The biochemical pathways through which flavor compounds develop in cheese during ripening are conventionally grouped into 3 major pathways: (i) proteolysis and amino acid catabolism, (ii) lipolysis and fatty acid metabolism and (iii) the metabolism of lactose and of lactate and citrate. Considerable work has been done in University College Cork over recent decades, together with our colleagues in Teagasc Moorepark and elsewhere, into pathways of proteolysis including study of the role of indigenous enzymes, effect of novel coagulants and identification of the many peptides that are produced from the caseins during ripening. More recently, the effect of oxidation-reduction potential on cheese ripening has also been studied and shown to influence the production of certain volatile flavor compounds. The ripening of hard cheeses such as Cheddar is a slow and expensive process and so its acceleration has attracted considerable work in recent years. Many approaches to accelerated ripening have been investigated, but elevated temperatures have been shown to be the simplest and most effective. Seminal work done in Cork in the 1950s and 1960s into the milk salts system has been extrapolated to cheese in more recent years when it was discovered that the softening of Cheddar cheese early in ripening was correlated closely to the equilibrium between soluble and casein-bound calcium, which corresponds to the equilibrium that exists between soluble and colloidal calcium in milk. Further research has indicated that it is possible to modify cheese texture by controlling this equilibrium. Recent work on the functionality of low-fat cheese has concentrated on the use of hydrocolloids to improve its texture. Translucency is functional property of low-fat cheese that has also been studied in some depth. Factors that affect this parameter include temperature, levels of total and insoluble calcium, TiO₂, homogenization and addition of annatto. This presentation will provide an overview of the results of our work on the ripening of Cheddar cheese.