I'm not sure that I would add the fatty acid prior to autoclaving. We tend
to autoclave the media first, let it cool, add the detergent, then deliver
the proper amount of fatty acid in ethanol. This seems to work fairly well.
I am curious as to why you use 0.5% fatty acid. Most of the receipes I have
seen call for about 0.1% fatty acid (approximately 4 mM).
Let me know if I can be of further assistance.
dubear at molbio.cbs.umn.edu