Lactobacillus casei AHU 1055 및 Lactobacillus acidophilus JAM 1043의 凍結乾燥와 生存率에 關한 硏究 = Studies on Freeze-Drying and the Survival Rate of L. casei AHU 1055 and L. acidophilus JAM 1043

다국어 초록 (Multilingual Abstract)

In order to find the most suitable conditions of freeze-drying for the long term preservation of lacto-bacillus casei AHU 1055 and Lactobacillus acidophilus JAM 1043, the growth phase, the cryoprotection medium and inoculum size have been studied.
The results obtained in this study are summerized as follows :
1. L. casei AHU 1055 and L.acidophilus JAM 1043 reached to stationary phase after incubating at 37˚C for 16hrs and 12hrs in MRS broth, respectively.
2. The highest viability of each strains was obtained in 11% skim-milk for L. casei AHU 1055 and 9% skim-milk for L. acidophilus JAM 1043 as basic cryoprotection medium.
3. The complex medium contained 11% skim milk powder, 2.5% arginine and 3% glucose was the best suspending midium for freeze-drying of L. casei AHU 1055, and the medium contained 9% skim milk powder, 7% glycerol, 9% lactose, 0.5% arginine was the best suspending medium for freeze-drying of L. acidophilus JAM 1043.
4. The strong positive correlation was found between inoculum size and the survival rate in both strains.
5. When the tested strains were cultured and freeze-dried under the best optimal conditions, the survival rates of freeze- dried L. casei AHU 1055 and L. acidophilus JAM 1043 were 85.8% and 84.0%, respectively.