When you think of soft cheeses like Camembert and Brie, a few things come to mind—rich, creamy texture; mild, earthy flavour; and that distinctive white, velvety rind. What many people don’t realise is that a remarkable microorganism, Penicillium camemberti, is behind these characteristics. This little fungus is the key player in making some of the world’s most famous soft cheeses.
SEE ALSO: How to tell good mould from bad mould on your favourite cheese →
In this post, we’ll explore what P. camemberti is, how it works, and its broader role in cheesemaking.
What is Penicillium camemberti?
Penicillium camemberti is a species of fungus, a type of mould, used to produce soft cheeses like Camembert, Brie and Coulommiers. It belongs to the Penicillium genus, which includes both beneficial and harmful moulds found in food production.
This particular species is responsible for the fluffy, white rind that forms on these cheeses. It doesn’t just add texture, though. P. camemberti also helps break down the cheese from the outside, creating that soft, creamy interior we associate with these varieties.
How does P. camemberti work?
Cheesemaking begins with coagulating milk using rennet and acid to form curds. After the whey is drained, the curds are shaped into wheels or blocks, ready for ageing. This is where P. camemberti comes into action.
During the ageing process, the cheese surface is treated with the mould, either by spraying or dipping. The fungus then grows on the cheese, forming a white rind. But P. camemberti isn’t just a decoration. It releases enzymes that break down the cheese’s proteins and fats, transforming its texture and flavour.
The enzymes that break down proteins, a process called proteolysis, soften the cheese from the outer layer inwards. The breakdown of fats, known as lipolysis, releases fatty acids, which contribute to the cheese’s flavour. Over time, this creates the creamy texture we love.
How P. camemberti creates flavour
The breakdown of fats and proteins is essential for developing the cheese’s signature taste. The compounds produced during this process give these soft cheeses their buttery, slightly tangy and mushroom-like flavours.
While the rind itself has a mild taste, the enzymes it releases significantly impact the cheese beneath. As the mould grows, it also produces ammonia, which gives that familiar earthy or mushroomy smell when you open a wheel of Camembert or Brie.
The science behind the rind
P. camemberti creates a soft, velvety rind made of mycelium, the fungal structure. Mycelium is a network of thread-like strands that spread across the cheese surface, forming the smooth white rind.
Under this layer, the cheese undergoes big changes. The mould’s enzymes penetrate the cheese, breaking down complex molecules. This process causes the transition from a firm core to a creamy, runny texture near the rind.
The rind also acts as a barrier, protecting the cheese from harmful bacteria and other moulds while still allowing it to “breathe”.
The history of Penicillium camemberti in cheesemaking
The origins of P. camemberti are closely tied to the history of Camembert and Brie. These cheeses have been made in France for centuries, especially in Normandy and Île-de-France.
According to legend, P. camemberti was first used in the 18th century by a French farmer, Marie Harel. She is said to have created the first Camembert using a local mould. The story goes that a priest, fleeing the French Revolution, taught her how to make Brie. She adapted the recipe, and the mould became known as Penicillium camemberti.
While the story may not be entirely true, what’s clear is that P. camemberti has been used in cheesemaking for generations. In the early 20th century, scientists isolated the specific strain now used to ensure consistent production of Camembert and Brie.
Industrial production of Penicillium camemberti
Today, the use of P. camemberti is carefully controlled to ensure cheese quality. Commercial producers use specific strains of the mould to guarantee the right texture, flavour and rind.
Choosing the right strain is crucial. Different strains of P. camemberti produce different results in terms of taste, texture and ripening speed. Some may create a thicker rind, while others promote a creamier interior.
In industrial settings, P. camemberti is grown under controlled conditions to ensure purity and avoid contamination. This ensures the cheese ripens as expected, without interference from unwanted bacteria or moulds.
The role of P. camemberti in surface-ripened cheeses
The ripening of soft cheeses like Camembert and Brie depends heavily on P. camemberti. These cheeses typically ripen from the outside in, thanks to the enzymes the mould produces. Ripening can take two to six weeks, depending on the strain used, temperature and humidity.
As the cheese ripens, its pH level rises due to ammonia production, making the environment more alkaline. This pH shift helps break down the cheese’s proteins and fats, making it softer and creamier. Flavours also become more intense as the ripening progresses, and the cheese becomes runnier.
Challenges in cheesemaking with Penicillium camemberti
While P. camemberti is essential in making Camembert and Brie, it presents some challenges. One of the main issues is controlling how the mould grows. If it grows too quickly, the rind can become too thick, affecting the cheese’s texture and taste. If the mould grows too slowly, the cheese may not ripen properly, resulting in a dry, firm texture.
Balancing the mould’s activity with other microbes in the cheese is also important. The flavour and texture depend on a delicate interaction of microorganisms. If unwanted bacteria or moulds take hold, they can spoil the cheese or create unpleasant flavours.
Temperature and humidity are crucial, too. P. camemberti thrives in cool temperatures (around 10-12°C) and high humidity (85-95%). Maintaining these conditions is essential for the cheese to ripen evenly.
Health considerations
While Penicillium camemberti is safe to eat, people with mould allergies may have reactions when consuming cheeses made with it. Symptoms can include digestive upset, breathing issues or skin reactions.
People with weakened immune systems or certain health conditions should also be cautious with mould-ripened cheeses. Though P. camemberti isn’t harmful, soft cheeses are more prone to contamination by dangerous bacteria like Listeria monocytogenes, which can cause serious illness.
For most people, however, cheeses made with P. camemberti are safe to eat and provide a good source of protein, calcium, and other nutrients.
Varieties of cheese made with Penicillium camemberti
While Camembert and Brie are the best-known examples, other cheeses are also made using P. camemberti. Some examples include:
- Coulommiers: A smaller, thicker version of Brie made in the Coulommiers region of France.
- Neufchâtel: A soft cheese from Normandy, often shaped like a heart, and slightly firmer than Camembert.
- Baron Bigod: A British version of Brie, made with raw milk.
- Cambozola: A German hybrid cheese, blending Brie’s softness with blue cheese, as it also contains Penicillium roqueforti for the blue veining.
The future of Penicillium camemberti in cheesemaking
As cheesemaking evolves, the role of P. camemberti continues to be explored. Researchers are looking at ways to improve the consistency of soft cheeses by optimising strain selection, ripening conditions and the interactions between microbes. Some are even investigating genetic modifications to create new strains with better flavour development or faster ripening.
There is also interest in using P. camemberti in new types of cheese. For example, vegan cheeses are becoming popular, and some producers are experimenting with using P. camemberti to make plant-based versions of Camembert and Brie.
Conclusion
Penicillium camemberti is much more than a simple mould. It’s a key player in creating the creamy, delicious textures and flavours of soft cheeses like Camembert and Brie. Without it, these cheeses wouldn’t exist as we know them.
Understanding the science behind P. camemberti deepens our appreciation for cheesemaking and the skill involved. From its historical origins to its modern-day use, P. camemberti remains essential to soft cheese production. As cheesemaking continues to develop, its role will likely expand even further.
Cheese lover. Scientist. Created a website and a Youtube channel about cheese science because he could not find answers to his questions online.
