More and more I find myself in the need of a little Starsan to sanitize equipment in between brews. To sanitize a pipet to do a gravity read, to sanitize raking equipment, etc.
I’ve been thinking about making a decent amount and then storing it in 1 Gal water jars. Does anyone know how long it will stay “good” or keep it’s sanitizing power? Is making a batch and then storing it a good approach or should I figure out a way to make small amounts “fresh” every time? The way I’ve been making it at brew day is to add an amount to 2 gal in a brew bucket and that works great but I’d love to hear how you do it.
If you mix it up with RO water, it will last a long time. You can check the pH to determine if it’s still good. I think as long as it’s below 3, you’re fine. A lot of us keep a spray bottle of StarSan handy for the small tasks you’re describing. I typically mix up 5 gallons at a time, 2-3 times per year depending on how often I’m brewing.
Another thing you can do to “save” star san" is to mix less. Instead of mixing 1oz in 5 gals try mixing .5 oz in 2.5gals. Then try to put it in a container that will be air tight like a fermenting bucket. As long as it stays below 3ph it is fine.
I tend to keep it for a couple months tops to be safe. I just will run off two to three gallons from a five gallon mix and keep them for incidentals and spray bottle use. I’ll also use those for the random batch here and there. For the price overall I just find it easier to use fresh stuff for the bottling process. I will use the two to three gallons of saved from the previous batch for the initial bucket/carboy cleaning and whatever other items I need to clean. Just my process.
I usually mix up a new 5gal batch on bottling day and fill up a spray bottle and store the rest in a carboy. I brew about once a month so I would say I mix up a new batch around that often. I bought some cheap pH strips to make sure it’s still below 3 but with these strips the color could be anywhere from 2-4 which kinda defeats the purpose. I figure a month or so is long enough to keep it around without having to worry.