Combining Oils and Lye Solution to Reach Trace

Prepare uniform oils, coordinate temperatures and blend gently until the plain batter reaches an appropriate pourable trace.

Part 6 of 10 | Soap Making from Scratch Using Caustic Soda and Oils

Learning goals

Prepare the specified oils without changing their proportions, combine them with the verified solution and use an immersion blender without splashing. Distinguish a stable emulsion and trace from thickening caused by cooled solid fats. Record observations instead of using a fixed blending time as proof of success.

Before you begin

Use only the reviewed Part 3 formula and the solution prepared in Part 5. Keep full eye and skin protection on. The supervisor should confirm that both component records are complete and no material was lost. Do not add scent, colour, sugar, salt or another ingredient to accelerate or decorate the batch.

Step 1 Prepare uniform oils

The weighed oils are 226.8 g ordinary coconut oil, 425.2 g ordinary olive oil and 311.8 g refined palm oil. Gently melt solid fats using compatible equipment and a controlled heat source. Do not heat the lye solution. Avoid smoke and excessive heating, and keep water from entering the oil vessel.

Ensure the palm supply was homogenised before the recipe portion was taken. Combine the verified oil portions in the main mixing vessel and stir until uniform. Check that no unmelted solid pieces remain. Do not scrape an unweighed extra amount from the supplier bottle into the mixture after the recipe masses have been confirmed.

Step 2 Coordinate working temperatures

For this recipe, aim for both the oils and solution around 49 degrees Celsius, neither above 54 degrees Celsius, and within about 5 degrees of each other. These are practical conversions of the source project's temperature guidance. Measure rather than estimating with your hand, and record both actual readings.

Keep the oils fully liquid. If they have cooled and begun to form opaque solid streaks, resolve that with the supervisor before adding lye. A solidifying fat can make a mixture look thick without demonstrating proper emulsification. Do not force the recipe into a very cold or unusually hot method because another online tutorial uses it.

Step 3 Prepare the blender before combining

Check the immersion blender is suitable, its head is securely fitted and its cord is clear of liquid and the work route. Keep it off while placing the head into the oils. Tilt it gently as appropriate to release trapped air, then keep the blade fully submerged with adequate liquid above it.

Do not run the blender while lifting it out or testing it in air above the vessel. Keep hands away from the blade and disconnect power before touching or cleaning the head. A large mixing vessel with headroom helps contain the process, but it does not make careless blending safe.

Step 4 Combine slowly and deliberately

With the blender off, slowly pour the reviewed lye solution into the oils, keeping the stream low and controlled. Use the vessel's handle or intended grip with appropriate protection. Do not chase the last drop if doing so makes the grip unstable. Do not rinse residual solution into the oils with extra water.

Once combined, pulse the submerged blender briefly, then stir with it switched off or use the compatible spatula. Alternate short pulses and gentle stirring. Follow the blender's operating limits so the motor does not overheat. Keep the head submerged whenever powered and avoid splashing the caustic batter.

Step 5 Observe emulsion and trace

Look for a uniform batter without a visible oil slick or separate watery layer. As it thickens, a small amount drizzled back onto the surface can leave a brief trail. Stop at a light to medium, still-pourable trace for the simple mould. Do not continue until it becomes difficult to handle simply to make the trail look dramatic.

Timing varies with the oils, equipment and temperature. The source recipe's example blending time is not a universal countdown. If the mixture appears thick but grainy or shows solid-fat streaks, consider false trace and ask the supervisor to review it. If it separates or behaves unexpectedly, keep it contained and do not invent an extra-lye or extra-oil correction.

Step 6 Prepare the handoff to pouring

Set the switched-off blender in the designated compatible catch vessel and keep its contaminated surfaces controlled. Check the mould, tray and resting location again. The batter remains potentially caustic even though it looks creamy and soap-like, so gloves and splash protection remain necessary.

Record component temperatures, blending observations and the appearance at the stopping point. Note any unexpected behaviour while it is fresh in memory. Do not taste the batter, touch it with bare skin or ask another person to judge it by a skin sensation. Continue to Part 7 only with a uniform, reviewed batch and clear work route.

Guided exercise

1. Verify the oil identities and masses, then prepare a fully liquid, uniform mixture without adding unweighed material.

2. Measure and record both component temperatures and confirm the recipe's working conditions with the supervisor.

3. Rehearse blender placement while it is off, keeping the blade submerged and the cord safely routed.

4. Combine the solution and oils, then alternate short blending pulses and gentle stirring until reviewed pourable trace.

5. Record the appearance and transfer readiness. If the batch separates or composition is uncertain, document a hold instead of proceeding normally.

Knowledge check

1. Is thickening always proof of stable trace?

2. Should the blender run while being lifted out of batter?

3. Is traced batter safe to touch with bare hands?

Answer guide

1. No. Cooling fats can cause misleading thickening and other problems require review.

2. No. Switch it off and keep powered blades submerged to prevent splashes.

3. No. Treat it as potentially caustic and maintain protection.

Completion standard

Show accurate component and temperature records, controlled blending and a reviewed uniform pourable batter. No timed guess, bare-skin test or added correction may substitute for observing the actual batch. Unresolved separation or false-trace concerns keep the project on hold.

Sources and verification notes

Bramble Berry Simple and Gentle Soap Project. Checked 17 September 2026. Published plain beginner formula: 8 oz coconut oil, 15 oz olive oil, 11 oz palm oil, 4.8 oz NaOH and 11.2 oz distilled water, by mass. Course metric adaptation and omissions are documented in SOURCES.md. The published recipe is not a laboratory validation of a learner batch.

Bramble Berry Lye Safety Guide. Checked 17 September 2026. Supplier guidance on protective equipment, ventilation and adding lye to water. This course selects compatible stainless steel or manufacturer-rated plastic, excludes glass for lye and does not recommend acid neutralisation of spills by a beginner.