The Study On Multiplication Culture Of LAB In Fermented Meat And Processing Of DVS

Fermented meat is nutritious,flavored and upscale with long shelf-life,which constitutes an important aspect of modern meat products.However at present,our country industrialization production of fermented meat products by using microbial starter cultures are dependent on imported from abroad,which restricts the scale of fermented meat production in China.In this paper,we used LAB in fermented meat which preserved in our lab as seed strains to explore the multiplication culture conditions of the strains and select efficient multiplication medium,preparing high-quality DVS.The main content includes the following several aspects:1.The selection of basic multiplication mediumAccording to laboratory preservation of LAB as the research object,through the optimization of the initial pH,carbon source,nitrogen source,buffer agent and nutritional factor,selecting the efficient proliferation medium meat LAB fermentation:initial pH6.2,2%sucrose,2%yeast extract,2.5%buffer agent A?Na₂HPO₄/KH₂PO₄?,10%potato juice.2.The selection and optimization of strain microcapsule formulaMicrocapsule can ensure that the bacteria in the process of training to obtain the necessary nutrients,and also isolate harmful material from the culture,make the bacteria to grow better.Through the optimization of wall material ratio,core and wall material ratio,tackifier concentration,CaCl₂ concentration,select the most optimal microcapsule formula:wall material ratio 1:1,core and wall material ratio 1:2.9,8%tackifier concentration,3.5%CaCl₂ concentration.In this condition,we did three validation tests to confirm the predictive value,which we got the average embedding rate for 93.62%.3.The collection of strains and preparing of DVSAfter the multiplication culture strains were broken capsule and centrifugal collection,collecting bacterium vacuum freeze drying of clay mixed with some protective agent,and optimize the protectant formula,high quality direct investment type starter is prepared.The optimized conditions of centrifugal collection:the temperature of the centrifugal 0?,the centrifugal rotational speed 3000rpm,the centrifugal time 10min.The protective agent formula is:0.8ml/L Tween 80,15g/L Vc,15g/L MSG.The protective agent mixed with bacteria mud in a ratio of 3:1 to freeze drying,validation test,the viable count in the bacterial powder is 1.45×10¹¹cfu/g,the concentration of bacteria than the original powder3.23 x 10⁹cfu/g for 45 times up.