Characteristics of Mantequilla de Soria
The characteristics of butter from Soria are linked to the fact that it is made from the milk of cows whose food comes from an area with a high average altitude (1.026 meters above sea level). Soria is thus one of the provinces with the highest average altitudes and most rugged terrains in the Iberian tableland. This, together with the extremely harsh weather conditions, produces a distinctive livestock diet: the toughness and dryness of the pasture, alongside the characteristic flora, give the milk specific qualities which are passed on to the butter.
The milk will come from Friesian or Pardo-Alpina breeds of milk cow or cross-breeds between the two.
Historical literary references about the province of Soria mentioned the land and villages which together made up the Valle del Tera, a valley where the dairy herd was concentrated and where the butter was produced. In the past, natural butter was called “manteca” and it was produced by using a “manzadero” (tube of elm or willow wood, where milk was beaten); it is now produced using a non-continuous churning cylinder. Both systems involve the binding together of fat globules. For its part, the syrup of the sweet variety is prepared in accordance with the old recipes, and the product is presented in a way which retains the aesthetic appearance and shapes of the past.
Production of ‘natural’ Mantequilla de Soria
In the milk plant, the milk will undergo heat treatment, followed by centrifugation to skim and clean it.
The cream will be pasteurized and cooled so that it reaches the maturation tank where a mixture of the lactic cultures Lactococcus lactis lactis, L. lactis cremoris and L. lactis lactis diacetylactis will be added. Maturation takes place after commencement of the ripening process. Once the cream reaches the acidity, it will be cooled down to slow the ripening process. From there, the cream will be taken to the churn and churned for two to three hours. The amount placed in the churn will constitute approximately 40 % of the churn’s capacity, in order to promote homogenization. The whey will be removed by gravity, the fat will then be washed twice using drinking water, and there will be a process of draining the whey and churning. The fat will then be kneaded slowly for 60 to 120 minutes in a non-continuous butter churn until the butter is formed. It will be shaped using different nozzles. It will be packaged in the plant itself, in the containers in which it will be marketed.
Production of ‘salted’ Mantequilla de Soria
Production of the salted butter will involve the same steps as for the natural butter, except that, when kneading begins, there is a final addition of up to 2.5 % m/m of salt.
Production of ‘sweet’ Mantequilla de Soria
A water and sucrose mixture will be prepared and boiled until syrup is obtained. It will then be mixed together with ‘natural’ butter by churning, and packed in the plant itself. The packaging will be stiff and open at the top, and the visible surface will be garnished with sweet butter previously coloured with beta-carotene or cochineal extract.