Separation Screening Of Fermented Strain Fron Traditional Fermented Meat Products And Application In Beef Fermented Sausages

Fermented meat products are considered high-grade meat products.As a typical fermented meat product,fermented sausage is deeply loved by people.The production technology of fermented sausage in developed countries has been relatively mature,and there are relatively mature starters.Fermented sausages in our country are still dominated by traditional hand-crafted workshops,with few varieties,immature industrial production,no definite strains,and there are a series of problems.With the improvement of the consumption level in our country,people have higher and higher requirements for the quality and safety of fermented sausages.The development of fermented beef products in China should first select fermentation strains with excellent performance and promote the development of starter,so as to improve the fermentation characteristics of the product and make it consistent with the consumption and taste needs of the Chinese people.In this study,Yunnan bacon,ham and dry-cured beef were used as raw materials,and the selection criteria of meat product starters were used as the basis for selecting lactic acid bacteria strains with better fermentation performance and determining the fermentation characteristics of the strains.By studying the effect of single fermentation of lactic acid bacteria on the quality of beef sausages,lactic acid bacteria strains with better fermentation effects were obtained;lactic acid bacteria strains and the commonly used staphylococci in fermented meat products: The optimal ratio was determined,so as to study the effect of the combined effect of the compound strains on the sausage fermentation process under the optimal ratio.The specific research results are as follows:(1)Yunnan ham,bacon,and dry-cured beef were used as raw materials,the lactic acid bacteria were separated and screened,and 60 strains with obvious calcium-dissolving circle and typical lactic acid bacteria colony characteristics,gram-positive and catalase-negative,were obtained.Taking the meat fermentation characteristics of no H2O2,no gas,no H2 S,arginine,no ammonia,etc.from fermented glucose as indicators,the 60 strains of lactic acid bacteria isolated above were further screened,and the acid production characteristics,salt tolerance and salt tolerance of the strains were determined at the same time.Nitrite-tolerant,select a lactic acid bacteria strain that meets the basic requirements of meat starter and has the best acid-producing,salt-tolerant and nitrite-tolerant properties from Yunnan ham,bacon and dry-cured beef.They were identified as P.pentosaceus,L.sakei and W.cibaria.After further fermentation performance determination,the temperature adaptability and p H tolerance of P.pentosaceus,L.sakei and W.cibaria meet the basic conditions of lactic acid bacteria for fermented meat products,and can be further applied in fermented meat products.(2)The effects of fermentation of different single lactic acid bacteria on the quality changes of fermented beef sausages during the fermentation process were compared with KB(natural fermentation)were studied.The effects of adding L.sakei and P.pentosaceus fermentation on fermented beef sausages were significantly higher than the W.cibraia.L.sakei and P.pentosaceus can accelerate the decline of p H,Aw and water holding capacity in fermented sausages,speed up the fermentation speed,effectively slow down the production speed of TVB-N,and significantly improve the texture of fermented sausages;in addition,significantly reduce the number of Enterobacter in the sausage(but still detected),which improves the microbiological safety of the product.However,the fermentation of single lactic acid bacteria has no significant effect on the color of the product,and the flavor analysis of the electronic nose shows that there is a certain difference between the flavor of single lactic acid bacteria fermentation and natural fermentation.Considering the fermentation effect comprehensively,the fermentation effect of single strains of L.sakei and P.pentosaceus is better than that of W.cibraia.(3)The effect of the combination of L.sakei and P.pentosaceus with S.carnotus on the quality of fermented beef sausage during fermentation were studied.The results show that the fermentation effect was better when the ratio of Lactobacillus to Staphylococcus was 1:1.The combined fermentation of L.sakei+S.carnosus and P.pentosaceus+S.carnosus accelerates the decline of sausage p H,Aw and holding water and accelerates fermentation.At the same time,the color of the sausage(a-value)was significantly higher than that of the KB group when add the L.sakei+S.carnosus and P.pentosaceus+S.carnosus,which significantly improved the sensory score.In addition,the Enterobacter in the product is not detected after compound fermentation,which greatly ensuring the safety of the product.The results of electronic nasal flavor analysis showed that the sausage flavor had a large relationship with fermentation time,and the composite fermentation of L.sakei+S.carnosus and P.pentosaceus+S.carnosus was not very different from that of KB.Explain that the use of L.sakei+S.carnosus and P.pentosaceus+S.carnosus composite fermentation can be processed to produce sausages with similar flavors to natural fermentation,but can significantly improve the quality of the product,improve product safety,and ensure product quality.