Don't Fear the Foam August 08 2014
When it comes to making beer and wine, it's sanitation first! When it comes to keeping things sanitized, we love the Star San. This foaming, acid-based sanitizer foams up to get into every nook and cranny you need to keep free of potential harm to your brew. However, DON'T FEAR THE FOAM! Star San is no-rinse sanitizer for good reason; the foam breaks down into very simple nutrients that can be beneficial for your yeast.
Star-San will “last forever” if RO or distilled water is used to mix it and it stays enclosed like in a spray bottle or in a covered plastic bucket. It lasts a long time anyway and can be used multiple times or up to about 3 months. If it starts to turn cloudy, it's time to dump it and make a new batch.