Preparation Of The Lactobacillus Plantarum Of Direct-vat-set Starter And Application In Fermented Fish

In this research, lactobacillus plantarum was chosen as investigative bacteria. Spray drying method and vacuum freezing drying method were used by mading the lactobacillus plantarum of direct-vat-set starter culture. Optimum condition of lactobacillus plantarum of direct-vat-set starter culture was studied. Both methods had been compared. Obtain the optimum method. Finally, the lactobacillus plantarum of direct-vat-set starter culture was made by the optimum method was applied in carp. To prepare the fermented fish products.Lactobacillus plantarum was chosen as main research object. MRS liquid medium was used to cultivate the lactobacillus plantarum. Bacterial growth curve and acid yield curve, bacterial of heat resistance,bacterial resistance to acid, bacterial of salt tolerance and storage, the best conditions of centrifugal, and the biocompatibility of the wall material and lactobacillus plantarum were measure. Bacterial species survival rate was chosen as indicators. Spray drying method mading the lactobacillus plantarum of direct-vat-set starter culture was optimized by single-factor and orthogonal array design methods. Results showed that lactobacillus plantarum heat resistance was not strong. The appearance of a large number of death above60℃. Lactobacillus plantarum can tolerate6%NaCl solution, and had the strong ability of acid. The best condition of centrifugal was6000r/min,10min of concentrated bacterial suspension. Bacterial rate was higher. Bacterial species survival was93%. The best condition of mading the lactobacillus plantarum of direct-vat-set starter culture by spray drying method was wall material concentration35%, the proportion of wall materials (arabic gum:maltodextrin)1:9, the amount of skim milk powder1.5%, inlet temperature160℃, outlet temperature87℃, feed rate45mL/min, solids content27%. Under this condition, bacterial species survival rate was41.28%. The viable bacterial counts of the lactobacillus plantarum of direct-vat-set starter culture were1.21×106CFU/g. Preserving three months in4℃, the bacterial counts were2.11×105CFU/g.Lactobacillus plantarum was chosen as main research object. MRS liquid medium was used to cultivate the lactobacillus plantarum. Lyophilization survival rate was chosen as indicators. Vacuum freezing drying method mading the lactobacillus plantarum of direct-vat-set starter culture was optimized by single-factor and orthogonal array design methods. Both methods had been compared. Bacterial species survival rate, storage test, viable bacterial counts were used to make sure the best condition of mading the lactobacillus plantarum of direct-vat-set starter culture. Results showed that bacterial freeze drying protective agent were skim milk powder12%, ascorbic acid1.5%, glucose3%, lactose6%. Under this condition, lyophilization survival rate was65.32%. The viable bacterial counts of the lactobacillus plantarum of direct-vat-set starter culture were2.32*109CFU/g. Preserving three months in4℃, the bacterial counts were5.59×108CFU/g, still above1×108CFU/g. Bacterial species survival rate was higher. It was beneficial to be used in the large scale production. Comprehensive comparison of two ways from bacterial species survival rate, storage test, viable bacterial counts were all higher. Therefore, vacuum freezing drying method was used by mading the lactobacillus plantarum of direct-vat-set starter culture was the optimum method.Lactobacillus plantarum was chosen as main research object. MRS liquid medium was used to cultivate the lactobacillus plantarum. Vacuum freezing drying method was used in mading the lactobacillus plantarum of direct-vat-set starter culture. The lactobacillus plantarum of direct-vat-set starter culture was applied in carp. To prepare the fermented fish products. Sensory score and pH was chosen as indicators. Fermented fish products were optimized by single-factor and orthogonal array design methods. Results showed that white granulated sugar was2%, salt was4%, starter culture was3%, fermentation time was24h, fermentation temperature was35℃. In the finished product, sensory score was93.8, moisture content was57.35%, pH4.60. Fermented fish products were moderate sour, soft texture, flexible, shiny, hazel, uniform color, don’t fishy smell, aromatic. The lactobacillus plantarum of direct-vat-set starter culture was used. Not only improved the survival rate, increase the ecomomic efficiency, easy to using, easy to preserving, but also facilitated to large-scale production of fermented meat products.