double filtering

[Kymel]

I am scared as fuck that I might end up with staph on my first brew, so I come to ask about double filtering. I was thinking going .45 to .2 to avoid any chance of staph, but I read that staph can actually get through .2 pores. is there any other way to avoid it? Can you do it with smaller filters like .1 um? is double filtering a good idea?

 

[alphastrength50]

.2 is perfect bro and if ur super paranoid bake it. honestly the human body is so much more stringer than one knows. it truly is amazing

 

[heavylifter87]

I think .45 is fine that's all I do never had problems ...

 

[WesternWay]

The BA should take care of anything bad.

 

[Kinikuman]

.22 is the filter standard for companies like Roche and Bayer. Between the filter and the BA you really should not have any issues.

 

[Docd187123]

Filtering with a .45 before a .22 won't do anything except allow filtering of the .22 faster. There's really no added benefit of filtering it with the larger filter first unless you're raws have lots of contaminants. No need to double filter it either.

The BA and filtering is enough and if you're worried pressure cook the gear. Do not bake it though.

 

[rutman]

The BA should take care of anything bad.

Not really.......

The only thing the BA will do is to keep anything from forming in the vial. It will not kill existing bacteria... Filtering is the only thing that will remove it.

 

[Docd187123]

Not really.......

The only thing the BA will do is to keep anything from forming in the vial. It will not kill existing bacteria... Filtering is the only thing that will remove it.

BA will kill bacteria after several days. It won't remove anything from the solution but it will still kill off bacteria

 

[Kymel]

alright, cool and any suggestions on what kind of pressure cooker to get?

 

[Kymel]

http://www.bedbathandbeyond.com/sto...V7c0_c4Nu1uKpvzNVw7JvuyaIBOlbXxqSQxoCCALw_wcB should be fine right?

 

[Ultimatepip]

Autoclave?

 

[Docd187123]

A pressure cooker that goes up to 15PSI

 

[Jeep187]

@Docd187123 You've mentioned using a pressure cooker. You said to get one that goes to at least 15psi. How long do you cook the gear for and do you need to vent it with a needle.

 

[Docd187123]

No, if you vent while pressure cooking you defeat the purpose of oressure cooking by letting in outside contaminants. When you fill and cap your vial or fill a sealed sterile vial just fill it to the specs ie 10ml vial fill 10ml. There will be enough headspace left for volumetric expansion.

I do 1-2hrs in the pressure cooker. You need to place the vials in something inside the pressure cooker. Like a stand. You don't want any part of the vials submerged in water.

 

[Jeep187]

No, if you vent while pressure cooking you defeat the purpose of oressure cooking by letting in outside contaminants. When you fill and cap your vial or fill a sealed sterile vial just fill it to the specs ie 10ml vial fill 10ml. There will be enough headspace left for volumetric expansion.

I do 1-2hrs in the pressure cooker. You need to place the vials in something inside the pressure cooker. Like a stand. You don't want any part of the vials submerged in water.

Thanks brother

 

[Kymel]

aren't autoclaves like expensive?

 

[Kymel]

also doc, can you provide maybe some visual aids on how this pressure cooking technique is done?

 

[tanuki]

From personal experience filtering once with a 45 and never a problem.

If there was staph infections you'd hear about it more often, but you don't.

I suspect some labs don't even filter nor do they have actual product. So people are injecting cooking oil. Never been a problem.

 

[rutman]

From personal experience filtering once with a 45 and never a problem.

If there was staph infections you'd hear about it more often, but you don't.

I suspect some labs don't even filter nor do they have actual product. So people are injecting cooking oil. Never been a problem.

All I've ever used is a 45 Whatman...

 

[Casshern001]

No, if you vent while pressure cooking you defeat the purpose of oressure cooking by letting in outside contaminants. When you fill and cap your vial or fill a sealed sterile vial just fill it to the specs ie 10ml vial fill 10ml. There will be enough headspace left for volumetric expansion.

I do 1-2hrs in the pressure cooker. You need to place the vials in something inside the pressure cooker. Like a stand. You don't want any part of the vials submerged in water.

This is something that always seemed a little off to me. When using pre-sterilized/sealed vials, would the pressure inside the cooker not force steam (water) into the vials through the punctures created by the needles used to fill them? I know they basically seal off when the needle is removed, but there's still going to essentially be a hole/weak spot there for the pressure to equalize, no?

Or are vial stoppers really that good at self sealing? This study does seem to indicate they are pretty amazing, unrelated to pressure differentials though.

http://www.ncbi.nlm.nih.gov/pubmed/23636157