Key points are not available for this paper at this time.
Abstract The possibilities of the direct determination of the thiobarbituric acid (TBA) value in trichloracetic acid (TCA) extracts instead of distillates were evaluated. Tests carried out on herring (Clupea harengus L.), redfish (Sebastes marinus L.), cod (Gadus morhua L.), plaice (Pleuronectes platessa L.) and spurdog (Squalus acanthias L.) of varying degree of oxidation gave 95.3% recovery in the teleost species but only 75.2% in the elasmobranch spurdog, due to the urea present. With the distillation technique, recoveries were lower and averaged 66.1% for teleosts and 43.0% for spurdog. Addition of 0.1% of both propyl gallate and EDTA to the TCA solution lowered TBA values by 25 to 59%. When fish samples were submitted to a 4 hours′ forced oxidation period, TBA values increased to a greater extent with the direct extraction procedure than with the distillation method.
W. Vyncke (Thu,) studied this question.