Vials used for freeze drying should always be made of glass. Atmospheric water can diffuse into plastic tubes and damage freeze dried samples. Furthermore, samples are safest when sealed under vacuum in glass ampoules or tubes.

I have seen cultures in freeze dried 'bags' of laminated foil, similar to the way I have seen freeze dried coffee in the supermarkets (look like little hard bricks until you break the vacuum). But I suppose you would have to have an entire packaging system set up to do that; the glass vial/ampoule method is the most available or widely used method.  You can do a manual setup of a manifold system that has thin pencil-like ampoules connected to stop-cocks (1 vacuum source, a manifold with many branches, each with a stop-cock that can cut off the vacuum so when the individual vials are detached, the vacuum to the others is not released).  Some people have used ceramic beads (that you get from a hobby store to make beads-on-a-string) that are porous and autoclavable, they place 10-15 of these in the bottom of a pencil-like ampoule, add about 100-200 ul of culture concentrate [centrifuge a culture, and resuspend with a minimal amount (1/10th?) of fresh media or cyroprotectant], place on the vacuum manifold....assuming you have multiple tubes....when one has been dried, then close the valve to that individual tube (still under vacuum), use a torch to flame the neck of the thin tube and slowly twist as it starts to melt, and then you can break it away as you pull away. Twisting helps insure the seal.  When you need them, you break the tip and pour out one of the beads into media.  The two example photos are one without individual valves and the other you can see the valves on each ampoule.  The first is risky, if you flame the tube in such a way that the remaining piece is not sealed, it release the vacuum to all the other tubes.  I like the method with the shut off valve on each indivudal tube.

http://www.hpcimedia.com/images/website/ManChemTechnical/DIR_14/F_19349.jpg

http://www.pnas.org/content/98/24/13501/F1.large.jpg

Hi,

You can freeze dry LAB on stainless steal trays and pack the powder in aluminium layered plastic. But you shoud again pack your sample in a packaging with low O2 permeability.

Additionaly the desired shelf life is important. If you want to use it as a starter culture I would recomend you to store the liyophilised sample at -18 for up to  2 years. Or you could store it at +4 C at a litle bit higher risk of decreasing activity.

Actually I am interested in using a freeze dried 'bags' of laminated foil (in sachet form) since the LAB will be use for food application. But I am still looking for a method to do it. Do we actually need a specific machine to do it? Does anyone have experience in this? After we freeze dried the LAB in the sachet, how do we seal it?

Hi, I have a similar problem. It is going to be difficult for me to take out the centrifuged materials using a refrigerated centrifuge unless dried.

And I'm concern if centrifuge can have negative effect on my plastic vail or not.

Anyone with experience, please.

I tried it and it worked.