Baking Bottles

[caleb]

For my last two bottling batches, I decided to bake the bottles in the oven instead of using sanitizing chemicals.

I just stacked them in, set the oven to 95 degrees, and when it was hot enough, let them bake for one hour. Once done, I left them for a few hours to cool down (with the door closed). Then just remove, prime, fill, cap.

Brilliant. It is SO much easier than using chemicals, and they should in theory be totally sterilized, so more effective as well. I love it.

Only down side is that I can only fit 19 longnecks in my oven, so I had to do a few "conventionally".

However, I think my new method from now on will be:
* Once used, bottles will be given a good rinse with hot water to clean.
* Clean bottles will get capped with a small piece of aluminium foil to keep things out.
* One I have 19, they will be baked in the oven to sterilize.
* These sterilized bottles will then be stored away, with foil cap in place.
* Come bottling time, I just take however many bottles I need out of storage, remove foil and I'm underway.

Does anyone else do it this way?

 

[raven19]

Not for me, it must take a while to let them cool down - but if it works then beers to you!

:icon_offtopic: I did see some tomato sauce being made on a tv show the other week where they actually bottled it then boiled all the filled & capped bottles after capping. I couldnt believe it! Bit different for our precious beer though...

 

[peas_and_corn]

For those who bake their bottles- I have a fan force oven, would this pose an issue regarding sanitation? The fan stays on for a while after the oven is turned off.

 

[Effect]

For those who bake their bottles- I have a fan force oven, would this pose an issue regarding sanitation? The fan stays on for a while after the oven is turned off.

probably be better...keeps the temperature throughout the oven basically constant - i.e. it reduces the hot spots like 95% or so.

 

[apd]

Does anyone else do it this way?

Caleb,

I'm a bottle baker too. One less task to do on bottling day.

I bake mine at about 110*C for 10-15 minutes.

Andrew

 

[Thirsty Boy]

However, I think my new method from now on will be:
* Once used, bottles will be given a good rinse with hot water to clean.
* Clean bottles will get capped with a small piece of aluminium foil to keep things out.
* One I have 19, they will be baked in the oven to sterilize.
* These sterilized bottles will then be stored away, with foil cap in place.
* Come bottling time, I just take however many bottles I need out of storage, remove foil and I'm underway.

Does anyone else do it this way?

Exactly how I have sanitised every bottle for the past several years - keep on top of it, dotn do a sanitising run just before you want to bottle, then its a pain in the bum. Every time you get an oven tray's worth of empties... then sanitise them with the foil and store them. You never have more than a dozen or so bottle that are both empty and unsanitised and you are right to go anytime you want.

I give them a good old blast though - into the oven at low for 30 min, up to medium for 30, then up to 180-200C for 30-60. Dry heat sterilization is much less effective than steam/pressure. I don't think for instance that Andrew's 110C for ten minutes, nor your 95 for an hour is long enough or hot enough to be sure that things are properly dead.

 

[pb unleaded]

Just a thought, but can you sanitize bottles in a microwave, maybe for about 30 secs?

 

[Jase71]

Just a thought, but can you sanitize bottles in a microwave, maybe for about 30 secs?

If the bottles are dry, I don't see how it would serve any purpose. My understanding is that a microwave oven heats food due to radiowaves corresponding to the resonant frequency of water molecules, creating friction, thus heating your food.

Now I'll no doubt be shot down with that amateurish explanation, but its been years since I studied all this sort of stuff

To answer your question, Arthur, I would say 'No'

 

[unterberg]

From Wiki:

Dry heat can be used to sterilize items, but as the heat takes much longer to be transferred to the organism, both the time and the temperature must usually be increased, unless forced ventilation of the hot air is used. The standard setting for a hot air oven is at least two hours at 160 C (320 F). A rapid method heats air to 190 C (374 F) for 6 minutes for unwrapped objects and 12 minutes for wrapped objects.^[6][7] Dry heat has the advantage that it can be used on powders and other heat-stable items that are adversely affected by steam (for instance, it does not cause rusting of steel objects).

Thats what we do with glass bottles in the lab - clean, put aluminium foil over the lid and bake at 175C for and hour.

Microwave should in principle work since you will get the water molecules to boil. But I dont think its very practical. Probably would have to microwave for quite a long time and some bacteria have spores that hardly contain any more water.
Stick with the oven.

 

[haysie]

for mine the oven is a no brainer, a simple rinse in water too get any crud off the bottom, collect in my case about 20 tallies, chuck em in the oven at 200 for 75, foil em n jobs done. no brushes chem`s or elbow grease. I cant fit tallies standing up in my microwave!

 

[threeheads]

Does anyone ever get any broken bottles?

I am sitting here contemplating having to wash bottles and am interested to know more.

 

[caleb]

I give them a good old blast though - into the oven at low for 30 min, up to medium for 30, then up to 180-200C for 30-60. Dry heat sterilization is much less effective than steam/pressure. I don't think for instance that Andrew's 110C for ten minutes, nor your 95 for an hour is long enough or hot enough to be sure that things are properly dead.

The 95C for 1 hour comes from the wonderfully rambling "Brewer's Handbook" by G. Noonan, M. Redman and S. Russell.

200 for up to 1 hour sounds pretty hot! Nothing ever exploded?

 

[Thirsty Boy]

no... but remember I take three steps to get there increasing from low to med to finish on high: 180-200 is a range because my oven is crap and I strongly suspect it doesn't actually get to 200C - you MUST NOT open the door till things have completely cooled down. Bottles will crack.

I put the foil cap on before I bake em.. then they are basically sterile indefinitely till the foil is breached or removed

 

[haysie]

200 for up to 1 hour sounds pretty hot! Nothing ever exploded?

in my case, no. i use thin crappy hand me down melbourne bitter bottles along with a couple of batches of HBS 650ml bottles, thus far all is well. Probably more of a crackle than an explosion at the very worst.

 

[Rodolphe01]

I can't recall exactly the time and temps, but when I did microbiology at uni we were taught dry heat was a really crap way of sterilising compared with steam/pressure... I'm sure the times were in excess of an hour and temps nearing 200, of course no one would ever autoclave their bottles though. Having said that, people use the word sterlise a lot, when they actually mean sanitise.

But by the sounds of other peoples experience it appears to be good enough for brew. I might give it a go, Thirsty Boy's trick seems good, do it every time you have accumulated an ovens worth of bottles and store them sanitised.

My current bottle sanitising regime is just a rinse with water after drinking (or within the next day or 2) and on brew day just use some no-rinse sanitiser... Not exactly laborious as I don't use brushes etc.

 

[hoppinmad]

Does anyone ever get any broken bottles?

I am sitting here contemplating having to wash bottles and am interested to know more.

Well.... funny you should ask that.... I almost laugh when I think about the incident

I have always baked my bottles. 200c for 20mins.

First time I did it (about 10 years ago when I was a silly young uni student) I started pulling them out with an oven mit (whilst still hot) and putting them on the chopping board. Unfortunately the chopping board had a small drop of water on it that I didn't see... so guess what happens next.....

The bottle cracked into a million little pieces... but interestingly still maintained its bottle form. So I had a bottle sitting on the chopping board that I knew would collapse all over the bench if I moved it. It looked pretty cool actually... but not exactly safe

Of course now I never take them out of the oven until they are cool enough to touch

 

[newguy]

Microwave ovens won't sterilise anything unless there is water present.....and no, the water in bacteria themselves isn't enough. As others have said, microwave ovens bombard the food with radio waves (2.45 GHz) which causes the water in the food to sympathetically vibrate (think fat opera singer breaking a glass when she hits the right note), which in turn heats the food. Running the oven "dry" doesn't achieve any heating and is very bad for the oven.

 

[kram]

* Once used, bottles will be given a good rinse with hot water to clean.

I only ever did this step and another rinse with hot water prior to bottling. They were on semi high rotation so they weren't stored (upside down) too long.

I keg now and if I bottle from the keg i'll napisan then iodophor.

 

[King Brown]

Have been considering doing this for quite a while, only thing holding me back is my crappy convection oven. Will definately give it a try when I get a bigger place with a bigger oven

 

[Thirsty Boy]

I can't recall exactly the time and temps, but when I did microbiology at uni we were taught dry heat was a really crap way of sterilising compared with steam/pressure... I'm sure the times were in excess of an hour and temps nearing 200, of course no one would ever autoclave their bottles though. Having said that, people use the word sterlise a lot, when they actually mean sanitise.

But by the sounds of other peoples experience it appears to be good enough for brew. I might give it a go, Thirsty Boy's trick seems good, do it every time you have accumulated an ovens worth of bottles and store them sanitised.

My current bottle sanitising regime is just a rinse with water after drinking (or within the next day or 2) and on brew day just use some no-rinse sanitiser... Not exactly laborious as I don't use brushes etc.

true - someone quoted the times and temps earlier - IIRC 160 for two hours is pretty standard for dry heat sterilization, this allows enough time for the objects/powders/containers to actually heat up thoroughly and for enough contact time to do the killing - that will sterilize, not just sanitise.

Every 10C you go up in temperature - halves the amount of time required to sterilize... but you still need to allow enough time for things to actually heat up properly. So while 200 will do the killing in 7.5mins ... you need to make sure all the surfaces have actually heated up to that temp... ergo the slow heat up (which also protects the bottles from too much thermal shock) and a goodly excessive amount of time at the high heat.

Trust me... if you take an hour to heat up a foil sealed bottle to 180-200 and leave it at that temperature for 30-60mins, followed by a slow cool down... everything is dead.