Here is an industrial secret that most soap buyers never learn: when oil reacts with sodium hydroxide to form soap, it also produces glycerin. Not as an additive. As a natural byproduct of the saponification chemistry. For every hundred grams of oil that becomes soap, approximately eight to ten grams of glycerin forms alongside it.
Glycerin is one of the most effective humectants in skin care — a compound that draws moisture from the surrounding air and holds it on the skin surface. It is used in moisturisers, serums, and hundreds of skin care products. It is also sold as a standalone ingredient to cosmetic manufacturers.
Industrial soap manufacturers extract this glycerin from their soap. They sell it to the cosmetics industry. Then they add synthetic humectants — propylene glycol, polyethylene glycols — back into the soap to partially replace the moisture-holding effect they removed. The consumer pays for soap that had a natural moisturiser removed from it, then had a synthetic replacement added back.
Natural soap makers retain the glycerin.
What retained glycerin does for skin
Glycerin is a humectant — it does not provide moisture itself but draws moisture to the skin from the environment. In a bar of Avlia Aleppo soap, the retained glycerin is distributed throughout the bar. Every use delivers a small amount of glycerin to the skin surface. This is why washing with a natural olive oil soap leaves skin feeling different from washing with a commercial SLS-based bar — the commercial bar strips moisture, the natural bar delivers glycerin alongside cleansing.
The visible difference in use
People who switch from commercial soap to Avlia often notice within the first week that their skin feels moisturised after washing rather than requiring immediate moisturiser application. The most visible effect is in the post-wash period. Commercial soap users reach for body lotion immediately after drying because their skin feels tight and dry. Avlia users frequently find they no longer need body lotion after using the Avlia 5% or 10% Bar as a daily body wash. The glycerin and olive oil together are doing the moisturising work that the lotion was compensating for.
Which Avlia bars retain the most glycerin
The glycerin content of any Avlia bar is directly proportional to the oil content. The Avlia 100% Olive Oil Bar and the Avlia 5% Bar, being predominantly olive oil-based, produce the highest relative glycerin content. Higher-laurel bars still retain their full glycerin complement — the glycerin is a product of all saponified oil, both olive and laurel — but the olive oil-dominant bars deliver slightly more per gram of soap used.
The commercial extraction: an economic calculation
Industrial soap manufacturers sell extracted glycerin at approximately twice the price per gram that they pay for the oil it came from. Extracting glycerin from every batch of industrial soap is an economically rational decision for large-scale producers. It makes the soap cheaper to make and creates a secondary revenue stream from the byproduct.
For Avlia’s Syrian Sabonji artisans in Turkey, the calculation is different. The traditional Aleppo soap process is about making the best possible bar, not optimising an industrial byproduct stream. The glycerin stays where it belongs: in the soap, on your skin.
Find the full Avlia range at avliahome.com.