Amidst the holm oak of the Dehesa, a scrubby pasture dotted with trees that runs along the Portuguese border in western Spain, large black pigs snuffle contentedly for fallen acorns. It is here that one of Spain’s greatest and most expensive foodstuffs begins its life: jamón Ibérico de bellota (Iberian acorn ham).
The finest cured legs of these black Iberian pigs can sell for more than £45 per kilo (that’s hundreds of pounds per leg), and they come from these free-range pigs that roam the oak forests eating nothing but acorns. The creatures’ diet and exercise, along with a 36-month curing process, results in exquisite meat.
Spain produces more than 40m hams each year. And almost every restaurant or tapas spot across the country will have a leg standing ready on a special support, waiting to have wafer- thin slivers shaved off it and presented fanned out over a plate. If jamón Ibérico de bellota is the pinnacle of ham production, there are also lesser grades including jamón Ibérico cebo de campo, from pigs that have eaten a combination of acorns and grain, and jamón Ibérico de cebo, from pigs that have only eaten grain, which is around half the price of the bellota.
Unlike the white pigs used to make jamón serrano in eastern Spain, Iberian pigs are fat, black and fairly hairless, with long snouts and slender legs featuring black hooves that have earned them the nickname “pata negra” (“black hoof”).
The production of jamón Ibérico is strictly regulated, with a Designation of Origin (DO) covering everything from the rearing of the piglets to their slaughter and the lengthy curing process that takes place before the jamón is ready to eat. Piglets are fed on a diet of cereals and acorns until they’re about 18 months old. Then for the final three months of their lives they roam the Dehesa, scavenging for acorns. This period is known as the montanera, when the acorns fall from the trees between the beginning of October and the beginning of January. Only pigs that reach at least 160kg can qualify to become the prized jamón Ibérico de bellota, and to ensure they get enough to eat, the DO regulations specify that there can be no more than two pigs per hectare to hoover up around 7kg of those precious bellota every day.
It is in the all-important acorns that the secret of jamón Ibérico’s magical flavour lies. Acorns from the holm oak are rich in oleic acid, the same fatty acid found in olives. In fact locals often refer to the rotund black Iberian pigs as ‘olives on legs’, and it's not hard to see why. Once the curing process is complete and the heavy marbling in the meat has broken down through various chemical processes and the saturated fats have been transformed into monounsaturated fats, the only food with a higher level of oleic acid is olive oil.
When the time comes for the pigs to go to matanza (slaughter), also known as the “sacrifice” – which tells you everything you need to know about how the Spanish feel about jamón) – they are despatched in a carefully controlled and humane fashion, and both the front legs (paletas) and the rear legs (jamónes) are used for hams. The rest of the pig is not wasted; it becomes a host of tasty pork products from chorizo to cured tenderloin. The curing process is laborious: the legs are chilled and then covered in Andalucían sea salt for several days (usually about a day for every kilo). They’re then washed and hung to dry (for up to three years for the finest jamón). The age of the meat can be clearly seen in the final product: younger hams are lighter pink, older ones a rich ruby red.
It's a long road from pigsty to plate, but as the rich fatty meat dissolves and releases its unique flavour, like a fine wine rolling over the palette, you can taste the essence of Spain, its land and its people. And it tastes good.