| The acid value (AV), peroxide value (POV), thiobarbituric acid value (TBA) and sensory characteristics of seven kinds of fifteen varieties of meat products from supermarkets were investigated, in order to evaluate the oxidative safety of meat products. With 1/3-1/2 of the shelf life, nine samples had qualified sensory characteristics, but their AV were approaching to or over the national AV standard, with the AV safety time of only 1/5～1/3 of the shelf life. However, POV obtained from these samples were significantly lower than the national standard, resulting in the much longer oxidative safety shelf life. Regarding to the TBA value, the TBA oxidation safety time was closer to their shelf life, evidenced by the sensory evaluation. The results showed that AV was unsuitable as meat food safety index, due to its not agreement with their actual sensory quality. For the similar reasons, POV was also unfavorable as meat safety index. TBA value, however, due to its safety significance, and reflection of the actual oxidation performance, can be used as safety oxidative indicators for meat products.Propolis and other natural antioxidants were used for preparation of Cantonese style sausage to compare their antioxidant effect. The group with propolis (0.03%, w/w) had lover AV, POV, TBA values compared with the blank control. The group added with lipase (0.03%, w/w) had the oxidative safety index much higher than the blank control. The oxidative safety index showed ascendant trend in the group added with both propolis (0.06%, w/w) added and lipase (0.03%, w/w), but the propolis added group was relatively lower than the lipase added group. The results showed that propolis had antioxidative effect on Cantonese style sausage, and can effectively inhibit fat hydrolysis.The antioxidant effect of propolis was not significant in early-storage of meat products, but was more obvious during late storage time. AV, POV and TBA, at the first 25 d of storage time, were 7.67 mg KOH/g (fat),0.28 g/100 g (fat),2.34 mg/kg (sample) for the blank groups,4.48 mg KOH/g,0.18 g/100 g,1.86 mg/kg for the propolis added groups, and 4.35 mg KOH/g,0.11 g/100 g,1.46 mg/kg for the treatment groups with propolis and Vc complex. The results showed that Cantonese style sausage under normal storage temperature for 25 d without treatment with any antioxidant had AV above the national standard. However, propolis combined with Vc can improve their oxidative safety, and extend their shelf life.Propolis at level of 0.04% (w/w) inhibited effectively oxidation of the Cantonese style sausage with minimal impact on its sensory quality. The inhibition effect increased with the added level of propolis. In the first 25 d, AV in the blank group was near 7.76 mg KOH/g, while it in the propolis groups (0.03%,0.04%,0.06%,0.08% w/w) was 5.69,4.24,3.38 and 3.11 mg KOH/g, respectively. This may be due to the antioxidant activity of propolis and its film formation characteristic.In conclusion, the propolis can effectively improve the oxidative safety of Cantonese style sausage and can prevent oxidation and prolong shelf life of meat products.
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