Salt in Cheese: Physical, Chemical and Biological Aspects

Abstract

The use of salt (NaCl) as a food preservative dates from pre-historic times and, together with fermentation and dehydration (air/sun), is one of the classical methods of food preservation. So useful and widespread was the use of salt as a food preservative in Classical and Medieval times that it was a major item of trade and was used as a form of currency in exchange for goods and labour. It is perhaps a little surprising that Man discovered the application of salt in food preservation so early in civilization since, in contrast to fermentation and dehydration, salting is not a ‘natural event’ in foods but requires a conscious act. It is interesting that the three classical methods of food preservation, i.e. fermentation, dehydration and salting, are all exploited in cheese manufacture and in fact are interdependent. The fourth common method of food preservation, i.e. use of high and/or low temperatures, was less widespread than the others because the exploitation of low temperatures was confined to relatively few areas until the development of mechanical refrigeration about 1870 and, although heating was probably used to extend the shelf-life of foods throughout civilization, its controlled use dates from the work of Nicolas Appert (1794) and Louis Pasteur (c.1840). In modern cheese technology, temperature control complements the other three methods of food preservation.