Most soap you buy was made a few weeks ago. A traditional Aleppo bar was probably made last winter. After cooking, the bars are stacked in open towers and left to dry for six to nine months or more (UNESCO).
Why wait so long? And does a soap that old ever go off? This guide explains what curing does, why the outside turns gold, and how to store a bar. For the full process, see how Aleppo soap is made.
Key takeaways
- The soap forms in days. About 99% of saponification happens in the first 48 hours (Lovely Greens).
- Curing is mostly drying. Water leaves, and the bar hardens (Lovin Soap).
- Aleppo bars dry for 6-9 months or more and lose about 30% of their weight (UNESCO; Najel).
- The gold crust is oxidation; the core stays green (Wikipedia).
- Soap keeps for years if dry; orange spots signal rancid oils (Soap Queen).
The short answer
Aleppo soap is cured for months because the freshly made soap is soft and full of water. The chemical reaction is done within days; the long cure lets water evaporate so the bar becomes hard, dense and slow to dissolve. As it dries, the outside oxidises to pale gold while the inside stays green. A well-cured bar, kept dry, does not really expire.
What curing actually does
Two different things happen to a new bar of soap, on very different timescales.
First, saponification: lye turns the oils into soap and glycerin. Soapmakers estimate about 99% of it happens in the first 48 hours, with the last traces of lye reacting over the following weeks (Lovely Greens). Our ingredients guide explains the chemistry.
Second, curing, which "is all about water evaporation", creating a harder and longer-lasting bar (Lovin Soap). A home-made bar can lose more than half its water in four to six weeks (Lovely Greens).
Why Aleppo bars take so much longer
Olive-rich soaps are known for needing a long cure. Soapmakers say a 100% olive bar is better given at least six weeks, and that six months to a year is better still (Lovely Greens). Aleppo soap is almost all olive oil, made in large blocks poured on the factory floor and cut into thick cubes, so the water has a long way to travel.
Makers' stated times vary: at least nine months for Najel (Najel) and Alepia (Alepia), and six months to three years across Tadé's range (Tadé). Soapmaker Hassan Harastani has said some bars are aged for up to three years (Reuters via Oman Observer, 2016).
Pro Tip: Weigh a new bar when it arrives and again a few months later. If it keeps getting lighter, it is still drying, which is exactly what you want from a bar you are saving.
A cured bar loses about a third of its weight
Najel says its bars lose around 30% of their weight while drying for at least nine months (Najel). The soap stays; the water goes. That is why a cured Aleppo bar feels heavy for its size and hard as stone, and why it lasts longer in the bathroom than a soft, young bar. See how to use Aleppo soap for keeping it that way.
Why the outside turns gold
During ageing, the outside of the bar turns pale gold while the inside stays green (Wikipedia). The surface is exposed to air for months and oxidises; the core is protected and keeps the colour of the olive and laurel oils (French Soaps UK).
This is one of the easiest ways to tell a traditional bar from a copy: a uniformly green or brightly coloured bar has not been through the same process. Our guide on how to spot fake Aleppo soap has six more checks.
Is older Aleppo soap better?
Older bars are drier and harder, and many sellers prize long-aged soap. Beyond that, we found no published test showing that aged bars clean differently, so we will not claim they are "better" for anything but lasting. The practical difference is simple: a harder bar softens and dissolves more slowly when wet.
| Age of the bar | What is happening | Source |
|---|---|---|
| 0-2 days | Oils and lye turn into soap and glycerin; about 99% done in 48 hours | Lovely Greens |
| 4-6 weeks | A typical home-made bar is cured; it can lose over half its water | Lovely Greens; Lovin Soap |
| 6-9 months | Traditional Aleppo bars dry in open towers | UNESCO |
| 9 months | Najel and Alepia state at least nine months; bars lose about 30% of their weight | Najel; Alepia |
| Up to 3 years | Some makers age bars for years | Reuters; Tadé |
Bars that have done their time. Traditional Aleppo soap in four laurel strengths, cured before it reaches you. See all Aleppo soaps
Does Aleppo soap expire?
Soap remains a good cleanser more or less indefinitely, though its quality declines slowly over time (Countryside). Because it is made from oils, its shelf life is linked to theirs, and soap sealed away from air can turn rancid (Lovely Greens).
In the EU, cosmetic products that keep for 30 months or less must show a "best before" date. Products that keep longer need no date, but show the period after opening for which they can be used, as an open-jar symbol (Regulation 1223/2009, Article 19).
Signs a bar has gone off
The usual warning sign is orange spots, known to soapmakers as "dreaded orange spots". The most common cause is rancid oil; others include old oils, metals in tap water, a high superfat, humidity and contact with rusty surfaces (Soap Queen). A bar with a few spots and a normal smell is generally still usable (Countryside); a strongly rancid smell is a reason to replace it.
Storing and ageing a bar at home
- Keep it airy. Store spare bars unwrapped or in paper, not sealed plastic.
- Keep it dry and dark. A cupboard or drawer away from the shower and direct sunlight.
- Leave space around it. Air on all sides lets the bar keep drying evenly, as the towers in Aleppo do.
Once a bar is in use, the rules change: it needs to dry quickly between washes, ideally on a draining soap dish. Wondering which strength to age? The 10% laurel and 20% laurel bars sit between the extremes.
Pro Tip: Buying several bars at once? Use the oldest first, and leave the newest to keep drying in a drawer. By the time you reach it, it will be even harder.
Frequently asked questions
Why is Aleppo soap dried for months?
Drying allows water to leave the freshly made soap so the bar becomes firmer. Bars are stacked with air gaps rather than packed tightly together. ALEPO’s product pages state nine months of air-drying; traditional production times vary by maker. Soap sold as a finished bar has already been dried—you do not need to wait another nine months after delivery.
Warum ist Aleppo-Seife außen braun und innen grün?
Beim Trocknen und Lagern kann die Oberfläche goldbraun werden, während das weniger der Luft ausgesetzte Innere grünlicher bleibt. Der Farbton hängt von Ölmischung, Charge und Lagerung ab. An der Farbe allein lässt sich der Lorbeeranteil nicht bestimmen.
Kann Aleppo-Seife ablaufen?
Beachte die Haltbarkeits- und Lagerhinweise auf der Verpackung. Bewahre unbenutzte Stücke trocken und luftig auf, geschützt vor starker Wärme und direkter Sonne. Auch Öle können sich mit der Zeit verändern. Bei ungewöhnlich ranzigem Geruch, unerwarteten Flecken oder anderen auffälligen Veränderungen solltest du die Seife nicht weiterverwenden und uns mit Foto und Chargenangabe kontaktieren.
Wie bewahre ich Aleppo-Seife zwischen den Anwendungen auf?
Spüle Seifenreste ab und lege das Stück auf eine Seifenschale mit Wasserablauf, damit es gut trocknen kann. Vermeide stehendes Wasser und direkten Duschstrahl. Gieße angesammeltes Wasser unter der Schale ab. Unbenutzte Stücke lagerst du trocken und luftig. Lass eine benutzte Seife trocknen, bevor du sie in eine Reisedose legst.
The bottom line
The soap in an Aleppo bar forms within days; the six to nine months or more that follow are about drying. That long cure makes the bar hard, dense and slow to dissolve, and it turns the crust gold while the core stays green.
Kept dry and airy, a cured bar keeps for years. For more, read what Aleppo soap is, the history of Aleppo soap, and our guide to the laurel oil percentage.
Stock up and let them age. Single bars from Pure Olive to 40% laurel keep for years when stored dry, and a 6-bar pack is an easy way to stock up. Free EU shipping over €50.
Related reading: the best Aleppo soap brands, Aleppo vs Marseille vs Castile soap and where to buy Aleppo soap.
Sources
- Lovely Greens. "How to cure handmade soap." https://lovelygreens.com/how-to-cure-handmade-soap/
- Lovin Soap. "Saponification versus cure time in soap making." 2016. https://lovinsoap.com/2016/05/saponification-versus-cure-time-in-soap-making/
- Wikipedia. "Aleppo soap." https://en.wikipedia.org/wiki/Aleppo_soap
- UNESCO. "Craftsmanship of Aleppo Ghar soap." 2024. https://ich.unesco.org/en/RL/craftsmanship-of-aleppo-ghar-soap-02132
- Najel. "Fabrication du savon d'Alep Najel." Accessed 4 October 2026. https://najel.net/en/pages/fabrication-du-savon-dalep-najel
- Alepia. "Savon d'Alep authentique 25%." Accessed 4 October 2026. https://alepia.com/fr/authentique-made-in-sy-1/225-savon-dalep-authentique-25-3700479107251.html
- Tadé. "Savon d'Alep" range page. Accessed 4 October 2026. https://www.tade.fr/fr/1007-savon-d-alep
- Reuters, via Oman Observer. "Bombed-out Aleppo soapmaker revives age-old trade." 26 December 2016. https://www.omanobserver.om/ampArticle/91349
- French Soaps UK. "Aleppo soaps." https://www.frenchsoaps.co.uk/pages/aleppo-soaps
- Soap Queen. "Dreaded orange spots." https://www.soapqueen.com/?p=72404
- Countryside. "Does soap go bad?" https://www.iamcountryside.com/soapmaking/does-soap-go-bad/
- European Union. Regulation (EC) No 1223/2009 on cosmetic products, Article 19. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32009R1223
