Well, if you thought it was salt, you’d be wrong! We do know what causes the crystalline white deposits found within hard cheeses. It isn’t common salt, and in fact you could say that what the crystals are really made of is not too exciting, but it is of interest to those who have an enquiring mind! The majority of what we find nowadays as crystals in hard cheese is amino acids (most commonly Tyrosine and sometimes Leucine) that have come about from protein breakdown. Protein is naturally found in the milk (and, therefore, the cheese). This protein is slowly broken down as the cheese ages, and in some cases it breaks down to form the aforementioned specific amino acids, Tyrosine and Leucine. Believe it or not, these amino acids move about slowly within the paste of cheese and when enough of them bump into each other, which happens occasionally, and only occasionally, they will join together. This causes a tiny crystal to start (the ‘nucleation site’) and slowly more amino acids join in, so the crystal grows. Although not contributing to flavour these amino acids do contribute to texture, giving hard cheeses a pleasant ‘crunch’. The reason they are…