The invention relates to the technical field of microbial preparations, and discloses a
lactobacillus plantarum microbial preparation as well as a preparation method and application thereof, and the
lactobacillus plantarum microbial preparation is prepared by mixing
lactobacillus plantarum wet bacterial
sludge and composite protective matrix liquid and then performing vacuum
freeze drying. The composite protection matrix liquid comprises
trehalose, soluble soybean
polysaccharide, L-
sodium ascorbate,
calcium lactate pentahydrate and
sodium citrate dihydrate. The preparation method comprises the following steps: adding
anhydrous betaine into
fermentation liquor in the later period of
fermentation, carrying out programmed cooling, and collecting bacterial
sludge; mixing and redissolving the bacterial
sludge and the matrix liquid, and then carrying out
nitrogen shearing gas stripping; and then freeze-
drying through a procedure including annealing treatment to obtain a finished product. According to the invention, through cooperation of wrapping of the
polysaccharide-
calcium microgel network and compatible solute regulation of
intracellular accumulated
betaine, ice
crystal nucleation and
dehydration shrinkage damage in the freeze-
drying process are relieved, the
survival rate of freeze-
drying viable
bacteria of the microbial preparation is improved, and the storage stability of the microbial preparation in subsequent
probiotic food application is improved.