Am.  Jonr.  Pharm. ) 
April,  1885.  J 
Hop  Extract, 
167 
menstruum.  The  extract  in  the  boiler  on  cooling  to  a  certain  tempera- 
ture, is  drawn  oif  and  subsequently  canned,  in  which  condition  it  will 
keep  for  an  indefinite  period,  a  great  advantage  over  the  hop  itself, 
which  at  the  end  of  two  years  is  nearly  useless.  One  pound  of  this 
extract  represents  about  twelve  pounds  of  choice  hops.  About  two 
thousand  pounds  of  hops  can  be  exhausted  in  these  works  during 
twenty-four  hours.  Hie  only  use  made  of  this  extract  at  present  is  in 
the  manufacture  of  beer,  for  which  purpose  it  is  at  present  being  used 
to  a  large  extent  in  Philadelphia  and  New  York,  fully  supplying  the 
place  of  the  ordinary  hop.  ; 
On  investigation  quite  a  difference  was  observed  between  this  extract 
and  the  one  made  by  myself,  the  former  being  of  an  intense  black  color, 
appearing  to  be  more  oily,  and  containing  practically  no  tannin  or  a 
mere  trace,  while  in  the  extract  made  by  myself  between  7  per  cent, 
and  8  per  cent  of  tannin  was  indicated  by  using  a  solution  of  acetate  of 
lead. 
The  amount  of  glucose  was  ascertained  ^by  Fehling's  solution, 
and  found  to  be  in  my  extract  12  per  cent.,  but  in  the  patent  extract, 
a  little  over  16  per  cent.  During  this  investigation  the  writer  obtained 
results  more  easily  from  the  patent  extract  than  from  the  extract  made 
by  himself. 
On  exposing  the  extract  made  by  me  to  a  temperature  of  100°C. 
until  it  ceased  to  lose  weight,  13  per  cent,  of  volatile  matter  was 
expelled,  and  at  110°  C.  it  lost  an  additional  9  per  cent.,  becoming 
quite  dry,  darker  in  color,  losing  its  aroma  and  breaking  with  little 
difficulty  into  small  pieces.  The  patent  extract  exposed  to  100°  C. 
lost  only  '05  per  cent,  in  weight  and  at  110°  C,  this  loss  was  increased 
by  only  an  additional  '03  per  cent.  This  high  heat  seemed  to  have  but 
very  little  effect  on  it,  either  in  changing  its  color,  or  destroying  its 
odor. 
The  effect  of  different  solvents  on  the  two  extracts  showed  a  very 
marked  difference.  Water  dissolved  only  a  very  small  portion  of  the 
extract  made  by  me,  leaving  a  brown  residue,  which  was  apparently 
mostly  resin  and  oil.  Alcohol  had  only  a  slight  effect,  but  dilute 
alcohol  took  up  more.  All  of  the  ordinary  solvents  were  tried,  and 
none  of  them  completely  dissolved  this  extract. 
The  patent  extract  was  found  to  be  practically  insoluble  in  water, 
and  also  in  cold  alcohol,  but  hot  alcohol  held  it  in  solution  as  did  also 
benzin.    It  is  more  soluble  in  ether  and  completely  soluble  in  chloro- 
