Mills in Alto Aragón - harinero, aceitero, central eléctrica


Centenera is easily reached from Graus. Leave Graus in northern direction towards Campo and Castejón de Sos. Turn right for La Puebla de Fantova. Once there do not enter the village, but continue straight-on towards Centenera and Abenozas. The construction is next to the road just before you cross the Barranco de la Ribera (or de Pinares). Our latest visit was on invitation of the owners who did quite a good job in removing the luxuriant vegetation, making it a much easier job for us than in 1998.

Pictures: I.1998, 08.III.2004

(2) Aceitero left - Harinero and powerstation right.
(12) Slots (algorínes) for fresh olives.

The aceitero is installed in the left (2) part of the construction. The entrance (left most on the picture) is situated away from the road. When you enter you first come into a short gangway leading to a small room lined with what I think were fodder-troughs. It's a feature that we've seen before. The ruello to crush the olives was turned around by a mule and this was the place where the animal could take a quick snack. But as this mill was highly motorized, the trough probably wasn't in use anymore.


(13) Equipment of the oil mill.
Then you'll step into the main room of the oil mill were all activity was centralized. A row of algorínes (containers to stock the fresh olives waiting to be processed) is situated at your left hand against the road-side wall (12). The bricks betray some more recent repairs.

All the equipment is placed in a line against the opposite wall (13). In the corner in the depth is the roller crusher (14) (ruello) resting in its balsa. We have seen a similar contraption in the oil mill of Troncedo where we have also explained how it works. The cog wheels there are absent though, because the system in Troncedo was driven by energía de sangre (a mule as we call it).

The press is of a very modern make. The oldest type of press is of the cantilever type and asks for a long room and a high roof (e.g. Castilsabás, Trillo, Fumanal and Coscojuela). Other sites (e.g. Troncedo and Almazorre) feature a space saving device which is still based on a screw to force a plate down onto the heap of mats with olive-mash.

Our system here is a hydraulic press. The system consists of two separate devices : the press proper (foreground in 13) and a pump (15, 16) to build up the pressure. The bottom plate (19) of the press is mounted on a hydraulic lift. This plate is pumped upwards to squeeze the olive oil out.
The miller could choose between two gears and also between manual or motorized operation. Look at the pictures (15 - 17) to appreciate the switching handle, the ratios between the wheels and the excentric sheave needed to create the up-and-down pumping movement. Oil was forced from the box forming the foot of the pump to the lift under the press through a system of tubes.

(14) Ruello to crush the olives.
(15) Hydraulic pump.
(16) Gearbox of the pump.

(17) Pinions of the roller crusher.
(18) Label on the press.

The tubes form a circuit. A tap in the return tube made it possible to lift the pressure by allowing the oil to flow back to the reservoir.

A similar, and more complete, system is on display at one of the plazas in Castillazuelo, a village in the Somontano de Barbastro region. It is another brand though.

I couldn't find a label on the pump, but the press features one. It says:

La Industrial Mecánica
Cené, Carnicé Y Ca


The fresh olive oil was captured in a gutter leading towards four reservoirs (19 - 21) necessarily below floor level. A rectangular part of the floor is digged out and provided with some stairs to provide a more convenient access to this vessels (pilas).

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