The banana (Musa acuminata) is one of the most widely consumed fruits in the world, grown across tropical regions of Central America, South America, Southeast Asia, and Africa. At Eternal Sunday, we use fresh banana puree as part of the liquid phase in our Nightwood Soap, blended with water before being combined with lye to begin saponification. It's a straightforward ingredient used in a deliberate way, sourced fair trade from Central America.
Why banana in soap
Banana is rich in natural sugars, potassium, and vitamins A, B6, and C. In cold-process soap-making, fruit purees introduce these compounds into the formula from the very beginning of saponification. The natural sugars in particular interact with the lye during mixing, generating additional heat and contributing to a denser, creamier lather in the finished bar.
The effect is subtle but present. A soap made with fruit puree in the liquid phase tends to have a softer, more conditioning skin feel than a water-only equivalent, and the lather tends to be creamier rather than bubbly. Given the other ingredients in Nightwood (olive oil, shea butter, avocado oil, cocoa butter), banana puree reinforces a formula already oriented toward conditioning rather than stripping.
How we use it
We blend fresh banana to a smooth puree and combine it with water, using the mixture as the liquid phase for dissolving the lye. In Nightwood, banana puree makes up roughly one third of the total liquid phase, with water making up the remainder. This ratio gives the benefits of a fruit-based liquid without the instability that can come from using puree at full concentration, where very high sugar content can cause the batter to overheat and seize.
The lye is added to this blended liquid, not the other way around, a standard safe practice for cold-process soap-making. The mixture heats significantly on contact, more so than water alone because of the sugars, and is then combined with the oils and butters to begin saponification.
What happens to the banana during saponification
By the time Nightwood has cured, there is no detectable banana scent or colour in the finished bar. The essential oil blend of cedarwood, frankincense, juniper berry, and vetiver dominates the scent entirely, and the caramel clay we add to the batter gives the bar its colour. The banana has done its work in the liquid phase and been transformed through saponification, present in the bar's character rather than its surface qualities.
Fair trade sourcing
We buy fair trade bananas, the same standard we apply to any ingredient where supply chain labour practices are a known concern. Banana production in Central America has a well-documented history of difficult labour conditions on large commercial plantations. Fair trade certification provides independent verification that the farmers and workers involved meet baseline standards for pay and working conditions. It's a minimum bar, not a complete answer, but it's the one we can verify and act on.
In our products
Banana currently appears in our Nightwood Soap, where it contributes to the liquid phase alongside water. It's an ingredient we return to when a formula calls for the particular lather quality and skin feel that a fruit puree brings, and one we may use in other formulas in the future.
