I have prepared MHB and need to supplement it with 1% of different carbon sources (glucose, sucrose and starch). Which one is better, filter sterilized or autoclave these carbon sources? I've read that carbon source can be autoclave separately and some said better to filter sterilized them.. I've prepared 20% stock solution for each carbon source except for starch. can anyone describe how to prepare starch stock solution (i'm using soluble starch)?