Can a filter really sterilize a solution??

[Cornellius]

I´m no chemical master here, but it makes me hard to believe that filtering a solution (fina) can let it sterile....I think that bacteria can pass thru the filter.....heat is the only way to kill them. Am I right??

 

[ragin']

dont know, to the top.

 

[Andy13]

The pore size is smaller than the average bacterium... Spores will slip through, though.

 

[cockdezl]

I used to use a 0.45 micron sterile filter to sterilize biochemical media for microbiological testing. This was the recommended pore size for filter sterilization in the industry. I never had any problems with contamination. The use of a 0.22 micron filter will increase the effectiveness of sterilization.

Most common bacteria are around 1-2 microns in length and around 0.4-1.0 microns in width. Haemophilis influenzae and Mycoplasmas are smaller, but not as prevalent. Also, viruses and toxins will not be filtered out.

Heating the solution after filtering is the best treatment for ensuring sterility. Do two heat treatments at around 250 degrees for about 30 minutes, with a cooling period in between (around 2 hours). This will allow for sporulated organisms to vegetate, and the second heat treatment will kill these vegetative cells.

 

[ColumboWeiser]

That is why we heat the solution a few times...

 

[Zyglamail]

as cockdezl mentioned the kits usually come with .45 filter. For my current batch I also have a .22 filter I am going to use as a final pass. I have not heard of anyone having probs with the kits and post conversion baking.