Powdered Oxygen-Based Cleansers – How They Work

Powdered oxygen-based cleanser in bucket with scoopThere are a bunch of oxygen-based cleansers on the market for home brewers. We’re all familiar with products like One-Step, B-Brite, and Craft Meister Oxygen Brewery Wash (OBW), to name just a few. There is also the question among many home brewers whether or not they can use a product like Oxi-Clean to clean their home brewing equipment. The following is my analysis and recommendations.

Note that powdered alkaline cleansers such as Powdered Brewery Wash (PBW) may be confused with oxygen-based cleansers, but they contain no “active oxygen” component. Instead they rely on controlling the alkalinity of the solution and introducing surfactants to break down the oils, soils and gunk. You’ll learn more about surfactants in a bit.

So, what’s the real difference between the varied brands of oxygen-based cleaning products? Generally speaking, not much. I made a few phone calls, spoke at length with two chemists, and gathered the MSDS (Material Safety Data Sheet) for each product examined so I could determine their primary components for comparison.

How Do Oxygen-Based Cleansers Work?
Powdered oxygen-based cleansers work by creating a buffered alkaline solution and introducing an oxidizer, in this case hydrogen peroxide.

The cleaning power of these cleansers is based upon four basic components: builders, oxidizers, sequestrants, buffering agents, and in some cases surfactants may also be used. Other ingredients may be used as well but if they are not considered toxic, or fall below a certain threshold they do not need to be included on the MSDS. Likewise, since these cleaners are not food products they do not need to include an ingredient list on their label.

There may be additional, proprietary components at work which we do not know about and which may serve any number of purposes, so the precise formulation of each of these products is not known but generally they do the bulk of their work in the same way, and it starts with those four or five basic building blocks.

Below is a table showing the breakdown of products, their primary chemical components and the primary role of those components. Some of these may actually have dual roles in solution, which are explained in more detail following the table. A dot in the column indicates that the specified product contains that chemical component. Tap or click the image to open it in a new window.


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The Components and Their Jobs
Builders are responsible for conditioning the water, and acting as pH regulators. They set up the environment in the solution by softening the water and raising the pH so the other components can do their job more effectively. Sodium Carbonate serves as the chief builder in all of the cleaning products examined here, and the formulation is probably very similar with other powdered oxygen-based cleaners on the market.

sodium carbonate powder
Sodium carbonate. Photo: Ondřej Mangl

Sodium carbonate has a dual purpose in oxygen-based cleaning powders. It is used both as a water softener and pH regulator, conditioning and stabilizing the solution so the actual cleaning agents can do their job better. Warmer water helps the solution work better too.

As a water softener sodium carbonate works by literally swapping ions with magnesium, calcium and other metals that contribute to hard water. As a pH regulator it helps to raise the pH, making the solution less acidic. Grime left behind by the brewing process is on the acidic side, so increasing the alkalinity of the solution helps neutralize acids and facilitates the efficient removal of the dirt by oxidizers or surfactants.

Surfactants and Oxidizers are responsible for the cleaning action in a solution. When dissolved sodium Percarbonate — the Oxidizer responsible for the “oxi” or “active oxygen” used in the labeling of some oxygen-based cleansers — yields two things: hydrogen peroxide and sodium carbonate.

The sodium carbonate released is relatively ineffective, and is used mainly as a carrier to get the hydrogen peroxide into the mix. At some level it may assist with stabilizing the solution, or may act as a mild surfactant to help break down oils, but the real work is done by hydrogen peroxide.

Hydrogen peroxide molecule
Hydrogen peroxide molecule,
the “OXI” or “Active Oxygen”

As an oxidizer hydrogen peroxide literally pulls electrons away from molecules in the compounds that form the gunk and soil to be removed. The soil is thereby chemically altered and its properties changed, leading to its break down and removal.

Some active oxygen cleansers may include surfactants too. As we know, oil and water do not mix, but surfactants have a hydrophobic (or lipophilic in this case, “oil loving”) end which connects to oils, and a hydrophilic end which connects to water, so they allow oil and water to “mix” thereby conveying the oily soils through the solution, to be rinsed away. Ethoxylated alcohol is used as a surfactant in Oxi-Clean to remove soils, and can cause a foaming action which I have noticed exclusively with Oxi-Clean while sampling these products.

Sequestrants (Chelating Agents). While builders soften water by altering the chemistry of metals in the solution, sequestrants actually surround metal ions and prevent them from interfering with other processes at work in the cleaning solution, or building up on surfaces.

Sodium polycarboxylate, aside from sounding funny and being a mouthful to say, is used in Oxi-Clean as a sequestrant, or chelating agent. As mentioned earlier, what these do is surround metal ions, rendering them ineffective in the solution. Sequestrants work with the builders to control metals in hard water. Sequestrants are also effective scale inhibitors, minimizing the build-up of compounds such as calcium carbonate. Craft Meister Oxygen Brewery Wash (OBW) employs sodium hexametaphosphate in the same capacity, but it also may serve a dual purpose as a dispersing agent which helps to break down various soils.†

Buffering Agents help to maintain the pH balance of the solution. While builders set up the water initially, bringing up the pH and removing metals, the buffering agents are there to counter the effects of acidic soils as they break down. These buffering agents help control the pH throughout the cleaning process.

Additional components used in these cleansers may have a single or dual purpose. We see sodium metasilicate in Oxi-Clean and OBW, as well as sodium silicate and sodium salt, which combine to form sodium metasilicate in B-Brite powdered cleanser. These are likely used in general as buffering agents, but may also serve a secondary function as flocculants, which clump soils into larger particles causing them to drop out of solution. Because of that they tend to prevent redistribution of soils on to areas that have been cleaned.

Sodium Chloride (your basic table salt) and sodium citrate are present in One-Step oxygen cleanser and, according to one chemist I consulted, whose field is detergents and cleansers, sodium chloride is very versatile and could be used as a conditioning or conductivity agent. Through my research I learned that sodium chloride and sodium citrate combined are used as a buffering agent, and that may be the case here. Sodium citrate can also act as a mild chelating agent.‡

Summary
To sum it up, most oxygen-based cleansers consist of generally the same chemical components, and do the job in much the same way. They may irritate the skin, eyes, and can cause ill effects if inhaled or ingested. Wear rubber gloves to be safe, and eye protection of you feel the need.

Play it safe, don’t splash the stuff around, don’t inhale the powder and don’t eat or drink it! Even though they are relatively safe, and eco-friendly, these are chemical cleansers so use them carefully and cautiously.

Now that we’ve examined the chemical components of these cleansers, let’s answer the other question: Can we use Oxi-Clean to clean our brewing equipment? Yes! But I suggest you use Oxi-Clean FREE It contains no perfumes or dyes. Chemically speaking, Oxi-Clean is basically the same as the others, with the added effects of ethoxylated alcohol. Used as a cleanser to remove tough beer stone, yeast gook, glop, slop and other funk from the inside of your carboy, fermenting bucket or brew kettle, it performs just as well as the others. I speak from personal experience.

As I mentioned earlier, this is a non-biased examination, so I will continue by stating that each of the products mentioned herein perform as advertised and do the job very well, as I’m sure other oxygen-based powdered cleansers do.

Personally I recommend rinsing when using any of these cleansers. I tend to use them to clean my brew pot, carboy or bucket fermenter, and other equipment after use, or for cleaning and de-labeling my bottles before sanitizing. I use iodophor to sanitize my equipment, but there are many fine sanitizers on the market for home brewers.

Notes:
The instructions on products like B-Brite, Oxygen Brewery Wash, and Oxi-Clean Free recommend rinsing after use. The reason for rinsing is that a residue of calcium carbonate is left behind by the cleaning process.

According to the manufacturer’s website One Step is labeled a no-rinse cleanser because “If One Step is used on a surface which is clean to the naked eye, rinsing is optional. Residues of One Step are non-hazardous when small amounts come into contact with wort [or] must.”

Regarding product strength, their site also states “To remove heavier greases or waxes, a strong product may be necessary, typically one with a much higher degree of alkalinity…” So One Step may actually be slightly less potent, and less aggressive than cleansers which do recommend rinsing.

This article is not intended to confirm or deny the need for rinsing after using these products. Follow the labels and use your judgment. Likewise, this article will not support or deny claims of a product’s potential to sanitize. Some ingredients used in these products may indeed have disinfectant qualities, but they are called cleansers, not sanitizers.

Avoid Oxi-Based Colon Cleansers!
As a dopey side note, while doing my research I stumbled upon an “oxygen-based colon cleanser.” I kid you not. I advise that you refrain from consuming any oxygen-based product, except maybe air, and I also urge you to stay away from any “colon cleansing” product in general. They might not kill you, but it can give you one hell of a case of gas, and could make you sick. What’s worse? They don’t really do anything except empty your wallet.

While it may facilitate the rapid evacuation of product from your colon, it won’t clean your colon. Your colon doesn’t need any help, if you’re healthy there are plenty of fun-loving bacteria in there that do the job for you, leave them alone! If you don’t feel good and your poop looks funny, double check your diet and see your doctor. All colon cleansing products are a damn rip-off!

There, that’s my public service announcement. On that note, happy brewing, happy evacuating, and happy oxi-cleansing! 🙂


References:
Dawn Chemical, Inc. Presents The Chemistry of Cleaning
Sodium metasilicate – is it a cleaning agent?
Sodium metasilicate ph alkaline

Wikipedia:
Sodium hexametaphosphate
Citrate
Hydrogen peroxide
Sodium Carbonate
Sodium Percarbonate
Sodium Silicate
Sodium Acetate
Ethoxylation