What an interesting question! I hadn't come across anything independent, but how about this:
Cabeço das Nogueiras Premium also rated highest of the Portuguese contenders in a recent Spanish competition of international olive oils - they can be found here
and are based in Abrantes.
Oliveira da Serra – Seleção Verde and Gallo – Colheita ao Luar* scored next best in that competition, followed by Oliveira da Serra – Lagar do Marmelo.
(Note - the subtitle, e.g. Seleção Verde, matters as many producers make loads, much of which is mass market. Also, re the *, this one is night harvested, which is a controversial process when done by machine as it leads to the death of vast numbers of birds, so on ethical grounds, I would recommend avoiding it.)
Of course, what you find best will depend on what you want to do with it. Most wine producers (at least in the Alentejo/Ribatejo, but elsewhere too) also make olive oil. There are many single varietals, with their own specific properties. These would all be a waste as a cooking oil, but depending on the delicateness of the dish, would be good for dressing, or for dipping (but don't add balsamic if you're using premium EVOO, as I am sure you know!)
In terms of pricing, Cabeço das Nogueiras Premium should be no more than €9-10 per 500ml, Oliveira da Serra – Seleção Verde is €5-6 for 750ml (but as it's a big producer, you can find it for as little as €4 in promotions). €20 per litre is really the most you should ever need to pay for a top end EVOO, and €4-5 max for an everyday EVOO. Beware cynical overpricing in shops aimed at tourists!
If you're after versatile cooking and dressing olive oil, traditional sellers in mercados municipais will sell 5 litre bottles for €20-25 - this is now pretty much all we buy, as it is wonderful in almost every context. However, the relatively flimsy bottles won't ship well. Every now and then, if we're at a vineyard, we get a small, special bottle for dipping.
Oliveira da Serra, in Ferreira do Alentejo, has a whole vineyard-type experience for Olive Oil. https://www.oliveiradaserra.pt/en/ If you head that way, and want a nice overnight stay, consider http://casadoinfante.pt/ which is in Ferreira, and is friendly and well-priced. Nearby is Herdade do Rocim, an excellent wine producer which also makes great olive oil. Their tour and tasting is one of the best we've done. https://rocim.pt/en/ We just did all these bits on a long weekend this month!
Have a wonderful trip in October - perfect month to visit! If you're heading in the Ribatejo direction, feel free to connect for more info!
Discover the beautiful Ribatejo!
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