PRACTICAL ORGANIC CHEMISTRY ptyalin to function in the stomach for about half an hour after the ingestion of food. Ptyalin works only in the presence of electrolytes, the chloride ion being the most effective. Warm about ioo ml. of distilled water in a beaker to about 40° and with a portion of this thoroughly rinse out the mouth and reject the liquid. Again introduce about 20 ml. of the warm water into the mouth and mix with the saliva as completely as possible. Transfer the liquid so obtained into another beaker and then filter through a small fluted filter-paper into a small conical flask or boiling-tube. Place io ml. of i% starch solution (prepared as described above) in a boiling-tube, add 2 ml. of i% sodium chloride solution and place the tube in a water-bath maintained at 38-40°. Place about 5 ml. of water in a series of test-tubes and to each add a few drops of i% iodine solution. Now add 4 ml. of the diluted saliva solution to the starch solution, mix well and note the time. At intervals of about 30 seconds
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This note was uploaded on 09/19/2011 for the course CHM 2211 taught by Professor Castalleano during the Fall '06 term at University of Florida.