.Am.  Jour.  Pharm.  "1 
April,  1887.  J 
Artificially  Colored  Red  Wine. 
201 
residue,  if  it  contains  the  substances  named,  behaves  in  the  manner 
described  below  : — 
With  concentrated 
H2S04. 
HC1. 
NaHO. 
violet-red 
blue 
red 
blue 
carmine 
carmine 
carmine 
carmine 
Ponceau,  RRR.... 
dark-red 
crimson 
crimson 
brown 
violet-purple 
yellow 
yellow- 
red 
brown 
Vinicoline  Bor- 
delaise  
cherry-red 
brown 
red 
brown 
whilst  the  wine  after  extraction  is  cherry-red  with  ordinary  magenta, 
violet-red  with  acid-magenta,  dark-cherry  with  Bordeaux,  yellow-red 
with  ponceau.  Wine  colored  with  magenta  produces  a  violet  froth. 
The  detection  of  vegetable  coloring  matters  in  presence  of  the  natural 
oolor  of  wine  or  otherwise  is  a  matter  of  great  difficulty,  and  most  of 
the  known  methods  are  ineffectual ;  it  is,  however,  effected  by  the 
author  with  comparative  facility  in  the  following  manner: — 10  to  15 
oc.  of  wine  is  shaken  with  5  cc.  of  a  saturated  solution  of  tartar 
emetic,  and  then  examined  by  reflected  and  transmitted  light  either  at 
once  or,  if  no  immediate  change  has  taken  place,  after  some  time. 
This  treatment  produces  Avith  genuine  red  wine  always  a  cherry-red 
color,  and  with  other  substances  as  follows : — Red-poppy  (Papaver 
Rhazas),  dark  cherry-red;  cherry,  violet;  commercial  elder  coloring 
matter,  red- violet ;  bilberry  ( Vaccinium  Myrtillus),  blue- violet ;  privet- 
berry,  pure  violet.  White  wines  artificially  colored,  and  red  wines 
mixed  with  artificial  colors  have  been  successfully  examined  in  this 
manner ;  in  the  latter  case  the  wine  some  time  after  treatment  is  com- 
pared with  a  genuine  red  wine  to  distinguish  more  readily  the  change 
of  color.  Old  solutions  of  privet  do  not  give  the  color  change.  Sodium 
hydrogen  carbonate  produces  with  pure  elderberry,  grey -violet;  and 
with  bilberry,  brown-green.  Tartar  emetic  appears  to  form  an 
antimony  lake  with  the  coloring  matters.  With  practice,  all  the 
above-mentioned  colors  can  be  detected  in  30 — 50  cc.  of  wine.  In 
the  subsequent  communication  the  author  acknowledges  the  priority  of 
Ambuhl  and  Eisner's  recommendation  of  the  use  of  tartar  emetic  for 
the  purpose  in  question.  They,  however,  recommend  hot  solutions ; 
the  author  finds  cold  better.  Fermented  bilberries  give  the  violet 
color  even  better  than  unfermented  berries,  especially  when  fresh, 
inasmuch  as  oxidation  interferes  with  the  delicacy  after  a  time.  The 
distinctness  of  this  color  is  increased  by  diluting  the  wine. — Jour, 
Chem.  Soc,  Jan.,  1887,  p.  91  ;  Chem.  Ztg.  x.  968,  998. 
