Effect of culture medium and cryoprotectants on the growth and survival of probiotic lactobacilli during freeze drying.
OBJECTIVE
To investigate the effects of the medium and cryoprotective agents used on the growth and survival of Lactobacillus plantarum and Lactobacillus rhamnosus GG during freeze drying.


RESULTS
A complex medium was developed consisting primarily of glucose, yeast extract and vegetable-derived peptone. Trehalose, sucrose and sorbitol were examined for their ability to protect the cells during freeze drying. Using standardized amount of cells and the optimized freeze drying media, the effect of the growth medium on cell survival during freeze drying was investigated. The results showed that glucose and yeast extract were the most important growth factors, while sucrose offered better protection than trehalose and sorbitol during freeze drying. When the cells were grown under carbon limiting conditions, their survival during freeze drying was significantly decreased.


CONCLUSIONS
A clear relationship was observed between cell growth and the ability of the cells to survive during the freeze drying process.


CONCLUSIONS
The survival of probiotic strains during freeze drying was shown to be dependent on the cryoprotectant used and the growth medium.
Siaterlis
A
A
Department of Food Biosciences, The University of Reading, Berkshire, Reading, UK.
Deepika
G
G
Charalampopoulos
D
D
D001431:Bacteriological Techniques; D003451:Cryoprotective Agents / Q000494:pharmacology*; D003470:Culture Media; D005612:Freeze Drying / Q000379:methods*; D007778:Lactobacillus / Q000145:classification / Q000187:drug effects / Q000254:growth & development; D048191:Lactiplantibacillus plantarum / Q000187:drug effects / Q000254:growth & development; D052201:Lacticaseibacillus rhamnosus / Q000187:drug effects / Q000254:growth & development; D019936:Probiotics
D003451:Cryoprotective Agents; D003470:Culture Media