THE  AMERICAN 
JOURNAL  OF  PHARMACY 
rULYt  1905. 
A  COMPARATIVE  STUDY  OF  VARIOUS  FRUIT  AND 
VEGETABLE  COLORS.1 
By  Charges  H.  LaWai^i,,  Ph.M, 
A  comparative  study  of  various  coloring  materials  is  desirable  at 
the  present  time  on  account  of  the  frequency  with  which  questions 
arise  concerning  the  authenticity  of  given  samples  of  fruit  syrups 
and  fruit  juices,  and  in  consequence  of  legislative  attempts  which 
have  recently  been  made  to  legalize  the  use  of  certain  harmless 
colors  of  vegetable  origin  where  conditions  arise  in  which  the  origi- 
nal fruit  colors  are  not  permanent. 
There  is  no  intention  whatever  to  discuss  the  physiological  effect 
of  the  vegetable  colors  as  contrasted  with  the  so-called  coal-tar  or 
aniline  colors  (which  might  be  more  appropriately  referred  to  as 
the  synthetic  colors). 
There  is  no  doubt  that  the  synthetic  colors  as  made  at  the  pres- 
ent time  are  free  from  the  dangerous  metallic  impurities,  such  as 
arsenic,  which  were  formerly  associated  with  these  colors  on  account 
ot  the  then  existing  methods  of  manufacture ;  and  at  the  present 
time  the  feeling  against  the  coal-tar  colors  seems  to  be  based  upon 
theoretical  grounds  due  to  their  pronounced  tinctorial  affinity  for 
animal  tissues,  rather  than  upon  any  observations  of  the  ill  effects 
following  the  administration  of  such  colors  as  a  class. 
Many  specific  laws  have  been  passed  in  various  European  coun- 
tries regulating  the  use  of  coloring  matters  in  foodstuffs,  and  in 
some  cases  attempts  have  been  made  to  legalize  the  use  of  certain 
colors,  which  have  been  proved  to  be  harmless,  regardless  of  their 
origin. 
XA  thesis  presented  to  the  Philadelphia  College  of  Pharmacy  for  the  degree 
of  Master  in  Pharmacy,  Ph,M,,  in  course,  May,  1905. 
(301) 
