ADDITIVE MIXTURE TO RUB ABOUT 125 KILOS OF HAMS
Prosciutto Additive Mixture: 1Kg.
Hams which are intended to go through the salting process should be cooled for 24 hours until reaching a temperature of 0°C. This allows the meat to harden becoming easy to cut. Hams should be spread on trays or hung inside the storage in order to get cooled, but never stacked so as avoid bad odor in the bone. Manufacturers generally prefer legs not to be frozen for prosciutto.
They are sorted by weight and a batch and lot number are set for each ham which will remain throughout the production process. Avoid hams from being stained or smelly by breaking the juncture between the femur and the tibia and by removing all the blood from the paw vein. Cut the ham removing part of the fat and hide so that it takes a round shape. This process is also done for a technical reason as it favors salting.
Then, the ham is rubbed with the salt preparation and placed with the hide down in steel tubs or in piles of several layers covering them with salt. There has to be enough salt so that hams are not in contact with each other. Ideally, the salt should be rubbed in a diversified way, the parts of the hide are treated with moistened salt while the lean parts are spread with dry salt. This is an extremely delicate process since it must be performed on legs at a right and uniform temperature. A very cold leg absorbs little salt and one not cold enough can suffer deterioration.
After a week resting period, the legs are washed and then massaged manually from the paw forwards facilitating the drainage of liquid. Finally, they get a second thin coating of salt which is left on another 15 to 18 days depending on weight. It is advisable to turn the hams occasionally in this process, i.e. the ones that were on top in the pile end up at the bottom. In this stage the temperature should oscillate between 1° and 4°C, with approximately 80% humidity.
There are different ways to calculate the salting period. One of them is at the rate of two days per kilo of product, so a 12 kg ham will remain 24 days in salt, in this case the ham must be completely covered. There are manufacturers that leave it in salt for a longer time as in the process described in the previous paragraph; in this case the amount of salt is less. Each manufacturer will decide the dosage of salt and the resting time, it will depend on whether he desires a sweeter or saltier flavor.
The hams are washed with pressurized water or with a brush and are left to soak with running water for about twelve hours. After washing the hams, they are placed on drying rails and then taken to rooms for the initial curing. Now the hams are hung on frames in well ventilated rooms with large windows that are opened when the outside temperature and humidity are favorable; this allows for a constant and gradual drying of the hams. The hams remain there between 30 and 60 days with a temperature between 10° to 15°C with a humidity of 75%. After this resting period, the hams are washed with warm water and brushed to remove excess salt and impurities.
The last step is the Final Curing in which they will remain hung as in the previous process for 4 to 6 months as desired. With a temperature that oscillates between 15° and 18°C.
The prosciutto is finally deemed ready when undergoes rancidity tests by inserting a horse-bone needle into the meat. This bone has the particularity of absorbing the aroma of the meat and then losing it quickly. The horse-bone needle is inserted in five points of the joint and the bone is then smelled by experts for uniformity of aroma and maturation. The smell is easily detectable when the ham is in bad condition and this is the only way to detect it since it is not possible to distinguish a good ham from a bad one. To clean the horse bone, it is stuck in the fat of the ham.
In the last stage of drying when the meat begins to separate from the bone, the exposed surfaces of the hams are softened with a paste of minced lard and salt in order to prevent the external layers drying too rapidly. This is a mixture of pork fat with some salt and ground pepper, and sometimes rice flour. This mixture should be avoided in the lean part near the bacon, where there is a higher humidity and in which the exudate fat itself acts as a protection.