Microdetermination of thiobarbituric acid values in marine lipids by a direct spectrophotometric method with a monophasic reaction system

Abstract A rapid direct spectrophotometric method for determining the thiobarbituric acid (TBA) value in lipids is reported. The variation in TBA value given by different reaction conditions has been investigated systematically and a monophasic TBA reaction system with incorporation of sulfite reagents has been selected for the recommended method, which can be used to determine the TBA value at levels as low as 2 nmol of malonaldehyde equivalent in 20 mg of lipids with a standard deviation of less than 8%. The procedure has been applied to some marine lipids, including highly colored or oxidized samples.