Ah.  Jetm.  Pharu«V 
D©e.  1, 1871.  j 
Adulteration  of  Food. 
561 
are  content  to  accept  such  a  palpable  imposture  as  "genuine  green." 
It  is  a  matter  of  opinion  whether  cocoa  as  ordinarily  sold  is  to  be 
considered  an  adulterated  or  a  manufactured  article.  It  is  seldom 
sold  pure  and  alone ;  being  usually  mixed  with  starch  and  sugar — 
the  term  "pure  cocoa"  is,  therefore,  in  most  cases,  intended  to  mis- 
lead. Some  kinds  have  lard  or  suet  admixed,  and  to  others  red  ochre 
is  added  to  bring  up  the  color,  rendered  pale  by  an  excessive  quantity 
of  starch.  The  relative  quantities  of  these  component  parts  in  any 
sample  of  cocoa  may  be  readily  ascertained  by  the  microscope ;  that 
of  starch  may  be  roughly  seen  by  shaking  up  some  of  the  cocoa  with 
water  in  a  test-tube  or  tall  bottle,  breaking  up  the  lumps,  and  then 
allowing  all  to  settle ;  when  the  starch  will  sink  to  the  bottom  and 
form  a  white  layer  beneath  the  cocoa.  On  warming  the  water,  the 
fat  will  of  course  float  on  the  top,  and  the  sugar  will  be  dissolved. 
The  sugar  crystals  and  fat  are  also  shown  by  re-drying  the  solution 
on  a  glass  slide. 
Sugar  is  mixed  with  inferior  kinds  of  the  same  article,  but  not  (as 
popularly  believed)  with  sand ;  the  chief  impurities  in  raw  sugar  are 
cane  fibre,  accidental  dirt,  and  the  sugar  mite  or  acarus.  The  latter 
exists  in  most  raw  sugars  (out  of  72  samples  69  contained  mites) ; 
but  more  abundantly  in  the  moderately  brown  kinds  than  in  the 
darker.  The  insect  is  barely  visible  to  the  naked  eye.  To  obtain 
specimens,  the  sample  should  be  dissolved  in  tepid  water  and  well 
stirred,  then  allowed  to  stand  a  few  minutes,  and  the  acari  will  be 
found  as  minute  particles  floating  on  the  top.  The  process  of  refining 
entirely  removes  these  and  the  other  impurities  named. 
Mustard  is  invariably  adulterated  with  flour,  which  forms  one-half 
or  three-fourths  of  the  article  as  usually  sold.  It  may  be  readily  de- 
tected by  the  microscope,  mustard  itself  containing  no  starch  what- 
ever. Turmeric  is  often  added  to  bring  up  the  color  after  this  whole- 
sale admixture,  and  cayenne  to  give  it  strength. 
Pepper  may  now  be  obtained  pure  of  respectable  dealers ;  but  as 
regards  the  cheaper  kinds,  and  in  poor  neighborhoods,  it  is  largely 
adulterated  with  meal  or  starch,  gypsum,  and  dirt  of  any  kind,  to 
give  bulk  and  weight.  The  starchy  substance  may  be  detected  by 
the  microscope,  the  earthy  ones  will  be  left  as  ash  after  burning,  and 
their  character  may  be  ascertained  by  the  polariscope.  The  particles 
of  pepper  itself  are  easily  recognised  by  the  characteristic  stellate 
36 
