Five milliliters of extracting solution (5 mL 500 mM propyl gallate, 5 mL 500 mM EDTA (Acros, New Jersey, USA) and 60 mM trichloroacetic acid (Panreac, Espana) in 500 mL distillated water) were added to 1 g of meat sample and mixed (3 × 15 s in an Ultraturax T-25 basic, Janke & Kunkel IKA-Labortechnik, Staufen, Germany).