Aged

What is Aged Cheese?

Ripening, also called maturation or affinage, once happened in cellars and caves. A few cheeses still work that way: Roquefort has to be ripened in designated caves in south-western France. Refrigeration arrived in the 20th century and changed the practice, making it faster, cheaper and more consistent.

The work is done by rennet or a rennet substitute, starter and non-starter bacteria, milk enzymes, and in many cheeses added moulds or yeasts. Those agents drive three reactions: glycolysis, proteolysis and lipolysis. The cheesemaker moves the cheese through maturation stages with temperature and humidity held under control. Mould-ripened cheeses are done in weeks because the fungi are more biochemically active than starter bacteria, while hard cheeses take months or years. Camembert-style cheeses need gentle handling of the curd, draining overnight by gravity before brining in saturated salt solution, since the salt level controls how fast proteolysis runs. White-mould spores go on as a spray or a spore bath if they were not added to the milk.

Ripening shows up in the look of the cheese. Bacterial surface growths bring colour, and Brevibacterium linens leaves an orange coat. The round holes in Swiss-type cheese such as Emmentaler, and in some Dutch-type cheeses, are called eyes: carbon dioxide bubbles from propionibacteria in the Swiss types, and from citrate-positive lactococci in the Dutch ones. Yeasts on the surface of cheeses like Saint-Nectaire add flavour and affect the coat.

Taste depends on casein, fat, brine and other elements, many of them specific to the variety. Brine mixes with saliva, carries flavour to the taste buds and sets how moist the cheese seems. Emmental holds more proline than any other cheese, which is why it tastes sweeter. Skip ripening and the cheese has no taste at all. Since the 1970s, chemical analysis of cheese flavour has allowed enzyme-modified cheese, a flavouring made in a fraction of the time with exaggerated cheese notes.