DOS Soap – Dealing with Dreaded Orange Spots in Handmade Soap

Have you ever encountered Dreaded Orange Spots (DOS) in your handmade soap? If so, you’re not alone! DOS can be a frustrating issue for those who make soap, but it doesn’t have to be. In this article, we will discuss what Dreaded Orange Spots are, why they appear, how to avoid DOS developing on your soap, and what to do if your soap it gets DOS.

What are Dreaded Orange Spots?

Dreaded orange spots, also known as DOS, are orange spots that appear on handmade soap. They can pop up while curing, or even months later. Usually, they are an indication of rancid oils in your soap but they can develop for multiple reasons. The few times I have experienced DOS on my soap, the culprits were 1: using tap water (hard water minerals); 2: extreme sun and humidity conditions; and 3: old alkanet. Check out the video below for more details on the crazy DOS that developed my first year in Tucson!

Why does DOS happen to handmade soap?

The most common reasons for DOS developing on natural soap are:

• Rancid Oils
• High Superfat
• Tap Water or Other Additives
• Temperature and Humidity

Rancid Oils: The oils and fats we use to make handmade soap all have a shelf life, just like food. The older the oils, the more likely your soap is to develop DOS. When an oil has expired past its shelf life, you’ll know by smell and/or a color change.

High Superfat: The higher the percentage of superfat in your soap (the amount of free-floating or unsaponified oils) the greater the chance for DOS to occur. The free-floating oils can go rancid, or be negatively impacted by additives in your soap.

Tap Water or Other Additives: All of the wonderful things we add to our soaps can also lead to DOS. Tap water is high in mineral content that can cause your superfat to go rancid. Milks have a fat content that can increase the total superfat in your formula, and even some fragrances, botanicals, and other additives can all affect whether or not your soap develops DOS. When I first started using alkanet looking for purple soap, I had a horrible experience… including purchasing old alkanet. Not only did it make gray soap, it got DOS as well. Thankfully, I found AnneGeorges. Anne’s botanicals are always fresh!

Temperature and Humidity: DOS loves to develop on hot sweaty bars of soap. Hot temperatures can cause the superfat to go rancid, and high humidity will allow the natural glycerin in the bars to attract moisture from the air and affect the superfat in the same way. Heat and moisture are not friends to soap!

How do you prevent DOS in handmade soap?

Since we know the common factors that cause DOS, we can easily avoid them!

• Use fresh oils and other ingredients.
• Keep your superfat to a minimum.
• Store your soap in a well-ventilated area.
• Skip the tap water, and use distilled water to dissolve your lye

Fresh is best: As mentioned, rancid oils will cause DOS. So, use the freshest oils that you can. And, this goes the same for most additives. Even some botanicals that I use for coloring can cause DOS if they are a few years old. Be sure your supplier is selling you freshly dried plant material as all organic matter eventually decomposes (and can cause DOS).

If you’re wondering what other additives can cause DOS, the only way to know is from experience. That’s why you should always test new ingredients out on small batches to see how they react. I can tell you that DOS will happen if you use hard tap water or use old (expired) botanicals.

Keep your superfat to a minimum: A superfat between 3-7% (including any fats in the milk) usually provides the all of the benefits of superfat without causing a high risk of DOS. Now, everyone has their own recipe, and preference of superfat. I’m not saying higher than 7% will cause DOS. I’m just saying that if you have a high superfat AND are having issues with DOS, consider it as a possible culprit.

Storage: In addition to your formulation options and ingredients, you can also help your soap avoid DOS by curing and storing it a way that protects it from the elements. Your cure rack should be set up to allow air flow (don’t stash your soap in a plastic bin) and avoid contact with metal. Yup, exposure to metal racks can lead to DOS. That’s another great use for my trusty cafeteria trays.

And, package your soaps! The soaps I discuss in the video below are a case in point. They all developed DOS after excessive heat and humidity exposure. But, identical soaps that were wrapped did not develop DOS. A simple paper wrapper or a cotton bag 100% for sure helps prevent DOS.

Distilled Water: Many soapers say “I use tap water all the time and have never had DOS”. Awesome! They must have some great tap water and pristine plumbing. However, if like your water supply is anything like mine (hard water with older plumbing), your water will probably result in DOS popping up in your soap. So, just skip the tap water and use distilled water. Distilled water has been purified by boiling it off into steam, and allowing just the water (minus the impurities) to settle back into water in a new container.

Is DOS always orange?

While it’s called Dreaded Orange Spots, no. It’s not always orange. The first signs of DOS can be white spots which turn yellow, then orange, and eventually brown. If your soap was colored, the spots might not be clearly “orange”. They could appear as different shades of the colorant or just “off-colored” spots. DOS can even be pink! Here are some single oil color tests that went rancid on me.

Can you use soap if it gets DOS?

Personally, I would not use soap with DOS. It’s rancid oils… YUCK! Let’s not rub that all over our bodies. However, I would use soap with DOS to create laundry soap, by salting it out. Salting out soap is a process that uses salt (go figure) to extract the soap from the other “stuff” typically found in bars of soap: fragrances, superfat (including rancid superfat), colors, glycerin, and even excess lye. You can check out my tutorial on salting out soap for full details on the process (and recipes for my laundry powder, to-go soap crumbles, and floating body soap).

Can you soap with rancid oil?

Most soapers say to never use an expired or rancid oil, and that’s very true for cold process soap. But you can use that oil to make a zero percent super fat and hot process soap. This will fully saponify the oils and the soap can be used for laundry soap, or further salted out and turned into body soap. If you’re in the mood for some advanced soaping, you can formulate a soap with rancid oils for a negative superfat (by adding additional lye), hot process it (so all the rancid oils are saponified), and then add fresh oils after the cook. This will provide you with a decent body bar from formerly rancid yucky oils!

If you’ve experienced DOS, or have other tips for us, please share in a comment below! Learning from friends is the best way to learn and I can’t wait to hear from you.