272  Commercial  Glucose  and  its  Uses.  {^'j^'m^' 
has  been  found  to  be  the  most  desirable  for  imparting  to  the  prod- 
uct the  properties  most  suited  for  a  syrup  which  can  be  refined 
readily,  and  at  the  same  time  contain  enough  colloidal  material  to 
prevent  its  crystallizing  at  any  concentration.  This  colloidal  matter 
also  renders  the  syrup  capable  of  dissolving  considerable  amounts 
of  cane-sugar  without  crystallization.  Such  a  product  is  peculiarly 
valuable  in  the  preparation  of  syrups,  candies,  preserves,  and  jellies, 
quite  apart  from  its  use  as  a  sweet.  It  also  contains  nearly  the 
maximum  amount  of  malt  sugar  that  can  be  produced  by  such  a 
process. 
The  rest  of  the  dissolved  substance  of  commercial  glucose  con- 
sists of  0.3  to  0.5  per  cent,  of  mineral  matter,  mostly  composed  of 
sodium  chloride  from  the  neutralization  with  soda  of  the  hydro- 
chloric acid  used  in  the  manufacture,  sulphites  which  are  added  at 
various  stages,  phosphates  and  other  salts  from  the  natural  mineral 
matters  present  in  minute  quantities  in  the  starch  or  coming  in 
part  from  the  bone-black  used  in  the  refining  process.  There  is  also 
about  0.08  per  cent,  of  nitrogen,  corresponding  to  five  or  six  times 
its  weight  of  organic  substances  from  the  gluten  left  in  the  starch. 
Much  of  this  nitrogenous  matter  is  not  gluten,  but  simpler  organic 
compounds  resulting  from  the  action  of  the  acid  (used  to  convert 
the  starch)  /on  the  gluten.  These  nitrogenous  matters  have  much  to 
do  with  the  quality  of  the  glucose,  and  it  is  on  this  account  that 
they  are  of  peculiar  importance,  although  present  in  minute  amounts. 
The  impurities  from  the  gluten  which  are  less  acted  upon  by  the 
acid,  the  "  albumoses,"  give  trouble  to  the  candy  manufacturer  by 
causing  foaming  in  his  kettles,  while  this  property  is  the  joy  of  the 
brewer.  Those  gluten  substances  which  are  changed  further  by  the 
acid,  the  "  amino  bodies,"  tend  to  make  the  glucose  darker  and  also 
impart  a  flavor  which,  though  barely  perceptible,  is  disagreeable- 
bitter  or  fishy.  Manufacturers  used  to  correct  the  objectionable 
effects  of  these  impurities  by  the  addition  of  sulphites  to  the  glucose, 
but  this  was  but  a  temporary  expedient  and  undesirable  in  a  food 
product.  Glucose '  has  been  much  improved  in  recent  years  by 
practically  eliminating  the  effect  of  these  impurities  by  more  effi- 
cient purification  of  the  starch  used  in  its  manufacture. 
The  glucose  process  does  not  end  with  the  acid  treatment  of  the 
starch  and  the  neutralizing,  as  at  this  stage  the  dilute  syrup  is  far 
from  pure,  containing  oily  matters  from  the  corn,  some  undecom- 
posed  gluten  and  other  impurities,  mostly  in  suspension.  This 
