I'm no gent but I'll offer up an answer. Bringing water to a rolling boil ie 100 deg c is sufficient to inactivate pathogenic and spoilage organisms. To be clear this isn't sterilisation which is more difficult. For practical purposes because a mesh bag has very little heat capacity you can assume the temperature reflects water temperature. Personally my approach is to boil water in a kettle, stick whatever I'm looking to sanitise in a pyrex jug with the water and microwave it for a minute or two till it boils. This works for sugar solution for bottle priming as well.
I used to boil mine to death and had no problems doing that. Solvents also work...but some melt some materials..some just dunk in starsan...or radiation...