Am'ju°yjfo8.arm"}    Examination  of  Commercial  Ginger.  315 
washing  produces  an  effect  similar  to  that  found  in  exhausted  ginger. 
Furthermore,  it  should  be  stated  that  on  the  keeping  of  ginger  the 
contents  of  the  secretion  cells  are  oxidized  and  changed  in  color,  as 
well  as  rendered  insoluble  in  such  solvents  as  alcohol,  ether,  acetone, 
glacial  acetic  acid,  potassium  hydrate  solution,  and  chloral  hydrate ; 
whereas,  in  the  recently  dried  material,  in  the  fresh  rhizome  and  in 
preserved  ginger  the  contents  are  of  a  distinct  light  yellow  or  yellow 
color,  the  oil  is  in  the  form  of  globules,  and  the  contents  are  easily 
removed  by  means  of  any  of  the  foregoing  solvents.  It  would  thus 
appear  that  the  fresher  the  ginger  the  better  it  is  in  quality. 
While  in  the  past  a  number  of  substances  have  been  used  in  the 
adulteration  of  ginger,  at  the  present  time  apparently  exhausted 
ginger  is  chiefly  used,  its  deficiency  in  pungency  being  made  up  by 
the  addition  of  a  small  amount  of  capsicum  or  Cayenne  pepper.  In 
the  examination  of  ground  ginger  for  the  detection  of  exhausted 
ginger  or  other  adulterants,  the  following  points  should  be  borne  in 
mind  : 
1.  Physical  appearance.  In  powdered  ginger  the  material  is 
more  or  less  uniform  and  granular,  whereas  in  the  exhausted  powder 
the  fibrous  character  of  the  material  is  especially  manifest.  The 
color  of  exhausted  ginger  is  considerably  lighter  ;  the  odor  is  strik- 
ingly less  aromatic  and  the  taste  is  less  pungent,  unless  capsicum 
has  been  added,  in  which  case  the  characteristic  pungency  of  this 
condiment  is  evident. 
2.  When  ether-extracted  ginger  is  dropped  on  the  surface  of 
water,  the  particles  are  not  distributed  rapidly  over  the  surface,  and 
show  a  tendency  to  form  a  scum  on  the  water,  as  is  the  case  with 
wheat  flour. 
3.  On  adding  sulphuric  acid  to  exhausted  ginger,  a  greenish- 
brown  color  at  first  develops,  which  becomes  darker,  the  reagent 
itself  not  being  colored. 
4.  With  phloroglucin  the  stone  cells  of  capsicum  {Fig.  5,  y)  turn 
to  a  cherry-red,  as  also  the  lignified  cells  of  soap  bark.  The 
cells  of  the  sarcocarp  of  capsicum  containing  red  chromoplasts  are 
readily  detected  when  the  material  is  mounted  in  chloral  or  fixed 
oil. 
5.  When  ginger  has  been  exhausted  with  water  or  dilute  alcohol, 
a  comparatively  larger  number  of  the  starch  grains  have  bursted  or 
have  a  swollen  appearance  at  one  end,  and  in  among  the  grains  are 
