Ben C said:
I always used to use the microwave. My reasoning is the yoghurt
bacterium is probably weedier than most of the other 99% of known germs
in one's kitchen and you can't expect it to compete in a fair fight. So
I thought if you boil the milk up in the microwave, and then leave it
there to cool down to about 40 degrees _without opening the door_ then
it's in practically a sterile environment since any other bugs in there
have just been microwaved.
Then of course you whip it out, dose it, and shove it into the thermos.
Not sure if microwave radiation actually does destroy airborne bacteria
but you'd think it might, after all they are basically made of water.
You might kill some bugs. If you zapped 1 litre with 5 Mwatts
then most likely you would kill lots of bugs by shaking the crap
out of them. Very high levels have been used to sterilise media.
In a domestic MW oven I don't know.
Anyway, about MW, I did and do use them a bit when I am feeling
cautious. After pouring boiling water into the jar as described
with the milk powder, the temp, of course, drops to the 80's.
Sometimes I then stick the jar with a bit of plastic wrap in the
MV, get a bright torch focussed onto the top of the jar and let
it roll. The water quickly boils and sends the white mass
bubbling up and you must quickly turn off. I do this a few times
and then whip it out, put fresh wrapper on top and leave to cool.
The problem with your using the MW to heat from scratch and then
cool is controlling the boil so it does not go everywhere and
knowing when it gets down to the 40s without contamination.
I do recommend my recent discovery to you (the algorithm at
<
http://tinyurl.com/ywvlg5> with some pictures now), the key
ingredient being the jar in the flask idea. I regard this
discovery as being in the same league in its own way as Kekule's
discovery by way of a dream of the molecular structure of
benzene.