Bologna type sausages were prepared from oxidatively stressed pork (UV-irradiation, 48 h, 5 °C) using a
traditional recipe (control) or the same recipe but added green tea extract (500 ppm total phenolic
compounds) or rosemary extract (400 ppm total phenolic compounds). Green tea and rosemary extracts
protected against formation of TBARS and protein carbonyls. On the contrary, increased thiol loss and a
distinct loss of myosin heavy chain and actin due to polymerization by reducible bonds as determined by
SDS-page were found by addition of green tea extract. The enhanced protein polymerization was ascribed
to the reaction between quinone compounds from the plant extracts and protein thiol groups to yield
phenol-mediated protein polymerization. Analysis by ESR spectroscopy revealed increased radical intensities
in sausages added plant extracts, which was ascribed to originate from protein-bound phenoxyl radicals,
which may protect against other oxidatively induced protein modifications