Castelo de Marvão Olive Oil Press and Museum


Did you know that most of the olive oil available today has not been pressed, but extracted using chemical solvents? That you can call an oil ‘extra virgin’ just by adding some acidity? That cigarette lighters used to be smuggled over the border from Spain to Portugal because you needed a licence to own one?!?

These are just some of the things we learnt from a couple of hour’s company with Antonio at the Galegos Lugar Museu in the Alentejo. After a few solid months of vineyard visits, we decided that it might be nice to shift our focus to olive oil – for a couple of hours, at least. It struck me that olive oil is similar to wine in that many people in the UK consume it regularly, but I imagine most, including myself, don’t know much about it.

A bit of history

Galegos (a couple of hours drive inland from Lisbon) is a quiet village, the very last Portuguese village before you cross the border to Spain, where we’re spending a month in a former smuggler’s headquarters – the border-markers literally run round the outside of the house. When we take our morning coffee from the kitchen out to the garden, we drink it in not only a different country, but also a different time zone. Our mobile phones are constantly confusing us by arbitrarily switching time zones, and we get ‘Welcome to Spain’ and ‘Welcome to Portugal’ texts numerous times a day.

Galegos was once quite the exciting place to live, it seems. Antonio, the owner of the olive oil press and museum, tells us how ’there used to be two types of people living here: smugglers; and the police trying to stop them.’ Antonio’s grandfather, also named Antonio, was one of the former. And as if that wasn’t exciting enough a backstory, there’s romance too: the press was built here in 1952, after Antonio senior met his future wife, Carmelin, a rich young lady from Madrid, in the nearby Spanish town of Valencia de Alcantara. Realising that the smuggler’s lifestyle didn’t give him much to offer in the way of financial security, he decided to set up an olive oil press in the village – oil, along with coffee and wine, was one of the major commodities smuggled over the border from Portugal to Spain, because it was useful not just for food, but also for fuel, light, and other essentials. At that time, Antonio tells us, the price of ten litres of olive oil equated to one week’s salary. So, in the last village before Spain, there was an understandable demand for being able to press your olives.


The cold press method

The lagar (press) museum here opened earlier this year, part of a project that began in 2010 when Antonio, previously an architect in Lisbon, decided to return to his roots in the Alentejo countryside and revive his grandfather’s olive oil press, investing in cutting-edge technology to ensure the highest quality oil, about which he is clearly passionate. This allowed both a development of his own brand of oil, Castelo de Marvão, and an option for locals to press and bottle their own olives. Antonio has kept the old press, however, which now forms the museum part of the operation, and it’s well worth seeing.

The original press was set up to run what is known as the ‘cold press’ method – still the traditional method capable of producing the highest quality oil, as other methods that involve too much heating, though achieving higher yields, can damage the fruit and the subsequent oil quality. The cold press retains much of the flavour and nutritional value of the oil and reduces taint from the skin and the stone of the olive.


The method works by running olives down a hopper to be crushed on a rotating table by three huge stone ‘wheels’, forming a paste which is spread onto circular mats. These are then stacked onto a large spindle, which, when full, is rolled over to the press which crushes the mats together and extracts the oil.


This seems a simple process, but among other things, the press was originally hampered by the fact that there was no electricity in the village, not to mention that suitable engines were expensive and had to be imported from Germany. The solution to the first problem was solved by turning the local watermill into an electricity generator (forget making bread!). The press got its power source and Carmelin became the only lady in the village with electricity. And with only the funds to buy one engine for his press, it had to run every single part of the process – the solution is amazing to see, with just one small engine powering wheels and straps of various lengths and sizes, as well as a host of pulleys, levers, presses, train tracks and of course the formidable stone rollers, resulting in what looks like a very big game of Mousetrap. The press was run like this until 1999, when competition from much cheaper olive oils (about which more below) obtained from more mechanised processes unfortunately led to its closure.



The reason the olives here are so good is that the surrounding area is rich with old ‘galega’ olive trees – brought in by the Romans, who prized their flavour – which in many other areas were pulled up and replaced by higher-yielding varieties. Thankfully, the slow pace of life here meant that this rarely happened and, though the olives themselves are small and yield only 3-4% oil in terms of the total mass of each olive, the flavour is distinctive in that it gives a sensation of sweetness, as well as remaining stable for up to two years after pressing, when many oils only retain their quality for half that time.

Another bonus when it comes to quality is that the galega trees can’t be harvested using mechanical methods (or just putting a net under it and whacking the tree with a stick, which apparently is another way to do it!) – instead you put protective gloves on and ‘rake’ the branches with your fingers gently, meaning the berries are not damaged and only those that are ready to come off will do. In a similar way to wine, recent developments in technology and demand have led to mechanised harvesting techniques and thus cheaper oils. Not a bad thing itself, until it becomes so much the norm that the demand for the higher quality stuff is eclipsed to the point that many people don’t even know it’s out there. In fact, Antonio tells us that many people who visit from all across the world, and take home the free bottle of oil per person included in the entrance price, get in touch again to have Castelo de Marvão oil shipped over to them, as they are unsure how or where else to get hold of real oil of this quality.


So what about the oil I normally buy?

The most widely-used method for extracting oil is, unsurprisingly, the most efficient. Using hexane, a chemical solvent, and a process involving high heat, it’s possible to extract more than 99% of oil from the olive, whilst traditional pressing methods can leave up to 14% of the oil behind. Obviously, this leads to much cheaper oils than can be obtained with traditional methods, and has had the knock-on effect of presses like the original one in Galegos going out of business, not able to compete with the sort of prices people have become accustomed to.

As with many of these things, though, there is a ‘hidden cost’: apart from the serious matter that the solvent method leaves traces of hexane, which is a highly toxic carcinogen, the heat required is damaging to both the nutritional value and the flavour of the oil, losing volatile aromas and leaving it much more unstable.

Is it easy to tell the difference? It is when you have the oil in front of you, and particularly if you have some pressed oil to compare it to. Whereas an industrially-produced wine still has obvious aromas, in fact has been engineered to have bold, attractive, fruity aromas, an olive oil extracted using industrial methods smells positively dead compared to one traditionally-pressed. Apparently, many older customers of Antonio’s have happily told him their oil now reminds them of the flavours of their youth! The problem with a taste comparison is that, usually, by the time you’re tasting it, you’ve already bought it. There is no legal requirement to mark how the olive oil has been extracted, or that it includes hexane, so just reading the label won’t help you know in advance of purchase. Even the term ‘Extra Virgin’ (which is an expression of the level of acidity, based on the fact that early-pressed oil is subject to less oxidation and therefore lower acid levels) can be achieved by a chemically-extracted oil through manipulations. The best you can do is look for labels which specifically denote that the oil has not been extracted chemically: terms such as ‘unrefined’, ‘cold-pressed’ or ‘organic’.

How is the oil pressed in Galegos now?

When reviving the press, Antonio decided to invest in new technology, as, despite the fact that the cold press can produce quality oil, it requires a lot of manual labour, and the length of the process means that the olives are exposed to oxygen for long periods – olives start degrading through oxidation the moment they are picked, and should be pressed within 24 hours of picking.


Since the foundation of the Galegos lagar, an extraction method called decanter centrifugation has been invented, which Antonio has put in place. It consists of three machines – one to break open the olives, one to mix in warm water to form a paste (the water is heated by burning the discarded olive stones, and is kept at a low temperature), and the third, the centrifuge, spins and separates the oil from the paste. The method allows for a high level of extraction, less labour, and the all-important retention of flavour compounds and nutritional value. It’s also a much quicker, continuous process, which helps when it comes to pressing olives for locals – which makes up 80% of Antonio’s business, he tells us. It’s often a social affair, apparently – if you’d like your olives pressed, you’re allocated a slot, so you know the optimum time to pick. Many people invite family and friends round to help with the harvest and the transportation, then, a matter of hours later, a nifty trick involving your tank and a QR code means that you’re sent a text when your oil is ready to be bottled, at which point you all crowd round the tanks and get it done as quickly as possible, as the next person in line needs their olives pressed asap!

How to taste olive oil

We finished the visit with a tasting, of course, and compared various oils (as well as getting through a whole bottle of wine whilst we were tasting and chatting, the excuse being that wine and oil goes together so well!). Antonio showed us how to pour a little of the oil into a glass and cover it with one hand whilst warming the oil by cupping the glass with the other. The aromas and flavours show better closer to body temperature. Once the oil had warmed a little, we uncovered the glass and stuck our noses in, and it really was incredible how much life the real quality oils had, as well as how distinctive they were.


I’d thoroughly recommend a visit to both the beautiful area around Galegos, and booking a tour with Antonio – he’s unmistakably passionate about what he does, and we felt very privileged to have spent a couple of hours sharing in his knowledge and love for good olive oil.

The lagar museum’s website is at


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