Study On Application Of Celery Powder High In Nitrate In Fermented Meat Product

In this study, celery powder high in nitrates combined with a nitrate reducing bacterial starter culture, Staphylococcus xylosus (S. xylosus) and Staphylococcus carnosus (S. carnosus), were used to substitute the inorganic sodium nitrite and to provide similar quality and sensory to nitrite-added cured meats. Moreover, the potential application of the celery powder high in nitrates in the product process was discussed.By doing some fermentation tests, the results shown that both S. xylosus and S. carnosus produced lipase, proteinase, catalase-positive and nitratereduction activity. The growth ability of S. xylosus and S. carnosus were also tested at different NaCl, nitrite and nitrate concentrations. The results showed that they were suitable to make starter cultures. During the process of fermented sausages, the two strains still displayed nitrate reduction activity and could reduce nitrate into nitrite. Through the determination of growth curves and nitrate reductase curves of S. xylosus and S. carnosus, the strains cultivated 16 h were choosed for the tests later.And then, the application methods of the celery powder high in nitrates, including the technological parameters were studied. The research has studied that celery powder , S. xylosus and S. carnosus are applied to fermented sausages as natural ingredients. Considering products'objective color a* value (redness) and residual nitrite as the criterions,. Afterdoing single-factor experiment to get better process conditions. Orthorgonal experiment was carried on to confirm best technology parameters of four factors as: temperature of fermentation is 30℃, time of fermentation is 30 h, the amount of strains inoculation is 107 cfu/g, S. xylosus : S. carnosus =1:2.Last, the qualities such as the sensory evaluation, texture, residual sodium nitrite, the growth of Lactic acid bacteria and Micrococcaceae, the POV and TBARS values of fermented sausage with celery powder were discussed and compared with the traditional fermented sausage(added 150 mg/kg nitrite) during the storage. The results showed that: the residual nitrite level of the natural fermented sausage was lower than the traditional fermented sausage throughout the storage. The former was kept the level of 4.61 mg/kg, the latter was 8.08 mg/kg; Both the samples Lactic acid bacteria dominated the microflora from the beginning of storage. Growth of Micrococcaceae in control was inhibited, appearing to be significantly affected by acidification or other floras of the sausage;The POV values of the natural fermented sausage were lower than the traditional fermented sausage. Though the TBARS values of the former were higher than the latter, they were always below the level of 1.0 mg/kg. This demonstrated that there was no obvious oxidation phenomenon in the control.