Essential oils are extracts from the roots, stems, leaves, bark, flowers, wood and resin of plants. They are highly concentrated oils consisting of volatile chemical compounds that contain the essence of the source from which they are extracted.
Essential Oil Safety
As many soap makers are inclined to create other products such as bath bombs, body scrubs, lotions and creams etc. it is important to note that all essential oils should be diluted in either a carrier oil or in a product before applying to the skin.
We tend to create both leave-on products (creams and lotions), wash off products (sugar scrubs, bath salts, bath bombs) and cold process soap. All leave-on products have the lowest allowable usage rate and cold process soap has the highest.
This is so very important to understand as EOs determined usage rate should be followed for optimal safety.
An excellent resource for determining the safe usage for essential oils is eocalc.com.
When making cold process soap the outcome of the scent will obviously depend on your preference and the particular percentages used incorporating Top, Mid and Base note scents.
Decide on Your Scent
As there is a plethora of plants, essential oils are created in an exhaustive variety of scent bases. These may include herbal, woody, floral, citrus or spicy scents.
Adding the Essential Oil
Some scents are more fragile and can often lose their stickability due to the pH level in soapmaking (citrus and light florals mostly) and therefore it is advised to add EOs towards the end of your soap making or anchor the EO to enable a longer lasting result.
As with all other ingredients in creating cold process soap, the EOs are weighed (grams) and not added according to the mL.
The recommended EO use in cold process soap is no greater than 3%. This will also depend on the concentration of the oil. In more concentrated options (usually the base notes) you should only consider around 1-2%. A good rule of thumb in producing a well-rounded blend of oils for cold process soap are:
30% blend for the top note
60% blend for the middle note
10% blend for the base note
Adding an Anchor for Scent
Essential Oils are often expensive as well as being notorious for disappearing once the soap is cured, so it is good to add an anchor to help retain it.
Kaolin Clay (see my blog post for the benefits of clay in your soap) is a great anchor for the EO to adhere to whilst the soap is curing. I usually mix the EO into either Kaolin or Pink clay (any clay is good) at least an hour (overnight is preferable) prior to placing into the soap batter. The clay soaks up the scent and enables it to remain long past the cure.
Essential oils that tend to evaporate faster are classified as top notes and form the first impression and hit of fragrance of the soap. The fleeting top note scent is fresh, bright and uplifting.
Examples of Top Notes (not an exhaustive list)
Citrus (Lemon, Lime, Orange, Sweet Orange, Bergamot, Grapefruit, Mandarin & Tangerine)
Herbs & woods (Lemon Verbena, Citronella, Basil, Thyme, Sage, Melissa, Clary Sage Fennel, Coriander, Lemongrass) * Birch * Anise Wintergreen * Chamomile * Saffron * Cedarwood Atlas * Eucalyptus * Tea Tree * Peppermint * Spearmint
Middle notes are subtle scents tending to be warm and soft fragrances that generally give body to the blend. They are usually described as giving your soap the 'heart' of the scent and remaining longer on the skin.
Examples of Mid Notes (not an exhaustive list)
Angelica * Bay Laurel * Black Pepper * Lavender * Palmarosa * Petitgrain * Fennel Cardamom * Champa * Clove * Hyssop * Jasmine * Tumeric * Cinnamon * Geranium
Violet Leaf * Neroli * Bois de Rose * Marjoram * Pine * Rosemary * Nutmeg * Yarrow
Rose Geranium * Tarragon * Spruce * Juniper * Myrtle
Base oils remain much longer than the top and mid note oils and are more intense fragrances that tend to linger longer and bring a richness and depth to your blend.
Examples of Base Notes (not an exhaustive list)
Cedarwood * Clove * Amber Musk * Frankincense * Ginger * Oakmoss * Sandalwood
Spikenard * Tuberose * Rose * Peru Balsam * Myrrh * Patchouli * Rosewood * Vanilla
Vetiver * Tonka Bean * Ylang Ylang
Blending Essential Oils for Soapmaking
As mentioned above, each EO has its own recommended safe usage rate which is usually indicated in the description of the EO when purchasing.
If you would like a well-rounded, balanced scent, try to incorporate a Top, Mid and Base note oil scent when creating your blend.
This doesn't mean that you need to add only three scents - you can add group blends by using a couple of top, mid or base notes to create the blend. It all depends on your particular preference.
This Goes with That
The endless combinations achieved in blending EOs are only limited by your preference, so it is best to try a few blends until you come up with the blend of scents that suits you. Here are a few examples of good blend options.
Lavender - blends well with: Clary Sage; Basil; Lemon; Geranium; Patchouli; Rosemary; May Chang; Peppermint; Lime
Clary Sage - blends well with: Geranium; Lavender; Lime; Vetiver; Cedarwood; Sandalwood
Rosemary - blends well with: Citronella; Ginger; Geranium; Grapefruit; Tea Tree; Lime; Spearmint
Lemon - blends well with: Lavender; Chamomile; Ginger; Eucalyptus; Peppermint
Peppermint - blends well with: Lavender; Spearmint; Pine; Marjoram; Rosemary; Lemon
The Masculine Blend
Bergamot, Saffron, Cedarwood & Patchouli
The Feminine Blend
Geranium, Palmarosa & Bergamot
The Love Blend
Clary Sage, Patchouli & Ylang Ylang
The Woods Blend
Orange, Juniper & Peru Balsam
The Spa Blend
Eucalyptus, Rosemary & Cedarwood
The Uplift Blend
Grapefruit, Lime & Lemon
The Relaxing Blend
Chamomile, Lavender, & Patchouli (or Oakmoss)
Lavender, Cedarwood & Frankincense
Lavender, Clary Sage, Cypress & Thyme
I would be interested in your comments regarding the blends that you have found excellent. Let me know how you go with your blends.