A comparative evaluation of various methods used to determine rancidity inmeat products

The study has compared the methods being most suitable to measure the ranci dity of processed meats. In order to generate samples in different slates o f oxidation, portions of cured (Bologna), fresh, and fermented (Genoa) saus ages were first stored for various periods of time in an oxygen-enriched at mosphere. The degree of rancidity of the oxidized samples was subsequently evaluated using an aqueous-acid extraction method (adapted from WITTE et al ., 1970), an aqueous-acid extraction TBA-C,, method (adapted from RAHARJO e t al., 1992), or hexanal content determination by headspace GLC. The result s were compared to those obtained with the classical distillation method of TARLAGDIS et al. (1960). Even though the TBX values calculated from the cl assical and alternative methods were generally significantly (p < 0.05) dif ferent, they were strongly correlated (R-2 = 0.8042 - 0.9999) in the range of values measured (0.19 - 15.32 mg malonaldehyde.kg(-1)). The correlation was the highest in fresh sausage (R-2 > 0.9925) and for the aqueous-acid ex traction TBA-C-18 method (R-2 = 0.9237-0.9999). The hexanal contents were a lso well correlated (R-2 = 0.9366 - 0.9852) with TARLAGDIS's TEA values. If a strong correlation with the TARLAGDIS method is wanted, the aqueous-acid extraction TBA-C-18 and headspace GLC methods are therefore the best choic es; the latter being more rapid but also more expensive and technically cha llenging. Ii a lower correlation is acceptable, the aqueous-acid extraction method is a good choice, with respect to rapidity and cost.