496 
Analysis  of  Lemon  Syr  tips. 
f  Am.  Jour.  Pharm. 
I     October,  1898. 
syrup  polarized  to  the  right,  and  contained  no  saccharose,  the  results 
were  reckoned  as  dextrose.  The  method  used  for  the  detection  of 
saccharose  depends  upon  its  inversion  by  hydrochloric  acid. 
Twenty-five  c.c.  of  the  5  per  cent,  solution  were  allowed  to  stand 
over  night  with  2-5  c.c.  of  hydrochloric  acid  of  I* I  specific  gravity, 
the  solution  neutralized  with  soda,  made  up  to  ico  c.c,  and  titrated. 
The  polarimeter,  however,  showed  that  no  reducing  sugar  had  been 
formed,  and  therefore  no  saccharose  was  present  in  the  sample. 
Though  the  5  per  cent,  syrup  solution  showed  on  the  day  after  its 
preparation,  a  rotation  of  -J-  21 '9  Ventzke  (length  of  tube  ==  2  deci- 
metres), only  1*5  per  cent,  of  dextrose  anhydride,  corresponding  to 
a  rotation  of  -f-  4-9  Ventzke,  had  been  found.  This  led  the  author 
to  suspect  the  presence  of  very  impure  starch-sugar  containing 
amylin,  which  was  confirmed  in  the  following  way  :  Ten  grammes 
of  the  sample  were  dissolved  in  water,  neutralized  while  hot  with 
precipitated  calcium  carbonate,  filtered  hot,  the  precipitated  calcium 
citrate  with  the  excess  of  carbonate  washed  with  boiling  water,  the 
filtrate  cooled  and  fermented  with  must.  It  was  then  neutralized 
while  hot,  evaporated,  treated  first  with  lead  acetate  and  then  with 
sodium  sulphate,  made  up  to  100  c.c.  and  filtered.  The  liquid 
showed  after  four  hours  as  well  as  after  twenty-four  hours  a  rotation 
of  4-  21  Ventzke  =  -f-  y°  \  Jf  (2  decimetre  tube),  whilst  its  power  of 
reducing  was  equal  to  o  65  gramme  dextrose  anhydride  in  100  c.c., 
corresponding  to  -\-  2  Ventzke. 
The  glycerin  was  tested  for  by  the  German  official  method  for  the 
analysis  of  dry  wines,  but  none  was  found. 
In  analyses  of  lemon-juice  the  following  results  were  obtained: 
lemon  SYRUP. 
100  Grammes  contained 
Citric  acid  
Tartaric  acid  
Reducing-sugar  reckoned  as  dextrose  
Saccharose   
Amylin  
Total  extract  
Extract  minus  citric  and  tartartic  acids  and  reducing-sugar 
Mineral  matter  (ash)  
Polarization,  Ventzke  (length  =  2  decimetre  tube)  
I. 
II. 
III. 
675 
14-40 
5*42 
10-58 
Nil. 
10-70 
30-10 
38-42 
Nil. 
Nil. 
Present. 
Present. 
81-92 
80-56 
37*42 
26-02 
0-32 
0-72 
+  21-9 
+  19'0 
