, peas, beans, 
lentils, and a dozen starches were used. 
Acme, Freihofer, Kolb, Jones, and Sharpless breads were examined. All 
loaves were weighed; physical properties—texture, odor, flavor, and color— 
noted for the crust and interior. 
The loaf and crust were crumbled separately and allowed to dry in the 
air. Each sample was powdered by grinding in a coffee-mill and transferred 
to a stoppered bottle. In the case of crackers, preliminary drying was omitted 
as unnecessary. They were powdered and bottled as the bread. In the com- 
position experiments the moisture was determined in the fresh bread, loaf 
and crust, and in the crackers as purchased. 
Acidity is expressed as lactic acid, determined by shaking ro gm. of the 
material with 250 c.c. of distilled water for fifteen minutes, filtering and 
titrating an aliquot portion of the filtrate. A second portion was evaporated 
to dryness in a platinum dish, the residue being the water-soluble material. 
Ash was determined by burning 2 gm. at a very low heat until white. 
Salt was determined by macerating 5 gm. with 20 c.c. of water and titrat- 
ing with silver nitrate, using potassium chromate as indicator. 
Fat was determined by extracting 8 gm. with ether in the usual extraction 
tube for ten hours. 
Nitrogen was determined by the Kjeldahl-Gunning method, using 3 gm., 
and the protein was calculated by the factor 6.25. 
Total carbohydrate was determined by macerating 2.5 gm. in то с.с. of 
water in a mortar, cooling to 10” C., adding 20 c.c. of concentrated hydro- 
chloric acid, previously cooled to 10? C., and allowing the paste to steep for 
thirty minutes at 20° C. The mixture was transferred to a 100 c.c. flask, 5 
c.c. of a 4 per cent. solution of phosphotungstic acid were added, and made 
up to the mark with hydrochloric acid (sp. gr., 1.125), also cooled to 10° C. 
The mixture was well shaken and placed for thirty minutes in a water-bath 
at 20° C. After filtering and allowing to stand for fifteen minutes the filtrate 
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