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As you probably know, anything that touches your wort or beer after the wort has been boiled must be sanitized. So naturally, one of the things you’ll find yourself doing all the time as a homebrewer is sanitizing something to keep your wort/beer from getting infected. The easiest and most economical way I’ve found to do that is to keep a spray bottle of sanitizer around for just such an occasion. Whether you’re spraying your brewing spoon before using it to displace the heat in your wort while it chills or you’re spraying your thermometer before checking the temperature of your rehydrating dry yeast, you will always need sanitizer handy and making a full batch of sanitizer is often unnecessary, wasteful, and expensive.
As you might imagine, making a spray bottle of sanitizer is an easy task. Let’s look at what you’ll need.
Items Needed
- Spray bottle (Pro-Safe Bottle 3-pack)
- Sanitizer (Star San)
- Measuring spoons (1/8 tsp and/or 1/4 tsp) (OXO Good Grips Measuring Spoons)
- Water
Choosing a Spray Bottle
Since it’s the item above that serves as the core piece of equipment, I highly recommend that your spray bottle meet a few criteria.
- Buy a new bottle – You can reuse a bottle you currently have if and only if, it’s only been used for plain water in the past. If you don’t have a spray bottle with water in it that you want to re-purpose, buy a new one. You don’t want to mix chemicals (sanitizer and whatever used to be in that bottle) nor do you want to spray whatever residual chemicals are in there now onto your brewing gear. These bottles are cheap – buy a new one.
- Buy a sturdy bottle – This bottle will get used frequently. It will get dropped and banged up. Splurge the extra buck or two for one that’s really well made.
- Buy a bottle with an adjustable spray valve – You will almost always use your sanitizer spray bottle in a misting or fan mode. Having the ability to adjust the size of that mist/fan will come in handy depending on what you’re sanitizing. If you’re sanitizing something large, a broad spray is helpful. If you’re sanitizing the inside neck of a flask or something else that’s narrow (like if you were making a yeast starter), a big spray is just messy.
- Buy a bottle of a manageable size – If you have a bottle that’s under 16 ounces, you’ll be making sanitizer solution all the time. If your sanitizer spray bottle is over 32 ounces, it’ll likely be unwieldy and tough to use in smaller spaces. I love my 24 oz bottle and think it’s the perfect size.
- Buy a bottle that has volume measurements (optional) – I find that having volume measurements on anything volume-based that I use in the brewery (jars, bottles, kettles, etc.) is beneficial.
- Buy a bottle that’s transparent or translucent (optional) – It’s helpful to see if you’re running low on sanitizer before you take that sanitizer off to use on a project.
Do you have your spray bottle? Let’s make some sanitizer solution.
Making Sanitizer Solution
To keep this tip simple, I’m going to assume you’re using Five Star’s Star San. While you can use an iodine-based sanitizer (Io Star Sanitizer as an example), a bleach based sanitizer (not recommended), or even cheap undiluted vodka/grain alcohol (expensive), Star San is far and away the most popular sanitizer.
So how do you make your sanitizer? First, you need to confirm the size (i.e. volume) of your spray bottle. My bottle is holds 24 oz at its fill line. Oftentimes, the volume is stamped into the bottom of the bottle. If not, you can always use a measuring cup and add four ounces at a time until it’s “full.” I put full in quotes because you need to leave a reasonable amount of head space. You’ll need space for the sanitizer you’ll add and you’ll need space to allow the solution to blend well when you shake it to mix. If it’s full to the brim, it won’t mix well.
With your empty bottle in hand and its volume in mind, add the amount of sanitizer below that matches the volume of your bottle.
NOTE: The underlying ratio is 0.01 tsp of Star San per ounce of water.
- 1/8 tsp for 12 oz or smaller bottle
- 1/4 tsp for 16-24 oz bottle
- 1/4 + 1/8 tsp for 32 oz bottle
Once you’ve added your sanitizer, fill your bottle with water to its fill line or leaving head space. Because Star San is thick and will cling to your measuring spoon and because these are such small amounts, I’d suggest you dip your measuring spoon into the water-filled bottle and swish it around to get off as much sanitizer as possible. Don’t go haywire and spill your solution everywhere but give the spoon a quick rinse swish.
TIP: Using a permanent marker, write the amount of sanitizer you need (e.g. 1/4) on the bottom of your bottle. It’ll always be handy when you’re refilling in case you draw a blank on how much sanitizer to use.
Put the sprayer head back on your bottle and give it a good hearty shake to mix. It should foam up into the empty head space – that’s a good sign. Now go sanitize something!
Now that you’ve read this Homebrew Tip, let me know if you have a question, recommended improvement, or other thoughts in the comments below. As I mention in About Homebrew Notes, these are living documents and your feedback is appreciated!