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My Reward PointsA marbled loaf of smelly and creamy homemade soap is ready to be cut. However, after a day or two, a white spot on soap appears. This strange phenomenon concerns both soap manufacturers and consumers. Understanding the cause, remedy, and future prevention is crucial.
What Are White Spots on Soap?
Natural white spots Soap bars are often caused by soda ash production, a white, powdery residue that forms during the curing process. These spots are cosmetic and do not affect soap safety.
Are White Spots on Soap Harmful?
White spots on handmade soap are cosmetic issues, but not hazardous. They are caused by soda ash and are safe if they lather normally, have no rancid smell, and have no unusual textures.
Common Causes of White Spots on Soap
White spots on soap are caused by soda ash, along with excessive glycerin, lye, or fragrance and additives, and can also result from overuse of hard oils and fats.
1. Soda Ash
White patches on soap are formed when soap cools too quickly that results in a white, powdery coating on the soap's surface known as soda ash.
2. Overuse of Hard Oils and Fats
White spots, also known as "stearic spots" in soaps, are caused by incorrect hard oil and fat ratios or their overuse and low soapmaking temperature, affecting the soap's quality.
3. The Presence of Lye
White spots on soap can be caused by lye, which is often caused by innocuous soda ash, but incorrectly mixed lye pockets can be dangerous.
4. Excessive Glycerin
Addition of glycerin in excessive quantity during saponification can cause uneven moisture attraction, resulting in white crystalline patches or pockets of glycerin on the soap's surface during cooling and curing.
5. Soap Curing and Drying Issues
White spots are tiny, white crystalline patches of stearic acid from unreacted oils, formed when air reacts with unreacted lye, and can result from soap curing and drying issues.
6. Fragrance and Additives
You can encounter white spots on handmade soap, which are the result of fragrance and additives. The other common culprits are air bubbles and soda ash from hard oils and butters.
How to Prevent White Spots on Soap?
White spots on soap can be prevented by maintaining proper temperatures and proper curing conditions, choosing the right oils, avoiding excessive lye, and using balanced additives in your recipe.
1. Proper Curing Conditions
White spots on soap can be prevented with proper curing conditions, but soda ash is a distinct issue that can be resolved during the curing process.
2. Avoiding Excessive Lye
White spots on soap can be caused by temperature, lye excess, or low temperatures. In order to avoid lye-heavy bars and unmelted stearic acid, use not too much lye during saponification.
3. Choosing the Right Oils
You can prevent white spots on soap by selecting suitable oils in addition to temperature control and proper mixing. Oil-related issues can cause various white spots.
4. Proper Temperature Management
There are different soap production temperatures, depending upon formula, climate, and personal preference, but for ash-free soap, optimal temperatures between 95 and 110°F (35 and 43°C) are recommended.
5. Using a Soap Recipe with Balanced Additives
A balance of soap additives, temperature, air exposure, and proper mixing can keep white spots at bay, which can arise from various sources, and a good recipe addresses these issues.
How to Remove White Spots on Soap?
The good news is that the white spots on soap are not only nontoxic, but they're also usually removed using the methods listed below:
1. Scraping Off Soap Ash
Apparent white spots on homemade soap can be solved by scraping in addition to other alternative techniques which are more effective, primarily due to soda ash or air pockets.
2. Rebatching Soap
Rebatching is a process that melts grated soap, removes contaminants like stearic acid spots, and re-emulsifies fatty acids, allowing the soap to cool and cure before use.
3. Buffing and Smoothing Soap
Buffing and smoothing can effectively remove or conceal white spots on soap. However, the outcome depends on the initial cause, and is only a short-term solution for deeper-set spots.
Conclusion
White spots are the result of soda ash, excessive glycerin, lye, or fragrance additives used in the recipe. Preventing and removing spots requires proper curing conditions and balanced ingredients, among other methods. Stearic acid and soda ash are also responsible for white spots in cold process soap.
