Effects of Co-fermentation with Lactic Acid Bacteria and Staphylococcus with Antioxidant Activity on the Quality of Cantonese Sausages

To explore the effects of starter cultures with antioxidant activity on the quality of Cantonese sausage, this study used pork frozen at -20 ℃ for 0, 3, 6 and 9 months to make Cantonese sausages (denoted respectively as 0E, 3E, 6E and 9E) employing a mixed-strain starter culture of Lactiplantibacillus plantarum L52, Pediococcus pentosaceus L256, Staphylococcus xylosus S56 and S. xylosus S236 (L52: L256: S56: S236 = 5:10:2:3, V/V), all having antioxidant potential. Uninoculated sausages were also produced as controls and designated as 0C, 3C, 6C and 9C, respectively. The changes of microbial counts, sensory quality and physicochemical indexes were analyzed during sausage processing. Results showed that prolonged freezing time inhibited the growth of some microorganisms in pork. At the middle stage of fermentation, the numbers of lactic acid bacteria and Staphylococcus were significantly higher in the experimental group than in the control group (P < 0.05). Prolonged freezing time of pork meat reduced the sensory quality of sausages, and the sensory quality of the experimental group was better than that of the control group. The overall sensory score of 9E (71.85 points) was significantly higher than that of 9C (59.60 points). The pH and water activity (a_w) of the experimental group were lower than those of the control group. Prolonged freezing time of pork meat led to a higher degree of oxidation of sausages. After drying, the thiobarbituric acid reactive substances (TBARS) value, carbonyl group value (CGV) and protein carbonyl content of 6E were 29.66%, 26.32% and 23.72% lower than those of 6C (P < 0.05), and the protein sulfhydryl content was 40.36% higher than that of 6C (P < 0.05). Compared with 6C, the intensity of the bands in the ranges of 18-27 and 27-55 kDa, corresponding respectively to sarcoplasmic and myofibrillar proteins, were significantly enhanced in 6E. The total content of biogenic amines was 25.15% lower in 3E than in 3C. The total content of ethyl esters was significantly higher in 9E (8.81 μg/kg) than in 9C (2.91 μg/kg) (P < 0.05). The results showed that the four-strain cocktail of lactic acid bacteria and Staphylococcus could improve the antioxidant activity, eating quality and safety of Cantonese sausages.