If a time machine could take us back to Ancient Rome, we might find ourselves side by side with the artisans of the period, all intent on stuffing large fish into terracotta urns, in between generous layers of salt. Salting, as it is called, is a technique for preserving food that lives on and is still carried out using the same methods and processes. For the reasons we are about to discover, salt is actually able to preserve most foodstuffs for months and even years. At the same time, this method of preservation confers a unique and delicious flavour to food whose refinement derives from its high degree of salinity. What more can be said about an exquisite plate of herrings? And the tasty capers used to flavour a dish of pasta in tomato sauce? These are just two examples of how important salting is and why it is worth while finding out the secrets behind it.
Let’s start from basics: why does salt act as a preserve? To understand this concept, let’s consider a piece of meat placed in a terrine and covered with cooking salt. After a few minutes, we see the salt crystals “disappear”. In actual fact, they do not disappear: they simply absorb water to the point that they melt completely. No magic is involved here: it is a physical-chemical phenomenon called “osmosis” whereby two solutions, which are brought into contact with each other, achieve the same degree of saline concentration and in order to reach a situation of equalization, the water molecules in the meat simply relocate to our dear old salt grains. To simplify, we could say that the salt absorbs the water in the meat but, if you have a scientist friend, you can impress him by proving that you understand how osmosis works. Usually, however, a salt and water solution is used rather than salt alone: in this way we are sure that osmosis takes place over the entire surface of the meat.
Why is it so important for this to happen? Because, as you have already grasped, the function of osmosis is to dehydrate the meat, or whatever other food we intend to preserve. To dehydrate means to remove water, the most precious element of life, comprising the bacteria responsible for decomposition. Which is the exact phenomenon we wish to prevent! By removing water, we prevent bacteria from making our precious food go rotten! For a correct salting process, whatever raw material is involved, we must follow a few simple rules. First of all, we will use a highly concentrated salt solution. Ideally, we will take the amount of water necessary to completely cover the food and then we will add salt gradually, mixing as we go, until we reach the point where salt starts to deposit on the bottom. This is now a “saturated” solution and therefore perfect for our purpose. Once the food has been immersed in the solution, keep it in the fridge for several days (depending on its type and quantity), closed with a stopper or a hermetic lid.
At the end of this period, change the brine if the food is to be kept in the liquid or dry it and cover with cooking salt. In the case of meat or other protein-rich foods, you may dry it and place it in an oven at a low temperature. For a superior result, a natural drying method is to be preferred: meat and fish lend themselves marvellously to being stored in a dry, well-aired place. When they are well dried out (several weeks are required), they may be enjoyed cut into fine slices and possible served with lightly toasted bread spread with a butter of excellent quality.