Sterilization of Test Brew

[HereToTeachAndLearn]

@HereToTeachAndLearn
Please post the textbook references, I am curious.
As far as I know the pressure in the autoclave is just the mechanism to achieve boiling water with 121 degrees. The steam and heat conduction of 121 degrees do the actual sterilisation by killing the microbes. Hence why you could also use a pressure cooker.

Methods of Sterilization

The five basic methods of sterilization are moist heat, dry heat, chemical use, filtration,
and radiation. Of these, moist heat, dry heat, some forms of chemical sterilization, and
filtration are appropriate for pharmacists to use. Pharmacists can, however, use contract
facilities for gaseous and radiation sterilization. A pharmacy should validate all of its ster￾ilization methods on a regular basis; the routine use of devices or kits that indicate sterility
is recommended. Heat is the most reliable method of sterilization. The efficiency of heat
in destroying microorganisms is dependent on temperature, time, moisture, and pressure.
Both moist-heat and dry-heat sterilization processes are used.

Moist-Heat Sterilization

In moist-heat sterilization (steam under pressure), an autoclave provides a saturated steam
environment, typically 121°C at 15 psi, with variation depending on the autoclave being
used. After the correct temperature and pressure are reached, the sterilization process con￾tinues for an additional 20 minutes, at which time the pressure and temperature are allowed
to return to ambient levels at a rate depending on the load of items in the autoclave.
The saturation of water, or steam, at high pressure is the foundation for the effectiveness
of moist-heat sterilization. When steam makes contact with a cooler object, it condenses and
loses latent heat to the object. Under autoclaving conditions, the amount of energy released
is approximately 524 cal/g, whereas 1 cal/g of energy is released in dry-heat sterilization. The
difference explains why moist heat under pressure is more effective than dry heat at the same
temperature in destroying microbial life. It also helps explain why objects or preparations to
be sterilized in an autoclave must contain water or permit saturated steam to penetrate and
make contact with all surfaces to be sterilized. Air pockets are of great concern in the steam
sterilization process because the steam must reach all sites to be effective.
Sealed containers must contain water in order to be sterilized by this method. Sealed,
dry containers will reach only 121°C inside, and the heat will not be moist; thus, steriliza￾tion will likely not occur. Similarly, anhydrous and oily solutions that contain no water will
reach only 121°C and the heat will be dry. To sterilize glycerin in sealed containers, about 1%
sterile water for injection can be added before the autoclaving process. Moist-heat steriliza￾tion is the desired method of sterilization for any item that can withstand high temperatures,
including rubber closures, high-density plastic tubing, filter assemblies, sealed-glass ampuls
containing solutions that can withstand high temperatures, stainless-steel vessels, gowning
materials, and various hard-surface equipment items.

Dry-Heat Sterilization

Dry-heat sterilization requires heat in excess of that produced by autoclaving and involves
the use of a high-temperature oven. The following operating conditions have been estab￾lished: at 160°C, 120 to 180 minutes; at 170°C, 90 to 120 minutes; and at 180°C, 45 to
60 minutes. However, pharmacists should not assume that any of the three conditions
will automatically suffice for all formulations; sufficient time at the various temperatures
must be determined to achieve the desired sterilization. Dry-heat sterilization is used to
sterilize glass, stainless steel, and other hard-surface materials, as well as dry powders not
labile to high temperatures. Injectable oily solutions also can be dry-heat sterilized if the
active ingredient remains potent and stable; a time and temperature cycle that produces a
validated finished sterile preparation must be used.

The Art, Science, and Technology of Pharmaceutical Compounding

FIFTH EDITION
Loyd V. Allen Jr., PhD

 

[Nuvo6]

I kind of doubt that a cheaper filter would put more stuff in

Thats like saying the cheap chinese no name filter should have given you an infection because it would have added more junk to what should have been sterile.


but I am trying it out. maybe I can change the whatman out every 160ml instead of 90-100

I don't think it'll last 160ml my brother. They are rated at 100 but only last me half at most. I usually change them at 30-40ml because they slow down

 

[Spaceman Spiff]

I don't think it'll last 160ml my brother. They are rated at 100 but only last me half at most. I usually change them at 30-40ml because they slow down

I have definitely pushed it to 100 with the caulking gun. no breks, just slows

I can make about 8-9 vials within an hour. thats just me giving it a few pushes and walking away.

I can tell its going bad by the drip rate

 

[1cyclewonthurt]

Methods of Sterilization

The five basic methods of sterilization are moist heat, dry heat, chemical use, filtration,
and radiation. Of these, moist heat, dry heat, some forms of chemical sterilization, and
filtration are appropriate for pharmacists to use. Pharmacists can, however, use contract
facilities for gaseous and radiation sterilization. A pharmacy should validate all of its ster￾ilization methods on a regular basis; the routine use of devices or kits that indicate sterility
is recommended. Heat is the most reliable method of sterilization. The efficiency of heat
in destroying microorganisms is dependent on temperature, time, moisture, and pressure.
Both moist-heat and dry-heat sterilization processes are used.

Moist-Heat Sterilization

In moist-heat sterilization (steam under pressure), an autoclave provides a saturated steam
environment, typically 121°C at 15 psi, with variation depending on the autoclave being
used. After the correct temperature and pressure are reached, the sterilization process con￾tinues for an additional 20 minutes, at which time the pressure and temperature are allowed
to return to ambient levels at a rate depending on the load of items in the autoclave.
The saturation of water, or steam, at high pressure is the foundation for the effectiveness
of moist-heat sterilization. When steam makes contact with a cooler object, it condenses and
loses latent heat to the object. Under autoclaving conditions, the amount of energy released
is approximately 524 cal/g, whereas 1 cal/g of energy is released in dry-heat sterilization. The
difference explains why moist heat under pressure is more effective than dry heat at the same
temperature in destroying microbial life. It also helps explain why objects or preparations to
be sterilized in an autoclave must contain water or permit saturated steam to penetrate and
make contact with all surfaces to be sterilized. Air pockets are of great concern in the steam
sterilization process because the steam must reach all sites to be effective.
Sealed containers must contain water in order to be sterilized by this method. Sealed,
dry containers will reach only 121°C inside, and the heat will not be moist; thus, steriliza￾tion will likely not occur. Similarly, anhydrous and oily solutions that contain no water will
reach only 121°C and the heat will be dry. To sterilize glycerin in sealed containers, about 1%
sterile water for injection can be added before the autoclaving process. Moist-heat steriliza￾tion is the desired method of sterilization for any item that can withstand high temperatures,
including rubber closures, high-density plastic tubing, filter assemblies, sealed-glass ampuls
containing solutions that can withstand high temperatures, stainless-steel vessels, gowning
materials, and various hard-surface equipment items.

Dry-Heat Sterilization

Dry-heat sterilization requires heat in excess of that produced by autoclaving and involves
the use of a high-temperature oven. The following operating conditions have been estab￾lished: at 160°C, 120 to 180 minutes; at 170°C, 90 to 120 minutes; and at 180°C, 45 to
60 minutes. However, pharmacists should not assume that any of the three conditions
will automatically suffice for all formulations; sufficient time at the various temperatures
must be determined to achieve the desired sterilization. Dry-heat sterilization is used to
sterilize glass, stainless steel, and other hard-surface materials, as well as dry powders not
labile to high temperatures. Injectable oily solutions also can be dry-heat sterilized if the
active ingredient remains potent and stable; a time and temperature cycle that produces a
validated finished sterile preparation must be used.

The Art, Science, and Technology of Pharmaceutical Compounding

FIFTH EDITION
Loyd V. Allen Jr., PhD

Thank you. Great read.
However, it makes me think if it would be possible to achieve sterilization by
cooking the vial for longer since the temperature remains 121 C but misses the efficacy of the steam heat conduction, and/or add 1% sterilized water like in the example with glycerine. However water and oil don't mix so you'd have a floater I imagine.