Abstract: The objective of this study was to investigate the inhibitory effects of four spice extracts on the oxidation of porcine myofibrillar protein (MP) during exposure to a Fenton reaction system (FRS) for 0, 1, 3 or 5 h. The results indicated that the addition of clove extract (CE), rosmary extract (RE) or cinnamon extract (CME) significantly inhibited protein carbonyl formation (P < 0.05), but the effect of lcorice extract (LE) was not significant. Both CE and RE significantly inhibited the decrease of Ca-ATPase activity (P < 0.05); however, LE and CME had no inhibitory effect. Each of the four spice extracts strongly inhibited the increase of surface hydrophobicity. CE, RE and LE significantly inhibited the decrease of solubility (P < 0.05), while the effect of CME was not significant. The addition of each of the four spice extracts accelerated the decrease of protein sulfhydryl group content. In conclusion, CE and RE had better inhibitory effect on porcine MP oxidation.

Key words: myofibrillar protein, protein oxidation, spice extract, antioxidant properties