AOAC Official Method 938.09 Fatty Acids (Volatile) in Seafood
Column Chromatographic Method
First Action 1938
Final Action 1960
A. Apparatus
(a) Steam distillation assembly.—See Figure 938.09. Assembly consists of boiler flask (3 L) giving steam at constant rate so as to produce constant rate of distillation, distillation flask, condenser, and 200 mL volumetric flasks as receivers. Standard distillation flask with side arm (ca 9mmod) attached near center of neck, and with steam inlet tube (ca 10 mm od), is satisfactory. Heating coil of steam generator is made by winding 5 ft. (1.5 m) 28 gage Chromel wire (or equivalent) around hollow pipe ca 0.25 in. (6 mm)) diameter and heating red hot to detemper wire. Leads into boiler flask are brass, Cu, or other nonferrous metal ca 3/32in. (2mm)diameter. Insulate and shield electric leads and contacts to avoid possible shorting and electric shocks.
Any similar distillation assembly may be used if it is of capacity to handle volumes specified in method and gives 57 ±2%recovery of acetic acid on distillation.
