Am.  Jour.  Pharm. 
May,  1909. 
Capsicum  in  Ginger, 
219 
alkaline  solution  of  the  residue  to  the  test-tube,  insert  a  perforated 
cork  bearing  a  glass  tube  about  1  m.  long,  to  serve  as  a  reflux  con- 
denser, stand  the  test-tube  in  a  beaker  of  water  upon  a  water  bath 
(supporting  the  tube  by  a  suitable  apparatus  stand),  and  maintain 
the  temperature  at  a  degree  sufficient  to  cause  a  gentle  ebullition 
of  the  alcoholic  solution  for  thirty  minutes.  Remove  the  stopper 
and  glass  tube  and  continue  the  heat  until  the  alcohol  is  evaporated 
and  the  residue  in  the  test-tube  is  nearly  dry.  Add  water  to  fill  the 
test-tube  half  full,  agitate  to  dissolve  the  saponified  residue,  add  an 
amount  of  ether  equivalent  to  one-half  the  volume  of  the  aqueous 
solution  and  again  agitate  thoroughly.  After  the  ethereal  solution 
has  separated,  draw  it  off  by  means  of  a  pipette,  transfer  to  a  clean 
dry  watch  glass  and  allow  it  to  evaporate  spontaneously.  After  the 
evaporation  of  the  ether  taste  the  residue  upon  the  watch  glass. 
Capsicum  is  indicated  by  a  sharp  pungency  as  soon  as  the  tip  of  the 
tongue  touches  the  residue.  When  large  quantities  of  ginger  are 
used  a  slight  camphoraceous  taste  is  observed,  but  there  is  never  any 
pungency  unless  capsicum  is  present. 
This  method  has  been  tried  under  varying  conditions  upon 
several  hundred  specimens  of  known  origin  and  has  never  failed 
to  indicate  capsicum  when  present,  nor  has  there  been  any  difficulty 
in  distinguishing  the  residue  left  from  pure  ginger  preparations. 
Experiments  upon  quantitative  mixtures  have  shown  that  it  is  easily 
possible  to  detect  one  part  of  capsicum  in  10,000  parts  of  water, 
which  is  equal  to  one  pound  of  capsicum  in  600  gallons  of  ginger 
ale. 
The  method  is  applicable  to  any  other  preparation  of  ginger  by 
driving  off  the  alcohol,  if  present,  diluting  with  water,  acidulating 
and  shaking  out,  as  in  the  foregoing  method. 
