Pressure cooker or autoclave total dissolved solids meter

[estelle]

Hi,
I am wondering what other labbies use, pressure cooker or proper autoclave for making agar and for sterilising the agar plates.
Southen biological sell a 9 Ltr one for almost $600 but I am curious to know if I can just buy a pressure cooker from an electrical shop that will serve the same purpose.
My HT has just said that we have some $$$ left in the budget to be used by next week.

The other item requested is a total dissolved solids meter which I think is going to be out of our price range. So maybe we will just go for the test tablets. Does anyone use a meter and do you think it is worth the money, we would only use it a couple of times per year
Thanks
Estelle

[Rita]

Hi
I use a pressure cooker. Had no troubles yet.
Rita

[Loopy]

Hi Estelle,
I use a pressure cooker and have no complaints what-so-ever. I use the tape that changes colour to show that sterilisation temperasture has been reached and oven bags, and really find it quite easy. Before I had this job I had a morbid fear of pressure coookers but now have no qualms using one.
Lou.

[Labbie]

We use the microwave, and its just great. I do not like pressure cookers at all.

[kimmy]

I use to use a pressure cooker all the time untill I read the way to do it in the microwave here on chemtalk now i always use the microwave so much easier and soo soooo much safer and no complaints as of yet.

KIMMY

[SGG]

Hi Estelle
I had to buy a new pressure cooker when I started here and found a 9L one in a kitchen/ chef specialty shop for $150. I use it sterilizing the agar originally and for destroying the agar plates after use. I personally don't think a microwave is very good for destroying agar plates as the power can vary with age and "cooking" with the amount of moisture in the agar. I have seen cockroaches running around alive in a microwave while it is being used! The pressure cooker is good because it keeps at a constant pressure for the specified length of time. These new pressure cookers are nothing like the old ones and are very safe.
Regards
Sue G

[J]

I always use the microwave for making agar and destroying the plates. I can guarantee there would be no live cockroaches running around in the oven bag in the microwave when it gets hot enough to totally destroy the petri dishes. Any cockroaches or anything else that decided to run around in there would be well and truly boiled to death. Just as they would be in the pressure cooker.
Give me the microwave any day. Much less fussing around, and always successful.

Julie

[Sassi]

A pressure cooker is great...

BUT dont do what I did one particularly busy afternoon... I went to sterilize some very foul looking plates, the teacher had insisted on keeping them in the incubator for wks and I have never seen anything quite like them, they stunk and I could almost feel all the bacteria and fungi creep up my hands and spreading all over my body... so I threw them into the pressure cooker and turned it on and dashed out of the room to wash my hands and get some fresh air... I left it for the required time, when I returned to the room I was met by the worst odor you can ever imagine, death doesnt even come close... I immediately realized my misstake, they were PLASTIC plates, and in my rush I forgot to put it in the ovenbag!!! The stuff was all over the pressure cooker, It took my nearly 2hrs to clean up the mess, 2hrs of constant gagging and nearly passing out from the foulness... trust me, I will never make that misstake again!!! After that I had to taketwo days of sick, whether I was actually sick or it was just mentally, thinking of all the germs that I must have come in contact with, I still dont know...

[estelle]

Thanks for all the replies I think I will investigate the pressure cooker idea to start with.
Estelle

[sunray18]

We used to use a pressure cooker.. the a teacher brought in an old microwave ..
I would never go back to pressure cookers now...

[estelle]

I was thinking about the experience with the melted agar plates and the time you had to have off, I don't think it was all in your head by any means.
I had a live blood analysis during the holidays and the naturopath that was checking the results asked if I was a smoker because something seems to be attacking my immune system and my liver isn't functioning as well as it should. I don't smoke and I use enjo products to clean around my home and I use a laundry ball for washing, I can't even wear perfumes because they make me sick. I mentioned that I work in a science lab and the last week of term I spent in the chemical storeroom doing a stocktake and clean up of all the bottle lids and shelves of some disgusting black greasy mould. I worked for an hour or two then had to come out because I felt sick and had a slight headache. Her reaction was a big AHA!! She said I should wear a respirator as well as the gloves and lab coat I have, she also suggested that I look for another job. I like my day job, I just don't like all the chemical fumes I cop sometimes. She said I am definately not doing my health any favours, no wonder some of the other labbies say we need danger money, who knows what long term damage we might be doing. We can all show evidence of cuts, burns etc but when it comes to internal stuff that is another story.
Actually this job is an exact opposite from my other job which is a relaxation, pregnancy and infant massage therapist and I also make natural (or as much as possible) body products. It keeps me sane.
So I hope you didn't suffer any long term effects from the agar soup you accidently made.
Cheers, have a great weekend.
Estelle

[lada]

Estelle,
i use pressure cooker with the gauge to tell me the pressure. Have no problems.
We also use TDS meter, only because we do streamwatch duties and the kit comes with meter. It is very accurate and easy to use. Not sure of the price.
Lada

[Ocker]

Hey Estelle investigate an exhaust fan in store room, cheap easy fix!

[Labbie]

Last time we got onto this subject, some one suggested while sterlizing in a Microwave for agar, put some __________________ tape that changes colour, to tell if it is sterlizied ok. Auto _____ tape, can any one tell me if this is correct??

[The Search Engine]

Hello my labby brains trust - slightly off topic but could I ask ...
How do you prepare agar plates in the microwave? I'm wandering around the boards and haven't found it yet.
Thanks.
Search

[The Search Engine]

Hi folks, I may need to retract that last request, as I have found some threads on making plates.
Cheers,

[Loopy]

Hi Sue,
It's Autoclave tape.
It has stripes on it that turn black when the item reaches the proper sterilisation point.
Lou.

[sunray18]

To make agar plates using a microwave, I put the ingredients into a glas Schott bottle, and microwave on full power for 8-10 mins... then pour into sterile petri dishes as usual..
To 'kill' used plates.. I put the plates into 2 oven bags, sealed separately, then microwave on high for 8-10 mins..
It is so much fun as the plates pop and carry on and they all melt and go wierd shapes....

[Labbie]

Does any one use autoclave tape in their microwave????????? Perhaps the tape we have here is too old????????

[Cuishie]

I was just having a discussion with my teachers regarding why the oven bags don't explode when you seal them and heat them in a microwave. None of us could really work it out. There is probably a really simple explanation, does anyone out there in labbieland know why they don't?