Am.  Jour.  Pnarm.  \ 
February,  19 19.  ■> 
Cacao  Shell. 
in 
Germany  were  poisoned  by  being  fed  on  cacao  shells  (2%  lb.  per 
meal).  It  was  suggested  that  this  was  due  to  the  theobromine  pres- 
ent in  the  shell.  We  feel  that  this  is  doubtful,  considering  that 
cacao  shells  have  so  long  been  used  in  compound  feeding  cakes  with- 
out complaint.  It  suggests,  however,  that  it  is  probably  unwise  to 
use  a  high  percentage  of  it  in  a  diet.5 
Early  in  191 5  the  transport  difficulties  were  so  great  that  manu- 
facturers of  cocoa  could  not  get  rid  of  their  shell  and  hence  some 
thought  was  given  to  ways  of  using  it.  It  has  been  used  as  fuel. 
Its  calorific  value  is  a  little  greater  than  that  of  wood  (varying  from 
7,400  to  8,600  B.Th.U.),  but  being  very  light  it  needs  careful  man- 
agement. It  is  most  effectively  used  on  a  gas  plant,  the  only  objec- 
tion being  that  the  tar  which  it  produces  has  a  nauseating  odor. 
The  charred  residue  can  be  used  as  a  manure.  The  shell  itself  has 
been  used  as  a  manure.6  In  experiments  at  Bournville  it  was  found 
to  decompose  in  the  ground  very  slowly,  and  Mr.  J.  Lodge  recom- 
mends that  the  decomposition  should  be  hastened  by  placing  the  shell 
in  a  heap,  soaking  well  with  water,  and  turning  several  times 
previous  to  use  on  the  land.  Used  in  this  way  it  gave  excellent 
results  both  as  a  manure  and  as  a  lightener  of  heavy  soils. 
The  fat  in  cacao  shell  can  be  extracted  by  solvents,  and  as  "  shell 
fat "  is  seen  on  the  market  from  time  to  time ;  this  is  presumably  a 
regular  practice  on  the  Continent.  This  solvent-extracted  fat  has 
an  unpleasant  taste  and  an  odor  like  tobacco,  which  renders  it  unfit 
for  edible  purposes.  With  theobromine  fetching  fifty  shillings  a 
pound  the  extraction  of  the  theobromine  from  shell  appears  a  feas- 
ible proposition.  We  know  of  no  firm  actually  doing  this,  although 
presumably  either  shell  or  germ  is  the  source  of  the  theobromine 
now  sold.  As  an  experiment  we  ourselves  extracted  some  sixty 
pounds,  which  we  had  no  difficulty  in  selling. 
Shell  can  be  made  to  give  an  extract  which  is  equal  to  some  of 
the  coffee  substitutes  at  present  sold,  and  many  other  applications 
have  been  suggested,  but  the  use  of  shell  which  is  the  most  interest- 
ing and  regrettable  is  in  cocoa  and  chocolate.  In  Belgium,  Switzer- 
land, Austria,  Germany,  and  America,  it  is  illegal  to  put  shell  in 
cocoa  or  chocolate,  the  shelled  bean  being  used.  In  Great  Britain 
until  this  year  the  amount  of  shell  that  might  be  present  in  cocoa 
and  chocolate  had  not  been  defined.    The  Food  Controller  has  now 
5  See  "  Cacao  Shells  as  Fodder,"  by  A.  W.  Knapp,  Tropical  Life,  1916. 
154. 
