Paul Stewart stewart at bud.peinet.pe.ca
Sat Feb 18 12:18:45 EST 1995

To the person attempting microwave media sterilization:

I asked for info on this on this newsgroup a couple of months ago, and 
got a wide range of replies; everything from, "forget it, it won't work"
to, "our lab has never had contamination in years wih our microwaved 
instruments".  The general consensus seems to be that it is chancy at 
best. I have had good luck with liquid media by nuking for 30 minutes on 
High.  You need to have lots of headroom in the bottle, since it will 
boil over otherwise. I put a couple of coffee mugs full of water and that 
reduces the loss of water from the media. You will still lose about 
10-20%, so make the media up with extra water to allow for this. 
	My guess is you should presoak the grain, straw or woodchips, and 
include a fair amount of water when you nuke it. I had to nuke only three 
bottles of straw/grain at a time for about an hour. No contamination yet, 
but I feel microwave works best on small volumes of liquid, where 
hot/cold spots matter less due to mixing.
	Maybe your inquiry will spark discussion on this. I feel the 
topic is far from having reached a consensus. Wadda ya say experts?
......Paul from the Great White Northeast.

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