Sodium, in the form of common salt, is one of the essential mineral components of a healthy diet, helping the body to perform vital functions.
A balanced diet is rich in minerals and vitamins and many foods are natural sources of sodium. The percentage of salt we consume from different foods depends on our individual eating habits but typically about 20% of the salt we consume comes from foods that naturally contain salt.
For thousands of years, salt has been used to preserve food and to improve taste. It is also used to as a colour controller, binder, texturiser and fermentation control agent.
First and foremost, salt is used as a seasoning to enhance the taste of food. It makes bland foods such as carbohydrates (bread, pasta, etc) palatable and it helps to bring out the natural flavours in other foods.
Salt is an important natural preservative and has been used for centuries to preserve meat, fish, dairy products and many other foods. Long before the invention refrigerators slating, like pickling, was used to keep food safe to eat.
Within foods, salt brine dehydrates bacterial cells, alters osmotic pressure and inhibits the development of bacterial growth – making it take longer for food to spoil.
It inhibits the growth of clostridium botulinum, the bacteria responsible for serious food poisoning – botulism. Salt helps to prolong freshness making food safer for longer.
Even with the development of refrigeration, this is an important aid to food hygiene.
As a binder, salt helps extract the myofibrillar proteins in processed and formed meats binding the meat together and reducing cooking losses. It also increases the solubility of muscle proteins.
In sausage making, stable emulsions are formed when the salt soluble protein solutions coat finely formed globules of fat, providing a binding gel consisting of meat, fat and moisture.
Salt promotes the development of colour in foods such as ham, bacon and hotdogs. Used with sugar and nitrate or nitrite, salt produces a colour in processed meats which consumers like to see.
Salt enhances the golden colour in bread crust by reducing sugar destruction in the dough and increasing caramelisation.
As a texture aid, salt strengthens gluten in bread dough, providing uniform grain, texture and dough strength, allowing the dough to expand without tearing.
It improves the tenderness of cured meats such as ham by promoting the binding of moisture by protein. It also gives a smooth, firm texture to processed meats. Salt develops the characteristic rind hardness and helps produced the even consistency in cheese.
In baked products, salt controls fermentation by retarding the growth of bacteria, yeast and moulds, preventing wild fermentation. This is important in making a uniform product and reducing the opportunity for harmful bacteria.
Within cheese, salt helps to assure the dominance of the desired flora, controls the rate of lactic acid fermentation, aiding the development of flavouring, body and texture. In cheeses like stilton, for example, this is largely responsible for the taste and texture.