The way is long for a plum to become a prune with a fine and tasty pulp, this is why we call the prune d’Agen the “black gold of Aquitaine”
The prune harvest
A good prune is at first a plum collected in full maturity.
The harvest is traditionally made between in the middle of August and in the middle of September. To collect only the most mature fruits will be needed on average 3 for 4 passages on every plot of land. The harvest can be mechanical or manual.
Nowadays, the faster, more productive, mechanical collection is the most wide-spread. However, the manual picking is often used as a supplement to the mechanical harvest. Every tree can produce up to 100 kg of fruits.
It is the operation which consists in dehydrating the plum d’Ente, to transform it into prune. Once collected, the plums d’Ente are transported on the exploitation where they will successively be washed, sorted out and put on sieve by an operation of calibration.
We need between 3 and 3,5 kg of plums d’Ente to obtain, after 20 to 24 hours of drying, 1 kg of prunes of Agen. It is also during this step that we can produce the semi-dried prunes.
Indeed, by reducing the time of drying at 10 or 12 hours, we shall obtain a prune with a 35% humidity, thus a soft prune without rehydration. On the other hand, an immediate bagging and pasteurization will be necessary, because this rate of humidity does not allow a long preservation.