Mindtaker

I just want to add my $0.02 in. It can take quite a bit of heat at normal atmospheric pressure to kill normal household bacteria. The best way to kill bacteria with heat at home is probably a pressure cooker. I'm uncertain at a specific response to cold temps. since some bacteria will just go dormant and not actually die. Many bacteria can survive a high salt content enviroment. That would really depend on the specific bacteria. However, in general most bacteria will probably have to struggle to surive on a 100% salty enviroment. Althought the biggest problem would be that the bacteria need water. To test this you'll want to soak the spoon overnight in a salty, aqueous place.

As far as I know no thermophiles are pathogenic to humans. I would guess that is probably because of the evolutionary circumstances that humans lived in versus the thermophiles. Just think of how many humans have survived by swimming in very hot (and sometimes acidic) places, like Yellowstone's geysers.

You definately have fungus on your plate. Althought it's hard to tell what exact type of fungus it is I'm not an expert. I'm assuming those are blood agar plates? Follow the steps below in order to get better results for bacterial growth. It sounds as if your plate preparation needs work. Once you make the agar you will want to autoclave it (or sterilize it somehow, pressure cooking is a good option if you don't have an autoclave). Once the agar is autoclaved you will want to wait until it is cool enough to touch, it is better to let it cool in a water bath (usually mine are around 55 degrees C). Then if you can light a continuous flame (like a bunsen burner) by the agar and the sterile petri dishes. Then just pour the plates by the flame. Then let them cool until they are hard (or at least not fluid-like) but don't put them in the freezer (I'm not sure why, but my professors have always told me not too). Just remember that nothing is sterile around you except the sterile petri dishes and the autoclaved agar (not even the air which is probably where your fungus came from). Sorry this is so long.