Identification, Specific rotation, Chloride, Calcium, Sulfate, and Heavy metals
Transfer about 20 g, accurately weighed, to a 100-mL volumetric flask, add 80 mL of water, shake to dissolve the sucrose, then add water to volume, and mix. Separate the solubilized sucrose from the insoluble starch component by filtration until the filtrate is sparkling clear. Use the insoluble portion for the
Identification test, and use the freshly prepared, clear filtrate for the other tests that follow.
Identification
A water slurry of the insoluble portion responds to Identification test B under Starch.
Specific rotation 781
: not less than +62.6
, determined on a portion of the filtrate, corresponding to not less than 95.0% of C
12H
22O
11, calculated on the dried basis.
Chloride 221
A 10-mL portion of the filtrate shows no more chloride than corresponds to 0.40 mL of 0.020 N hydrochloric acid (0.014%).
Sulfate 221
A 25-mL portion of the filtrate shows no more sulfate than corresponds to 0.30 mL of 0.020 N sulfuric acid (0.006%).
Heavy metals 231
To 20 mL of the filtrate add 4 mL of water and 1 mL of 0.1 N hydrochloric acid: the limit is 5 ppm.