How to Make Essential Oil

Purchase essential oil distillation equipment. Although it can be challenging to find this equipment in stores (unless you have a specialized shop nearby), you can easily buy it online. However, be aware that it can be quite costly, often amounting to several million VND. If you plan to produce essential oils in large quantities, investing in professional distillation equipment may be worthwhile.

If you prefer not to purchase, you can create your own distillation setup. There are numerous ways to assemble a distillation apparatus, with thousands of designs available. Many modern setups are even homemade. The essential components of a distillation device include:

• A heat source, typically direct flame
• A pressure cooker
• Glass tubing with a 10 mm diameter
• A container for cold water to cool and condense the steam passing through the tube
• A separator to isolate the essential oil from other substances you don’t want in your final product

Whenever possible, use stainless steel and glass components. Avoid using plastic tubing instead of glass, as it may compromise the quality of the essential oil. Some plants react poorly to copper, though heavily tinned copper is suitable in most cases. Aluminum can also be used, but avoid it for plants like bay, clove, or those whose oils contain phenols.

Bend the tubing to pass through the cooling container. Place the medicinal plants in the pressure cooker to heat, and the steam will be directed into the tubing. You can cool the steam into liquid by submerging the tubing in cold water or ice. Depending on your cooling container, shape the tubing accordingly. For example, if using a simple basin, coil the tubing inside it. If using a wide ice bucket, bend the tubing at a 90-degree angle to guide it from the bucket’s edge to a hole at the bottom.

Connect the tubing to the pressure cooker valve. Use a short, flexible hose with a diameter close to 10mm to fit both open ends. Secure the connection with a pipe clamp available at hardware stores.

• Ensure the hose is long enough to allow bending. Otherwise, the tubing will stick straight up, and you’ll need enough space to bend it at a 90-degree angle into the cooling container.

Insert the tubing into the cooling container. If using a basin, coil the tubing entirely inside, ensuring it’s submerged when filled with cold water or ice. If using a bucket, drill a small hole at the bottom to insert the tubing. Seal any gaps around the hole with silicone or epoxy to prevent leaks.

Insert the tubing into the separator. Once the distillate drips into the separator, it will handle the rest of the process for you. It will isolate the essential oil from other unwanted substances, ensuring purity in the final product.

Ensure all equipment is securely positioned. Depending on the tools you use and the shape of the tubing, you may need to create a stable setup for the distillation apparatus. Place the lid with attached tubing onto the pressure cooker, guide the tubing into the cooling container, and insert the tubing into the separator. Make sure the tubing is bent at an appropriate angle and that no equipment is at risk of tipping over.

Determine the optimal harvest time for the plant material. The amount of essential oil in a plant depends on its growth stage, so harvesting at the right time is crucial. Research the ideal harvest period for the specific plant you’re distilling. For example, lavender should be harvested when about half of its flowers have wilted, while rosemary is best harvested when it’s in full bloom.

Harvest correctly. When researching the best time to harvest for maximum essential oil yield, also study the proper harvesting techniques. Careless handling, harvesting the wrong parts of the plant, or picking at the wrong time of day can reduce both the quantity and quality of the oil. For instance, only the flowering parts of rosemary are needed for essential oil production. Discard or repurpose the rest of the plant.

• Most essential oils are found in oil glands, leaf veins, and trichomes, which are delicate. Disturbing or damaging these parts will yield less oil. Handle the plant gently and minimize movement as much as possible.

Choose plants carefully when purchasing. If you buy pre-harvested plants, you lose control over the harvesting process. Opt for plants that appear healthy and undamaged, and ask the seller about the harvest time. Typically, whole plants (not crushed or powdered) are the best choice.

• While distillation removes many impurities, herbicides and pesticides can contaminate your oil. Therefore, it’s best to use organically grown plants, whether you grow them yourself or purchase them.

Dry the plant material. Drying reduces the oil content per plant but can significantly increase the oil yield per distillation batch due to the larger quantity of plant material used. Dry the plants slowly and avoid direct sunlight. Plants like lavender and mint, grown for commercial purposes, are often left to dry in the field for about a day after cutting.

• The ideal drying method varies by plant, but generally, avoid excessive heat. Dry in shade or even in a dark room to minimize oil loss.
• Avoid wetting the plants before distillation. Distill them immediately after drying.
• You may skip the drying step if you prefer to use fresh plant material.

Fill the distillation pot with water. If you’ve built your own distillation setup, the main pot is your pressure cooker. Use clean water, preferably filtered or distilled, and the softest water available. If using an industrial still, follow the manufacturer’s instructions. Otherwise, ensure you have enough water to complete the distillation. Depending on the type and quantity of plant material, distillation can take anywhere from half an hour to six hours or more after the water boils.

Add the plant material to the water until the pot is full. While there must be enough water to prevent boiling dry, ensure the plants are secure and not obstructing the steam’s path through the tubing attached to the pressure cooker lid. Leave a few centimeters of space in the pot for comfort.

• There’s no need to chop or prepare the plants further; doing so may lead to oil loss.

Heat the pressure cooker. Tighten the lid so that steam is forced through the tubing connected to the steam valve. Most plants release their essential oils at 100°C or 212°F, the boiling point of water.

Monitor the distillation process. After heating for a while, the distillate will pass through the condenser and into the separator. While you don’t need to intervene, you should check to ensure the water doesn’t run dry. Depending on the distillation duration, you may need to replace the water in the cooling container. If the tubing heats up and warms the water, replace it with fresh cold water or ice to maintain the cooling process.

Filter the collected essential oil (optional). Once distillation is complete, you can filter the oil using a cheesecloth or similar dry cotton fabric. Ensure the cloth is clean and dry, as residual detergents or dirt can spoil the oil.

• Don’t be discouraged if you obtain only a small amount of oil from a large quantity of plant material. Yield rates vary by plant and are often lower than first-time distillers expect.

Transfer the essential oil into bottles as quickly as possible. Most essential oils have a shelf life of at least one to two years, though some expire sooner. To maximize shelf life, store them in opaque glass or stainless steel bottles. Use a clean funnel to pour the oil into the containers, ensuring they are thoroughly cleaned beforehand. Keep the oils in a cool, dark place.

• Decide what to do with the hydrosol. Another byproduct collected in the separator is hydrosol, distilled water infused with the plant’s essence.
• Some hydrosols, like rose water and lavender water, are usable.
• If you don’t want to keep the hydrosol, you can pour it back into the distillation pot for the next batch, provided distillation occurs shortly after. Otherwise, discard it.