What Is Sodium Percarbonate? A Home Brewer's Guide to Cleaning & Sanitising
Quick answer: Sodium percarbonate is a white powder made of sodium carbonate (soda ash) and hydrogen peroxide. Dissolved in warm water, it releases oxygen that lifts dried-on yeast, protein and stains, without chlorine or scrubbing. Home brewers use it to soak fermenters, bottles and kegs. Clean first, then sanitise anything that will touch your beer or wine with ChemSan just before you use it.
If you've ever bought an "oxygen" or "oxy" cleaner, you've probably used sodium percarbonate. It's the active ingredient in many brewing cleaners, and it's one of the most useful powders a home brewer can own. Here's what it is, how it works and how to use it safely.
What is sodium percarbonate?
It's a solid form of hydrogen peroxide. The peroxide is locked into crystals of sodium carbonate, so it's stable as a powder. Add water and it splits back into its two parts:
- Hydrogen peroxide releases oxygen, which breaks down organic soils and stains. It then decomposes into water and oxygen.
- Sodium carbonate makes the water alkaline, which helps loosen grease, protein and the "krausen ring" left by fermentation.
Because it breaks down into water, oxygen and soda ash, it doesn't leave the chlorine taste that bleach-based cleaners can cause.
Cleaning vs sanitising: why it matters
These are two separate jobs, and you need both. Cleaning removes the dirt you can see. Sanitising kills the microbes you can't see. A sanitiser can't work properly through a layer of grime, so always clean first. Our guide to cleaning vs sanitising explains the difference in detail.
Sodium percarbonate is above all a cleaner. For the final step just before brewing, we recommend ChemSan, a no-rinse sanitiser used at 2 ml per litre for at least 2 minutes.
Our sodium percarbonate products
| BrewCo Sodium Percarbonate | Chemclean | |
|---|---|---|
| What it is | Sodium percarbonate | Strong alkaline cleaner with sodium percarbonate and sodium metasilicate (a PBW alternative) |
| Best for | Routine soaks for buckets, bottles and kit | Heavy soiling: baked-on protein, stains, kegs and tanks |
| Dose | 5 g per litre (115 g for a 23-litre fermenter) | Scrubbing: 50 g per 5 litres. Soaking or circulating: 50 g per 20 litres |
| Contact time | About 10 minutes | 30 minutes circulating at up to 60°C, or a 4-hour soak |
| Rinse? | No rinse needed, according to the label | Yes, always rinse thoroughly |
| Make up | Fresh, and use within 1 hour | Fresh, just before use |
Our own sodium percarbonate is also available in a 500 g tub.
How to use sodium percarbonate
- Rinse off loose debris with water straight after use, before it dries on.
- Dissolve the powder in warm water. It dissolves and works faster warm than cold. Follow the dose on the product you're using.
- Fill or soak. Fill the fermenter to the top, or submerge bottles, so the solution reaches every surface. For stubborn rings, leave it longer.
- Wipe with a soft cloth if needed. On plastic, avoid anything abrasive, because scratches can harbour bacteria.
- Drain, and rinse if the product says so.
- Sanitise with ChemSan just before the equipment touches your brew.
A soak in sodium percarbonate is also the easiest way to get labels off bottles you're reusing. They usually slide off after an hour or so in warm solution.
Safety
- Wear gloves and eye protection. It's alkaline and can irritate skin and eyes. Chemclean is stronger and can cause burns.
- Never seal a container of made-up solution. It gives off oxygen, and pressure can build up.
- Don't mix it with other chemicals, especially acids. If you're following it with an acid sanitiser like ChemSan, rinse the cleaner away first.
- Take care with metals and coatings. Alkaline cleaners can dull aluminium, and Chemclean isn't for Teflon-coated surfaces. Stainless steel, glass and food-grade plastics are fine.
- Store the tub sealed and dry, away from heat and anything combustible.
How it compares with other cleaners
| Product | What it does | Dose | Rinse? |
|---|---|---|---|
| Sodium percarbonate | Oxygen cleaner for soaking kit | 5 g per litre | No, according to the label |
| VWP | Cleaner and steriliser in one step | 1 tsp per gallon (4.5 L), 10 minutes | Yes, thoroughly |
| ChemSan | No-rinse sanitiser for clean equipment | 2 ml per litre, 2+ minutes | No |
| Pipeline Purple | Beer line cleaner for taps and dispense lines | 100 g sachet in 10 litres | Yes, flush with clean water |
For taps and beer lines, use a dedicated line cleaner. Our guide to cleaning beer lines at home shows you how.
Can I use supermarket oxygen cleaner?
Many household "oxy" products contain fragrances, detergents or brighteners as well as sodium percarbonate. These can leave scents or residues that taint beer and wine. Buy a brewing-grade product so you know exactly what's in it.
Browse our full range of cleaning and sanitising supplies, or see our comparison of the best sanitisers for home brewing.