The control of the Regulating Council of the Guijuelo Mark of Origin begins on the pig farms. The genuine acorn-flavoured Iberian pig is slaughtered after having rooted on the montaneras at will. After the slaughter, during the winter period, the legs of pork initiate a long elaboration process that is controlled by the Technical Services of the Regulating Council. The fruits of the process will only be delivered after at least twenty-four months of patient waiting; ham maintains its properties for well over three years. The industrialists of the Mark of Origin, that have included Pedro Nieto from the beginning, monitor the process with their characteristic traditional virtuosity.

Here hurrying is of no account and time stands still. The artisan plays with the climate of the area so as to control the degrees of temperature. Windows are opened, half-opened, or closed according to the climatic conditions. The industrialists have been able to combine the historic legacy of their ancestors with modern technical innovations, preserving the traditional nature of product elaboration, essential if the differentiating characteristics of their products are to be obtained.

All this determines that the sweet oily fragrance of the Guijuelo hams creates an explosion of delicate aromas on the palate. With its low salt level being one of its most characteristic features, acorn-flavoured Iberian ham with the Guijuelo Mark of Origin shows when cut numerous streaks of fat mixed with the lean meat, with tones varying between purplish-red and pale pink. Its shining golden rind shows the low melting point of acorn fat.

Due to all of the foregoing, ham from acorn-fed pigs does not increase cholesterol levels, and also maintains a very low level of cardiopathies. It can be recognised externally from the form and colour of its fat, from the oiliness of its adipose walls, and from the whitish blue or greyish green mycotic mould next to the V-shaped cut established by the Regulation. its stylised shape and the fineness of its shank finished off by the characteristic black feet, are also characteristic.

Depending on the food given to the pigs during the fattening periods, the legs of ham are classified as follows:

I) Acorn-flavoured Iberian hams. These derive from pigs that have been fattened on montaneras with acorns and grasses from the pastureland ecosystem. This product is identified by a inviolable red seal and a reserva silver band indicating the year. Both the seal and the band are numbered.

II) Iberian hams. These derive from animals that have been fattened on natural fodder controlled by the Regulating Council, as a complement to acorns or exclusively; their genetic purity is always maintained constant. These legs of ham must carry a inviolate green seal as a counter-label and a white band, both of which are numbered.

In both cases the band must be secured with a sanitary tag and accompanied by the manufacturer’s label.

The Technical Services of the Regulating Council carry out an individual classification of the hams protected by this Mark of Origin.