Making Cold Process Soap With Litsea Cubeba: The Citrus That Survives Saponification
Most citrus essential oils have a problem in cold process soap. They fade. Sometimes they vanish entirely within days of unmolding, leaving you with a beautiful bar that smells of almost nothing. Litsea cubeba is different, and that difference is worth understanding before you invest time and ingredients into a batch.
Litsea cubeba oil (also sold as may chang oil) is steam-distilled from the small pepper-like fruits of Litsea cubeba, a shrub native to subtropical Asia. Its high citral content (often 75 to 85 percent) gives it a sharp, clean lemon-like brightness. That same citral content is also what allows it to hold up through the alkaline saponification process far better than cold-pressed lemon or sweet orange oil. The result: a finished litsea cubeba soap with a genuine, lasting citrus character.
This guide walks through a full cold process recipe, including the why behind ingredient choices, realistic batch sizing for home crafters, and honest safety information you actually need.
Before You Start: A Note on Citrus in Cold Process Soap
If you have tried adding lemon or grapefruit essential oil to cold process soap before, you already know the disappointment. Cold-pressed citrus oils are composed largely of monoterpene hydrocarbons (primarily limonene), which do not survive the high-pH saponification environment. The scent breaks down rapidly.
Litsea cubeba succeeds where those oils struggle because its dominant aromatic compounds are aldehydes (citral being the main one), not terpenes. Aldehydes behave differently under alkaline conditions. They are not indestructible, but they are substantially more stable. Soapers who have made side-by-side comparisons consistently report that may chang soap retains a noticeable citrus scent for weeks to months, while cold-pressed citrus bars are often scentless by week two.
One caveat worth mentioning: litsea cubeba can accelerate trace in cold process soap. It will not always cause a dramatic acceleration, but you should work with this in mind and avoid techniques that require a long, fluid trace (such as intricate in-pot swirls). Stick to simpler pours, textured tops, or dividing your batter for a two-color pour.
Recipe Overview
| Detail | Information |
|---|---|
| Difficulty | Intermediate (some cold process experience recommended) |
| Active prep time | Approximately 60 to 90 minutes |
| Cure time | 4 to 6 weeks minimum |
| Yield | Approximately 8 to 10 bars (depending on mold and cut) |
| Total oil weight | 500 g (approximately 17.6 oz) |
Equipment You Will Need
- Digital kitchen scale (accurate to 1 gram)
- Two heat-safe pitchers or containers (stainless steel or heavy-duty plastic, minimum 1-liter capacity each)
- Long-handled stainless steel or silicone spoon
- Stick blender (immersion blender)
- Instant-read or infrared thermometer
- Loaf mold or individual bar molds (silicone preferred for easy unmolding)
- Dedicated soap-making spatulas (never reuse for food)
- Safety goggles or glasses
- Chemical-resistant gloves (nitrile or rubber)
- Long-sleeved clothing
- Soap cutter or sharp knife
- Well-ventilated workspace
Safety first, always. Sodium hydroxide (lye) is a caustic alkali that causes serious chemical burns on contact with skin, eyes, and mucous membranes. Keep pets and children out of your workspace. Have a bottle of white vinegar nearby (it can help neutralize lye spills on surfaces). Never make cold process soap without appropriate protective equipment. If lye contacts your skin, flush immediately with large amounts of cool running water.
Ingredients
The Oil Blend (500 g total)
| Oil | Weight | Percentage | Role in the Bar |
|---|---|---|---|
| Coconut oil (76 degree) | 175 g | 35% | Cleansing, lather, hardness |
| Olive oil (pomace or regular) | 175 g | 35% | Conditioning, creaminess, bar longevity |
| Palm oil (RSPO certified) or lard | 100 g | 20% | Hardness, stable lather |
| Castor oil | 50 g | 10% | Lather boosting, skin feel |
A note on palm oil: if you prefer to avoid it, substitute a combination of shea butter (75 g) and lard or tallow (25 g), or simply increase your olive oil to 200 g and use 75 g of shea butter. Each substitution will change your lye calculation, so always run your final oil blend through a lye calculator before proceeding.
Lye Solution
- Sodium hydroxide (NaOH), food or soap grade: 69.5 g (calculated at 5% superfat using SoapCalc or similar)
- Distilled water: 165 g (33% water as percentage of oil weight)
Always verify your lye amount using a reliable lye calculator such as SoapCalc, Brambleberry's lye calculator, or Soap Guild tools. Do not skip this step. Lye amounts vary by oil type, and the figures above are specific to the oil blend as written. Any substitution requires a recalculation.
Fragrance
- Litsea cubeba essential oil: 15 g (3% of total oil weight)
Three percent is a widely used usage rate for litsea cubeba in cold process soap. IFRA guidelines and industry practice generally support up to approximately 3 to 4% in rinse-off products, but using the lower end reduces the risk of acceleration and skin sensitivity. Do not exceed 3% in your first batch.
Optional Colorants
- Yellow oxide or lab-certified cosmetic yellow mica: 1 to 2 teaspoons dispersed in 1 tablespoon of light liquid oil
- Dried litsea cubeba berries or lemon zest for top decoration (decorative only; do not use materials that can mold inside the bar)
Step-by-Step Instructions
Step 1: Prepare Your Workspace and Weigh All Ingredients
Set up your workspace in a well-ventilated area. Put on your gloves and goggles now, before you open anything. Weigh all oils, the sodium hydroxide, and the distilled water into separate containers. Measure your litsea cubeba essential oil and set it aside in a small covered container. If using colorant, disperse it in a small amount of liquid oil now so it is ready to add at trace.
Step 2: Make the Lye Solution
Add the sodium hydroxide crystals slowly to the distilled water. Never pour water into lye. The mixture will heat rapidly to temperatures above 200°F (93°C) and release fumes. Stir gently until all crystals dissolve completely. Set the lye solution aside in a safe, stable location to cool. Allow it to cool to approximately 90 to 110°F (32 to 43°C) before proceeding.
Step 3: Melt and Combine Your Oils
Gently melt coconut oil and palm oil (if solid) until just liquefied. Add olive oil and castor oil. Allow the combined oils to cool to approximately 90 to 110°F (32 to 43°C). You want your lye solution and your oils to be within about 10 degrees of each other when you combine them. Precise temperature matching is less critical than it once was taught, but having both components in a similar range reduces the risk of overheating or ricing.
Step 4: Combine Lye and Oils
Pour the lye solution slowly and carefully into your oils. Do not pour the oils into the lye. Using your stick blender (turned off), stir briefly to combine. Then pulse with the stick blender in short bursts, alternating with hand stirring, until you reach a light trace. Light trace looks like a thin pudding or melted ice cream. Stop here. Do not let it thicken further before adding your essential oil, because litsea cubeba can accelerate the process.
Step 5: Add Colorant and Litsea Cubeba Essential Oil
Add your dispersed colorant (if using) and stir in by hand. Then add the 15 g of litsea cubeba essential oil and fold it in quickly with a spatula. Use a few short pulses of the stick blender if needed to fully incorporate, but watch your batter carefully. If it begins thickening fast, move immediately to pouring.
Step 6: Pour Into the Mold
Pour your batter into the mold steadily. Tap the mold on the counter a few times to release air bubbles. Texture the top with a spoon or spatula if you like, or leave it smooth. If you want to add decorative dried berries to the top, do so now, pressing them in lightly.
Cover the mold with a piece of cardboard or a light towel. Some soapers insulate at this stage to encourage full gel phase (which deepens color and can enhance scent retention). If you prefer a lighter, ungelled bar, place it in a cool area or even a cool oven (turned off) to discourage gel.
Step 7: Unmold and Cut
Wait 24 to 48 hours before attempting to unmold. Litsea cubeba soap may unmold a little faster than some other bars due to its behavior at trace, but do not rush it. If the bar still feels soft or sticky, leave it another 24 hours. Once unmolded, cut into individual bars using a soap cutter or sharp knife.
Step 8: Set
Place bars on a rack with space between each bar for air circulation. Store in a cool, dry location out of direct sunlight. Allow to set for a minimum of 4 weeks. Six weeks produces a harder, longer-lasting bar with a more developed scent profile. Do not rush the setting period. Freshly made cold process soap still contains unreacted lye and is not safe to use until setting is complete.
Safety Warnings and Skin Sensitivity Information
Lye Safety
Sodium hydroxide is not an ingredient to approach casually. Keep a first-aid protocol in mind before you begin: flush any skin contact immediately with large amounts of running water for at least 15 minutes. Eye contact requires the same immediate flushing and prompt medical attention. Store unused lye in a sealed, airtight container away from moisture and children.
Essential Oil Safety
Litsea cubeba essential oil contains high levels of citral, which is a known skin sensitizer in undiluted or high-concentration exposure. At the 3% usage rate recommended in this recipe, the finished soap is a rinse-off product with appropriate dilution. However, individuals with known citrus sensitivities should patch-test the cured bar before regular use.
To patch-test: After full setting, work up a small lather on the inner forearm and rinse. Wait 24 hours and observe for any redness, itching, or irritation. If any reaction occurs, discontinue use.
People who are pregnant, nursing, or have specific skin sensitivities should consult a qualified healthcare provider before using new personal care products. This recipe is formulated for use by adults.
Children and Pets
Keep children and pets out of the soap-making workspace entirely during active production. The finished bars are intended for adult use. Essential oils, including litsea cubeba, are not appropriate for use on infants or very young children without specific professional guidance.
Storage Instructions and Shelf Life
Store fully set litsea cubeba soap bars in a cool, dry place with good air circulation. Avoid sealed plastic bags or airtight containers during long-term storage, as trapping moisture shortens bar life and can encourage the development of soda ash on the surface (a harmless white coating, but visually less appealing).
When in active use, keep your bar on a well-draining soap dish that allows water to run away from the bar. Standing water dissolves the bar faster and can cause a mushy, short-lived bar.
Shelf life depends primarily on your oil selection. The olive oil in this recipe is relatively stable, but the high unsaturated fat content can eventually lead to rancidity (identified by a waxy or crayon-like smell often called DOS, or dreaded orange spots). Bars made with this formula typically have a comfortable shelf life of 12 to 18 months when stored properly. Adding a small amount of rosemary antioxidant (ROE) to your oils at the blending stage can extend this.
Variations and Substitutions
Scent Variations
Litsea cubeba blends well with several other essential oils that also hold reasonably well in cold process soap. Consider using a blend rather than litsea alone for added depth. Some combinations worth exploring:
- Litsea cubeba and cedarwood: Woody citrus, grounded and clean. Use 10 g litsea cubeba and 5 g cedarwood atlas.
- Litsea cubeba and lemongrass: Bright, green-citrus character. Use 10 g litsea cubeba and 5 g lemongrass. Note that lemongrass can also accelerate trace.
- Litsea cubeba and lavender: Softer, more rounded. Use 10 g litsea cubeba and 5 g lavender 40/42.
- Litsea cubeba and black pepper: A sharp, spicy citrus bar. Use 12 g litsea cubeba and 3 g black pepper.
For a deeper look at how litsea cubeba pairs with other essential oils and aromatic materials, the guide to blending with litsea cubeba covers accord building and which notes hold best alongside it.
Oil Blend Variations
Palm-free version: Replace the 100 g of palm oil with 75 g of shea butter and 25 g of additional coconut oil. Recalculate your lye amount before proceeding. This bar will be slightly softer at unmolding and benefits from a full 6-week setting period.
High-olive version (Castile-style): Increase olive oil to 450 g and reduce coconut oil to 50 g, eliminating palm and adjusting castor oil to remain at 10%. Recalculate lye. This bar will take 6 to 8 weeks to set properly and will feel different in use (gentler lather, softer feel). The litsea cubeba scent still holds well in a high-olive base.
Goat milk version: Substitute goat milk for part or all of the distilled water. Freeze the milk before adding lye to prevent scorching and discoloration. Milk soaps often produce a creamier bar. The litsea cubeba citrus note contrasts nicely with the naturally milky quality of the base.
Colorant Variations
Yellow oxide and yellow mica are the most obvious choices for a citrus bar. For a more muted, natural look, a small amount of turmeric (1/4 to 1/2 teaspoon in the batch) gives a warm golden hue that fades to a soft cream over time. Activated charcoal at 1 teaspoon per pound of oils creates a graphite-toned bar that makes the bright citrus scent feel unexpectedly sophisticated.
Troubleshooting Common Issues
Acceleration
If your batter seizes or thickens very rapidly after adding the essential oil, do not panic. Use your spatula to scoop it into the mold as best you can. Smooth the top as much as possible. The bar may be rustic-looking but it will still be a good, usable soap. Next batch: try soaping at a slightly cooler temperature (around 85°F / 29°C), and add your litsea cubeba essential oil at a thinner trace.
Soda Ash
A white, powdery or chalky film on the surface is soda ash. It is harmless and washes off easily in the shower. It forms when the surface of the batter reacts with carbon dioxide in the air during the saponification process. To minimize it, cover your poured batter promptly and consider lightly spraying the surface with 91% isopropyl alcohol immediately after pouring (before covering).
Soft or Sticky Bar After 48 Hours
High olive oil content or a high water percentage can both result in a slower-hardening bar. Give it more time before cutting. If after 72 hours it still feels very soft, place the entire mold (uncovered) in the freezer for one hour, then allow it to return to room temperature before unmolding. This technique, common with milk soaps and soft-oil-heavy batches, firms the bar enough to cut cleanly.
Beyond the Bar: More Ways to Work With Litsea Cubeba
Soap is a wonderful starting point, but litsea cubeba performs beautifully across a range of handcrafted products. If you have fallen for this oil's distinctive citrus brightness, there are other projects worth exploring. The litsea cubeba candle guide covers wax selection and fragrance loading rates for soy and coconut wax blends. For a faster afternoon project, the litsea cubeba room spray recipe uses just a few ingredients to bring that clean, citrus character into any space without the saponification chemistry.
A Few Final Thoughts on This Oil
Making citrus soap that actually smells like citrus after setting is one of those small victories that cold process soapers remember. Most beginners hit the scent-fade problem with standard citrus oils, shrug, and move on to lavender. Discovering litsea cubeba changes that. It is not a perfect replication of a cold-pressed lemon oil (the scent profile is slightly more complex, a little greener, less sweet), but it is genuinely, stubbornly citrus. After six weeks of setting, a well-made may chang soap bar still has presence.
Take notes on your batch. Record your temperatures, the timing of trace, how quickly the essential oil moved things along. Cold process soap rewards the people who pay attention, and litsea cubeba is an oil worth paying attention to.