Rapid colorimetric determination of free fatty acids
- Cite this article as:
- Lowry, R.R. & Tinsley, I.J. J Am Oil Chem Soc (1976) 53: 470. doi:10.1007/BF02636814
In 1964, a method was described for the determination of free fatty acids (FFAs) in vegetable oil. This paper describes an expansion of that work, improving the sensitivity and reproducibility of the method, as well as examination of solubilities of the copper soaps as a function of chain length and unsaturation. Involvement of the micellar structure was reviewed. Finally, a procedure is described that permits very rapid determination of FFA at the 2.0–14.0 µmol (0.5–4.0 mg oleic acid) level, and the results with several oils are given. Particular attention was given to evaluation of solvent systems which would extract the copper complexes.