AOAC Official Method 939.04 Chlorine in Fat of Flour
First Action 1939
Final Action 1965
A. Qualitative Test
Extract 30 g test portion with 50mLpetroleum ether and let solvent evaporate. (Small amount of oil remains.) Heat piece of Cu wire in colorless gas flame until it is black and no longer colors flame green. Dip hot end of wire into oil and again bring into flame. If Cl2 or Br2 has been used as bleaching agent, green or blue coloration is produced.
