Its name officially appeared in 1277, more precisely in a decision of arbitration for the usufruct of small pastures contended between the communes of Castelmagno and Celle di Macra, to be paid with an annual rent of Castelmagno cheeses. Production is still limited today to the communes of Castelmagno, Pradleves and Monterosso Grana and follows a traditional artisanal process.
Cow’s milk is coagulated, if necessary with the addition of sheep’s or goat’s milk, according to seasonal availability. The curd that is produced after about 40 minutes by the addition of calf rennet is broken up into grains the size of a hazelnut and left to rest under the whey; it is then collected in cloths and hung for almost 24 hours to help drain away the whey. The curd is then cut into pieces, transferred into closed containers where it rests from 1 to 5 days, chopped up again, kneaded again with the addition of salt and put into the cylindrical wooden moulds which will give the cheese its shape. The cheeses are then pressed for 1-3 days under stones or iron weights, then aged in cool and damp natural grottos, from 2 to 5 months. At the start of the ageing, to help the internal growth of the mould which takes place following the second kneading of the curd, some producers perforate the paste with rods, as for Gorgonzola; although Castelmagno is a “blue” cheese, the majority of the cheese produced does not have the characteristic internal marbling.
The rind is thin and reddish-yellow in the fresh product and harder and rougher in the aged cheese. In the first case, the paste is pearly white in colour, crumbly and with a mild and moderately salty flavour; in the second, it takes on an ochre yellow colour with, at times, bluish nuances, a more compact consistency and a sharper and definitely saltier flavour.