Cheese ripening is a complex process involving many physicochemical changes. Ripening can be divided into two phases; primary and secondary changes, which result in the accumulation of lactic acid, fatty acids and free amino acids. Secondary changes, especially, are catalyzed by enzymes, primarily from microorganisms, that result in the formation of end products typical for each particular cheese variety or batch within a variety.
These chemical and physical changes cause the body of the freshly made cheese to lose its firm, tough, curdy texture and to become soft and mellow. This is related mainly to the progressive breakdown of the protein to smaller polypeptides and gradual accumulation of free amino acids. Parmesan cheese, one of the world’s popular hard type cheese, is also renowned by high content of free glutamate: 1.2～1.6g/100g. The score is nearly equal to kombu which is popular for dashi, Japanese soup stock.Besides Parmesan cheese, there are a lot of glutamate-rich chesses such as Emmental cheese in Switzerland and Cabrales cheese in Spain. Please check graphs where scores of specific free-amino acids are represented.
The graph below shows free amino acids in three kinds of cheese which impart umami. It shows it contains a big amount of glutamate.
（Italy, hard type）
Free Amino Acids in Parmigiano Regianno
Emmental Cheese（Switzerland, hard type）
Free Amino Acids in Emmental Cheese
Cabrales Cheese（Spain, semi-hard type）
Free Amino Acids in Cabrales Cheese