The invention discloses a process for performing frozen separation on
lactic acid bacteria and making
dry powder. The process comprises the following steps: S1, preparation of sample bacterial liquid:
cutting a
lactic acid bacteria source sample into pieces, performing
grinding, performing transferring into a centrifugal tube filled with 9 mL of
sterile water or normal
saline, performing shaking by using a vortex or a shaking table, performing uniform mixing for 10-30 minutes, namely diluting 10 <-1 > sample liquid, and continuously diluting the sample to 10 <-3 >, 10 <-4 > and 10 <-5 >; and S2, culture of
lactic acid bacteria colonies: respectively sucking 0.2 mL of the 10 <-3 >, 10 <-4 > and 10 <-5 > sample solutions in the step S1,
coating an
MRS agar culture medium with the sample solutions, performing operating according to three plates in each gradient, and performing culturing for 24-48 hours at the temperature of 37 DEG C to obtain required lactic acid bacteria colonies. According to the invention, the
MRS agar culture medium is coated with the bacterial liquid, the
MRS agar culture medium contains a specific content of a freeze-
drying protective agent compounded by glucose, peptone, a
yeast extract and the like, and in addition, a vacuum-
nitrogen charging
grinding and crushing technology after freeze-
drying is combined, so that the freeze-dried
powder can be effectively prevented from absorbing
moisture in the environment in the crushing process.