Algerian Vats: Why We Vinify in Cement Since 1947
The Algerian vats at Pinhal da Torre, set inside the 1947 winery in Alpiarça, are a rare typology in Portugal. Natural micro-oxygenation, thermal stability and Ducellier architecture shape the profile of our Tejo wines.
Before stainless steel, before electric temperature control, there were engineers who solved the problem of fermenting in hot climates with pure physics. Our Algerian vats are that solution — and they still work every harvest. ## What Algerian vats are Algerian vats are cement fermentation vats of a typology developed in French Algeria in the early 20th century, when the region was one of the world's largest wine producers. The challenge was simple and brutal: ferment large volumes of grapes in hot climates, without reliable electricity and without refrigeration. The answer was engineering — the **Ducellier system**, which used the pressure of fermentation CO₂ itself to perform automatic pump-overs, with no pumps, no motors, no constant human intervention. When the Pinhal da Torre winery was built in **1947**, this typology was the one chosen. Not out of nostalgia — nostalgia did not yet exist, this was cutting-edge technology. Because it worked. Nearly eighty years later, the vats are still in active production. We are today one of the rare wineries in Portugal where this architecture survives intact and in use — not as a museum piece, but as a winemaking tool. > **In short:** the Algerian vats at Pinhal da Torre, in Alpiarça (Tejo DOC), are Ducellier-type cement vats integrated into the winery built in 1947, still in use today — a rarity in Portugal. ## Why cement — not stainless, not wood The industry spent decades treating cement as an outdated material. Vats were ripped out across Europe to install stainless steel. And then, over the past fifteen years, the most demanding producers in the world — from Burgundy to Priorat, from the Rhône to California — started buying cement again. Concrete eggs, restored traditional vats, cement amphorae. What changed? Nothing about cement. What changed was the understanding of what it does. Cement is **neutral but not inert**. Unlike new oak, it lends no aromas — no vanilla, no smoke, no make-up. The wine that comes out is the wine of the grape and the place. But unlike stainless steel, cement is not an airtight safe: it breathes. And that breath is the secret. ## Micro-oxygenation: the slow breath of concrete Cement walls have a minimal natural porosity that allows slow, continuous oxygen exchange — what oenology calls **micro-oxygenation**. Tiny amounts of oxygen come into contact with the wine during fermentation and ageing, and do silent work: they polymerise tannins, linking short, aggressive molecules into long, silky chains. The result in the glass: **polished tannins without resorting to wood**. The effect is comparable to a used barrel — but without the aromatic contribution of oak. That is why wines vinified in cement tend to show round texture and pure fruit at the same time, a combination stainless steel alone cannot deliver and new wood only delivers at the price of toasty aromas. ## Thermal inertia: stability without electricity Fermentation is an exothermic reaction — it produces heat. In stainless steel, that heat dissipates or accumulates quickly, because the metal is thin and thermally reactive. The walls of the Algerian vats, with their concrete thickness, work as a **natural thermal regulator**. They absorb heat slowly and release it slowly. In practice, fermentation runs along a smooth temperature curve, with no peaks or sudden drops. This matters because yeasts hate thermal shocks: sharp variations cause stress, stuck fermentations and loss of aromatic compounds. In a hot region like the Tejo — Quinta de São João sits 56.53 km from the Atlantic, with the moderating influence of the river but demanding summers — this passive stability is a real oenological advantage, not folklore. > *"Cement adds nothing to the wine. And that is precisely why it adds everything: it lets the grape and the place speak without interruption."* > — Mário Andrade, winemaker at Pinhal da Torre ## An architecture you cannot copy Any producer today can order a concrete egg. What you cannot order is a battery of Algerian vats built in 1947, integrated into the structure of the winery building itself. Our vats are not inside the winery — **they are the winery**. The vat walls are walls of the building; the internal geometry, designed for the Ducellier system, is part of the original architecture. This integration has practical consequences: the thermal mass of the building-vats assembly amplifies temperature stability, and the scale of the vats — sized for the viticulture of the time — adapts well to the parcel-by-parcel vinification we practise today across our **30 hectares of estate vineyards**. Eight generations of family production have passed through this winery. The vats have seen every harvest since 1947. ## What it means in the glass When you taste a Pinhal da Torre wine and find clear fruit with silky texture — without the varnish of new oak — you are tasting the work of these vats. Cement vinification is one of the reasons we defend a simple principle: **winemaking should be invisible**. Cement, stainless steel, little new wood — tools that preserve rather than transform. The Algerian vats are the oldest and most radical expression of that philosophy in our winery. ## Frequently asked questions **What are Algerian vats?** Ducellier-type cement fermentation vats developed in French Algeria in the early 20th century for hot climates. They enabled automatic pump-overs powered by fermentation CO₂. At Pinhal da Torre we use them for the fermentation of some of our most iconic wines. **Does cement give flavour to wine?** No. Cement is neutral — it transfers neither aromas nor tannins. It gives texture, through slow micro-oxygenation, and preserves the purity of the fruit. **Cement or stainless steel — which is better?** They are different tools. Stainless preserves maximum aromatic freshness; cement delivers more polished tannins and thermally more stable fermentations. At Pinhal da Torre we use both, depending on the profile of each wine. **What is micro-oxygenation?** The slow exchange of tiny amounts of oxygen through the porosity of cement, which polymerises tannins and makes them rounder — an effect similar to a used barrel, without wood aromas. **Where can Algerian vats be seen in Portugal?** The typology is rare in the country. At Pinhal da Torre, at Quinta de São João in Alpiarça (Tejo DOC), the original 1947 vats are still in production and can be visited by appointment.