According to the method of raising and feeding the pigs, three qualities are obtained in the well differentiated products:
The Iberian pigs have been bred in pasture in semi-freedom, grazing in the fields and exercising like a wild animal.
In the montanera season, from October to February, the groves of the dehesas, among which include the oaks and the arconoques give their fruits, the acorns, with which the pigs feed with great pleasure.
The acorns are a highly energetic fruit and contain oleic acid in abundance (same component as olive oil). With this feeding of the animals the best hams are obtained that in addition to being exquisite are more healthy.
The animals are raised in semi-freedom in the field, where they graze and live in the field exercising and feeding naturally and cereal feed. Also that there is not eaten in the fattening enough acorn or dehesas without access to the montanera. Normally they are of exploitations that do not have the sufficient number of trees for the amount of pigs that they raise or for a bad harvest of acorns.
Bait field products are minority in the sector and difficult to find.
The normal thing is to breed in dehesa and adjusting the number of heads to the farm to obtain the acorn grade.
The pigs are Iberian bred in semi-extensive, but have not enjoyed the montanera. And they are raised and fattened by feeding them with cereal-based feed (wheat, corn …).