Oatmeal Soap Recipe (Cold Process)

Oats are a soothing skincare ingredient perfect in soap recipes for sensitive and inflamed skin. There are different ways to add them, so I’d like to show you a couple of techniques in this all-natural oatmeal soap recipe. It’s from scratch using the cold process method and includes a touch of honey added at the right time to create a creamy color and boost the lather. This piece includes info on using rolled oats, quick oats, oat milk, and colloidal oats in soap making.

Oatmeal is an excellent soap additive that is not only easy to source and inexpensive but also has incredible skin benefits. I remember getting a terrible sunburn many years ago—it was one of those early spring days that I spent working all day in the garden. Nothing could soothe the pain and inflammation except for a warm bath made with oatmeal.

A cup of it in the water was enough to relieve the pain and help me relax. That’s because oatmeal contains several compounds proven to reduce inflammation. The main one is called Avenanthramides, which reduces the skin’s production of cytokines. These are proteins secreted by the immune system to affect other cells. In the case of inflammation, to tell cells to be inflamed and sore. Oatmeal also contains lipids and polysaccharides (starch) that restore your skin’s moisture balance.

All of this makes oatmeal a humble but mighty skincare ingredient. You can use it in lotions, skin cream recipes, facial scrubs, bath fizzies, and even handmade soap. Although soap is a wash-off product and spends less time on your skin than other products, oatmeal can still make it gentle and creamy.

Ways to Use Oatmeal in Soap

Getting those creamy skin-loving oats into your soap is easy, and there are a few ways to go about it. The simplest way is to sprinkle them on the tops of your bars as a decoration. They may add light exfoliation this way, but it’s more about presentation. Another way is to stir oats into soap at emulsion or trace. All sizes of oats can go in this way, but finely ground colloidal oatmeal is the least noticeable. Larger oat pieces can act as light exfoliation when added this way, and can also look interesting in bars cut from loaves.

I used to make a lavender soap with oatmeal to sell using this method some years ago. I swear that it held its fragrance much better than standard lavender soap bars! Perhaps the essential oil is partially absorbed by the oatmeal, which then slowly releases it over time. Lastly, you can blend oat milk or an oaty water into soap recipes. This provides all the benefits of oats without requiring physical pieces of oatmeal.

Oat Milk in Soap Recipes

Milk, such as goat milk, has long been used in natural soap recipes for its creamy feeling and benefits for sensitive skin. Not everyone can use dairy milk in soap, though, for reasons ranging from ethical preference to allergies. In that case, we can get some of the same benefits of dairy milk soap from vegan alternatives such as coconut milk and oat milk.

Adding oat milk to soap recipes is much like adding dairy milk – you use it in place of some or all of the water called for in the recipe. Just as with dairy milk, you have to be careful not to scorch it when it comes into contact with the lye. For this reason, there are two methods to add oat milk to soap recipes. For a full water replacement, freeze oat milk and stir the frozen cubes with the lye crystals. When you mix the frozen oat milk with the lye, it melts, but the temperature doesn’t get very high.

The easier way to add oat milk to soap recipes is with a partial replacement. Lye needs at least its own weight in water to dissolve and make a lye solution. So you use only that much water, and replace the rest of the water called for in the recipe with oat milk. You add the oat milk by pouring it into the warm oils before adding the cooled lye solution.

Oatmeal, Rolled Oats, and Colloidal Oats

There are quite a few different oat products out there, and it can be confusing choosing one for soapmaking. The good news is that, as long as the product is 100% oats, you can use it! When oats are harvested and processed, they’re rolled, cut, and ground into different grades.

Old-fashioned rolled oats are the largest flakes and are my favorite type for using as oaty soap decorations. Mixed into the soap batter, they can also work as a gentle skin exfoliant. Quick oats are a bit finer and cook down to a porridge consistency. They, along with oat flour and colloidal oatmeal, will make your lye solution gloopier than rolled oats. That’s perfectly fine, though, and is just more of the starch in the water. Make sure to scrape all of it out of the jug when adding to the oils.

Both oat flour and colloidal oatmeal are fine grades of oatmeal that you can barely feel in soap. Both add the same goodness as larger pieces of oatmeal, but without the abrasion. They might even be better to use since they have a larger surface area, which means more opportunity for extraction. You can make oat flour at home by putting oatmeal in a coffee grinder and pulsing it until it’s a fine powder. Colloidal oatmeal isn’t easy to make at home since it’s ground and then sifted through extremely fine screens.

Gluten-free Oatmeal Soap

If you have a celiac in the family or want to ensure your products are safe for customers with celiac disease, consider using gluten-free oatmeal. Oats are naturally gluten-free, but are often processed in places that can have gluten contamination. Though gluten needs to be digested to have a celiac effect, it’s better to be safe than sorry! Gluten-free oats are becoming easier to find in supermarkets, but if you’ve not seen them, you can purchase them online.

Troubleshooting Oatmeal Soap

Feel free to use one or several of the methods described above when making oatmeal soap. However, be aware of a few things. First, too much oaty material in the bars may feel too scratchy for some people. I recommend using up to one Tablespoon of oats per 454 g (1lb) batch of soap. You can use more, but that might affect how the soap lathers and feels on your skin.

Additionally, soap made with oat milk can heat up after being poured into the soap mold. If you’d like to avoid partial gels, consider taking steps to prevent the soap from overheating. That may mean refrigerating it or using cavity or slab molds, rather than loaf molds. I’d do this anyway if you want to have lighter colored bars. Personally, I like a bar of oatmeal soap to have a lovely oaty color, which is why I use honey in the recipe below.

Making the lye solution with oat milk, oaty water, or oats may cause it to thicken. It could be ever so slight or full-on goop. If this happens to you, don’t worry, it’s perfectly normal. Don’t strain the lye solution through a sieve if that was your plan; instead, scrape all of it into the oils. A whizz and blitz with the immersion blender, and it will be like the thickening never happened.

Lastly, using oat milk or an oaty infusion in soap may give you blue bars! This only seems to happen when using loaf molds, and the light blue color fades rather quickly. It can be alarming to see at first, though. Soap-making can be full of surprises!

Sensitive Skin Soap Recipes

• Goat’s Milk Soap Recipe
• Simple Tallow Soap Recipe
• Honey and Beeswax Soap Recipe
• Shea Butter Face Soap Recipe