Penicillium camemberti

What the mould is

Penicillium camemberti is the white mould that covers Camembert and related soft cheeses. It forms a dense, white, fluffy coat on the rind, and its growth is what makes the cheese's surface and its interior texture change during ripening.

It is a cultivated fungus rather than one found only in the wild. Genomic work places it as a distinct cluster, closely related to the blue-green P. biforme, and the two are treated as products of separate domestication steps.

How it came to be on cheese

Ropars and colleagues describe the domestication in stages. The first event produced P. biforme, which is used in some fresh goat cheeses. A later, more recent event produced the white P. camemberti that is used for Camembert.

The domesticated species differs from wild relatives in traits that suit cheese ripening: it grows faster in the cool, humid conditions of a ripening cellar, is whiter, and produces no toxin or only very small amounts of a potentially dangerous one. It also suppresses undesirable moulds on the cheese.

Varieties and naming

The bioRxiv preprint of the same work is titled as a diversification of P. camemberti into two varieties. The CNRS page read here does not name those varieties, so this page does not describe them in detail. Mould catalogues list older names for the organism, including P. candidum, which should be checked against a taxonomic database before use.

Notes

The source read for this page is a research summary, and the genome figures and horizontal gene transfer points reported in secondary coverage were not checked against the primary paper. Strain identity matters: a species name does not establish which culture a cheesemaker uses.