Study On Direct Vat Set Lactobacillus Fermentation Lemon Sauerkraut

Pickled vegetables for their distinctive fermentation flavor,has become the Northeast winter the most popular traditional food of the people.At present,most of the preserved by fermentation of traditional methods,and the method is relatively simple.The main food is cooking,so there is a big research space in the research and development of the pickled cabbage this experiment mainly to.Chinese cabbage and fresh lemon as raw material.The lactic acid bacteria fermentation method for salting out.Traditional pickled vegetables flavor through the special aroma of fresh lemon is improved.At present,the research fruit of pickled vegetables and their products is relatively small.Therefore,the fermentation process of this experiment is to study the citric acid pickled cabbage.The main research contents and conclusions are as follows:(1)The screening of Streptococcus thermophilus,through single factor test and response optimization of Streptococcus thermophilus fermentation DVS surface method protective agent formula,the optimization results of 5.58% lactose,peptone 6.27%,7.73% trehalose,preparation of starter cell survival rate can reach 77.85 + 1.46%.stored for 8 weeks under the condition of 4 DEG C,direct viable count of Streptococcus thermophilus fermentation agent has been maintained at more than 1010cfu/g.(2)Optimization of the proliferation medium of lactic acid bacteria.Based on the single factor experiment of basic culture medium,nitrogen source,carbon source and growth factor,the key factors affecting the proliferation of two strains were determined by Plackett-Burman experiment design,and the factor level was optimized by response surface methodology.(3)Through the single factor experiment was conducted to study the effects of fermentation conditions on citric acid texture.With temperature,salt concentration,inoculation ratio and cabbage lemon factors,total acid,hardness and sensory scores as evaluation index,the four factors and three levels orthogonal test,the optimum fermentation conditions for 10% inoculation amount,temperature 25 0C,salt 2%,citric acid fermentation of cabbage than 1:7,total 7d pickled cabbage is 1.021%;the hardness is 43.0N,the sensory score of 86 points.According to the conditions of fermentation of citric acid,the index values were hardness 49.2N,chroma 77.65,pH was 3.49,1.09% of total acid,the sensory score is 90.(4)A comparative study of citric acid and traditional sauerkraut.Compared the fermentation process of physicochemical index and micro ecological changes: citric acid production and fermentation to lactic acid accumulation,25 DEG C after the fermentation of 9D pH and total acid were 3.2 and 1.292%;citric acid-reducing VC acid is lower than that of the traditional food fermentation,5D after higher than traditional fermentation;citric acid fermentation in the whole fermentation process of texture and color are maintained at a high level,after the fermentation of 9D hardness of 39.8N,chroma is 72;fermentation mature low content of nitrite,fluctuation at about 0.6mmg/kg.