Learn to Make Natural Soap

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Soap Scum 101: what is soap scum and how to clean it.

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If you make soap, you need to know what soap scum is. In fact, you’re probably here because you’re wondering what’s up with your shower after you start making handmade soap. Or, your customers are asking about it (if you’re a soap seller).

Soap scum is a real drag… appearing everywhere from the bathroom to the kitchen to the laundry room, creating a never-ending cleaning . But fret not! I’ve got some great tips on how to deal with it, along with an explanation of what exactly it is!

What is Soap Scum?

Soap scum begins as a combination of soap and the minerals present in the water. It also contains whatever else is on the surface (such as body oils, dead skin, etc.) all stuck together in a scummy yuck. The minerals in the water bond with the soap and create a film that appears in kitchens, bathrooms and laundry rooms all over the world. But here’s the big rub: if you don’t remove it, it will attract mold which you’ll notice as it changes color and beginning to smell. 🤢

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Here is a great technical explanation of soap scum:

Hard water and soap produce a curdy precipitate called soap scum. Hard water has a high concentration of dissolved minerals like calcium ions and magnesium ions in the form of dissolved salts. Soap contains sodium salt from stearic acid. In soft water, this sodium dissolves easily, but in hard water, it binds to the minerals and produces insoluble calcium or magnesium stearate, also known as soap scum. Soapless detergents are made from propene and do not produce soap scum. (Biard and Crockett Plumbing and Heating)

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Hard water vs. soft water and soap scum

Soap scum is mostly present in homes with hard water. Hard water contains mineral salts, which contributes to soap scum build up. The number one way to prevent or minimize the soap scum in your house, soften your water with an in-home water softening system. I live in a hard water region, don’t have a water softener, and am still considering if I should get one. The added sodium to the water poses some questions for special health concerns in my family. But aside from that, gosh I wish I had soft water! Ha! We’ll dive in with some cleaning and prevention tips below though.  

A common myth is that using soft water makes it harder to rinse the soap off your skin. If you have soft water and you get out of the shower and feel “slick”, it’s because you are actually clean and those are the natural oils in your skin. Hard water can leave a residue on your skin, which tricks you into thinking you are “squeaky clean”.

Oh, and the whole shower gel thing… Another common solution to soap scum is to switch to liquid bath soap or shower gel in the shower. The reason this works is that liquid soap is NOT SOAP, it is a detergent! This may keep your shower clean but is not the best option for your skin because detergents strip away the skins natural moisturizing system which can cause wrinkles, itchy rashes, or dry skin. Stick with the natural soaps! (As we all will since we are superstars that make our own, wink wink.)

How to Get Rid of Soap Scum

Because we are all about being natural, we will stay away from recommending cleaners that contain chemicals such as ammonia or bleach, which can irritate the nose, stain surfaces, and mar your bath fixtures.

My favorite solution is Baking Soda and Citric Acid. Sprinkle the mixture on and activate it with water or some cleaning solution (I use a real soap cleaner, no detergents here) for a volcano science experiment reaction. I then wipe it around, all the scummy areas, and let it sit and work its magic while I enjoy a glass of wine (ok, I go clean something else most of the time). In about 5 minutes (or 20 if you went the wine route) head back to the skink or shower and give it a quick scrub and rinse. Scum be gone! 🥳

Oh, an important note on this mixture. You can’t premix making soda and citric acid together for storage. Mix when you’re going to use it. Otherwise, you’ll have a brick of the mix. Seriously, rock hard brick that will have you cursing and swearing like a sailor as you try to pry it out of your container.

Next up, you can use Baking Soda and Vinegar – Pour 1 cup of baking soda into a bowl, add ¼ cup of Vinegar to make a paste. Rub it on the surface and let science do it’s magical work. If the soap scum is thick, pour table salt into another container and after dipping the towel into the paste, dab some salt on it and the salt will add a little abrasiveness to the mixture.

Baking Soda and Hydrogen Peroxide can work too – this is for very thick soap scum that builds up in the bathtub. Pour 1 Cup of Baking Soda in a bowl and add ¼ cup of Hydrogen Peroxide to make a paste. Spread it over the soap scum, let it sit for 15-30 minutes and rinse well. Another excuse for a wine break, because, why not?

And my favorite tip of the day is… prevention via vinegar!

When you get out of the shower. Take 10 seconds and spray the shower down with vinegar. Any vinegar will do, but I like to use one that has been infused with herbs or citrus peels (because it smells nice and the citrus has citric acid in it making the vinegar extra powerful). This simple spray down helps prevent soap scum build up, and makes cleaning way easier (dang, less time for wine tasting haha).

You can also use vinegar alone as a cleaning tool against soap scum:

  • I used to just spray vinegar, wait (aka have a glass of wine), then scrub and rinse. Sometimes I still do, but I like the baking soda and citric acid batter in my new hard(er) water home.
  • For chrome and stainless-steel fixtures, vinegar is your best cleaning tool. Just spritz, wait, and rinse. It’s streak free and works great on glass too.
  • For shower curtains, soak in a mixture of vinegar and water (I dunk in a bucket and let it sit while I clean the tub) then rinse.

Soapy Friends vs Soap Scum

Soap scum is here to stay due to it being a natural reaction between soap and water. So, to all of our soapy friends that don’t need soapy scum ruining their fun, keep the baking soda, citric acid, and vinegar handy!

Have any soap scum prevention or removing tips? Drop a comment below (please, please!). And, if you have a favorite wine, you can share that too 🍷

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