French Blue Cheese
Let’s start with the obvious: blue cheese contains mould. Please don’t let that put you off, because this is a “good” mould, chosen and tamed by cheesemakers over centuries, and it’s exactly what gives the cheese its delicious flavour! Once you get past the idea of eating mould, I can promise you’ll find a blue you really enjoy.
Roquefort is the best-known French blue cheese, aged in natural limestone caves in the south of France, but there are plenty of others from the Auvergne, the Jura mountains and the Alps. So if you’ve ever stood in front of a blue at the cheese counter and hesitated, what you were looking at was carefully controlled fermentation rather than food that had gone off.
Table of Contents
What is a French blue cheese?
In French, blue cheeses are called fromages à pâte persillée. Persillé comes from persil, parsley, because the paste looks as if someone had sprinkled it with chopped herbs, and unlike the white mould on a Camembert, these veins grow inside the cheese rather than on the outside.
In everyday French we just say un bleu (meaning a blue), although strictly speaking French dictionaries keep the word bleu for cow’s milk blues, which is why Roquefort, a sheep’s milk cheese, is called a pâte persillée and never a bleu. (Nobody at the cheese counter will correct you if you mix them up though, I promise.)
Why is blue cheese blue?
The colour comes from the mould itself: as Penicillium roqueforti grows through the cheese, it produces blue-green spores, and those are what you see as veins.
The mould needs oxygen to grow, though. The spores are mixed into the milk or the curds right at the start, but they can’t do much while they’re shut inside a dense, airless cheese, so a few days or weeks into its life each blue is pierced with long needles. Every hole works like a little air shaft, and the mould grows along it and out into the cracks between the curds, which is why you can often still see the needle lines when you cut a blue cheese in half.
As for where the mould came from in the first place, legend says a young shepherd in the Aveyron left his bread and cheese in a cave to go after a girl, and came back weeks later to find the cheese streaked with blue. Nobody can prove it, of course, but it’s a good romantic story! What is documented is that cheesemakers in the south traditionally grew their mould on rye bread left in the caves until it turned blue all the way through, then dried it and ground it into powder. Most producers use laboratory cultures today, but a few still bake their own rye loaves to grow it.
Why does blue cheese taste so strong?
Once the mould gets going, it does a lot more than add colour, because it slowly starts breaking the cheese down from the inside.
It produces enzymes that break up the fats (cheesemakers call this lipolysis) and the proteins (proteolysis). The fat breakdown releases the aromatic compounds behind that sharp, peppery, slightly spicy bite you’d recognise with your eyes closed, while the protein breakdown softens the paste and gives it a savoury, almost brothy depth.
Blues are also heavily salted, partly to keep unwanted bacteria away, and the salt is what pulls the tang and the creaminess together. All this means a blue changes a lot as it ages, and the same wheel tasted at one month and again at three can feel like two different cheeses.
Explore the blue cheese collection
This guide covers the basics. For a closer look at individual cheeses, our collection articles each feature five varieties, with tasting notes and where to find them:
The defining characteristics
What makes a blue cheese a blue cheese?
Rind: From almost none (Roquefort, which spends most of its life wrapped in foil) to a thin, dry, natural rind (Fourme d’Ambert, Bleu de Gex).
Aroma: Pronounced and a little pungent: damp cellar, mushroom, sharp dairy. Strong, and nothing like a washed rind cheese.
Texture: Anything from soft and almost spreadable to firm and crumbly, depending on the milk, the cheese and its age.
Flavour: Salty, tangy and peppery, with savoury, buttery or mushroomy notes underneath. Mild and milky in some, powerful and long in others.
Making: Penicillium roqueforti added to the milk or curds, an unpressed paste, and piercing to let air reach the mould.
How French blue cheeses are made
The bones of the process are the same as for most cheeses. The interesting bits are where the mould and the air come in.
1. Milk and mould
It starts with milk, which is cow’s for most French blues, sheep’s for a few and occasionally goat’s. Penicillium roqueforti is added at the start, either into the milk or sprinkled onto the curds.
2. Curdling and cutting
The milk is soured with cultures and set with rennet, then the curd is cut into fairly large pieces, which leave more gaps between them for the blue to grow into later.
3. Moulding without pressing
The curds are ladled into moulds and left to drain under their own weight. Blue cheeses are never pressed, so the paste stays open, with little cracks and pockets for the mould to spread into.
4. Salting
The cheeses are salted, usually by rubbing dry salt over the outside, which draws out moisture, keeps unwanted bacteria in check and seasons the cheese.
5. Piercing
This is the step that sets blue cheese apart from every other family. Each cheese is pierced right through with long stainless steel needles to let oxygen reach the mould inside, and how often and where it’s pierced shapes the veining.
6. Cave or cellar ageing
The cheeses go into a cool, very humid cave or cellar, typically around 10°C (50°F) with humidity of 90% or more, where the mould spreads along the needle holes and through the cracks in the paste.
7. Slowing things down
Once the blue has developed enough, many cheeses are wrapped in foil and moved somewhere colder. The foil cuts off the air, so the mould slows down and the cheese can keep maturing gently without turning too aggressive. For the protected French blues, the minimum ageing runs from about three weeks to three months, depending on the cheese.
Cave aged blue cheese
Plenty of blue cheeses mention a cave on their label, but in France two protected blues have natural caves written into their rules, and the most famous of them is Roquefort.
The caves of Roquefort-sur-Soulzon, a village in the Aveyron in south-west France, sit inside a huge rockfall at the foot of the Combalou plateau, where a section of limestone cliff collapsed long ago. Over the centuries the villagers dug their cellars into this jumble of rock, several storeys deep.
What makes these caves special are the fleurines, natural chimneys running through the fissures in the rock. Air moves through them between the surface and the cellars, keeping the caves cool, damp and gently ventilated all year round, which suits Penicillium roqueforti perfectly. Roquefort isn’t the only one either, as a cow’s milk blue from the neighbouring causses must also begin its ageing in natural caves with their own fleurines.
Most other French blues are aged in cellars rather than natural caves, with the temperature and humidity controlled to copy cave conditions as closely as possible.
The spectrum of French blue cheeses
Even though the technique is much the same, French blues can feel completely different on the board, and the milk, the age and the amount of piercing all play a part.
By milk
Cow’s milk
Most French blues, usually creamier and a little more yellow, from mild and milky to bold and earthy.
Sheep’s milk
Whiter, richer and saltier, with a buttery tang that lingers.
Goat’s milk
Rare, usually small farmhouse cheeses, with a fresh, lightly tangy note under the blue.
By intensity
Mild
Creamy, milky and gentle, with modest veining and only a little peppery bite. These are the blues to offer anyone who’s sure they “don’t like blue cheese”.
Balanced
More character and more blue, but still rounded and creamy, with mushroomy, buttery notes alongside the tang.
Strong
Salty, sharp and long, with plenty of blue running through a firmer or more crumbly paste. The strongest are often the longest-aged.
By region
Auvergne and the Massif Central
A land of volcanic hills and mountain pastures, where the blues are made with cow’s milk and range from very mild to bold and mushroomy.
The Aveyron and the causses
The limestone plateaus of the south, home of the natural caves, where the blues tend to be powerful and salty.
The Jura and the Alps
Mountain pastures and cow’s milk again, with blues that are usually mild and creamy, with a nutty sweetness and fairly light veining.
How to buy French blue cheese
Blue cheeses become a lot less mysterious once you know what to look for, both in the cheese itself and on the label.
What to look for
- The veins: If you can see the cut surface, the blue should look clean and bright, anywhere from blue-green to grey-blue. Some brownish halos around the veins are normal in older cheeses, but dull grey or slimy patches are not.
- The paste: It should be ivory to pale cream (a little more yellow in cow’s milk blues, whiter in sheep’s milk ones), with no pink or orange patches creeping in.
- The feel: If you’re allowed to press gently, a soft, yielding paste means a younger, creamier, milder blue, while a firmer, slightly springy feel suggests a balanced cheese that’s ready to eat. Very firm and crumbly usually means something more intense and salty.
- The smell: It should smell clean, sharp and mushroomy, and a sour or ammonia smell means it’s past its best.
Reading the labels
AOP: This tells you you’re looking at a protected blue, made in its own area under strict rules. It won’t promise you’ll love it, but it does promise you’re getting the real thing.
Fermier or laitier: A fermier (farmhouse) cheese is made on the farm with the farm’s own milk and usually has more personality, whereas laitier means it was made in a dairy with milk collected from several farms. Most of the blues you’ll come across are laitier, so a fermier blue is a nice find.
Lait cru: Raw milk. Raw-milk blues tend to taste more complex than pasteurised ones. Some protected blues must be made with raw milk, while others may be raw or pasteurised depending on the producer. Raw-milk and soft cheeses are generally advised against during pregnancy and for vulnerable people, so check your local health advice.
How to store blue cheese
The fridge is the right place for all blue cheeses, and the vegetable drawer is usually best because it’s slightly more humid than the rest of the fridge, which blues like. Aim for about 3 to 7°C (37 to 45°F).
Blue cheese needs a little air but not too much. Left uncovered, it dries out and cracks and the veins turn dull and brown, while wrapped too tightly it sweats and can grow the wrong kind of mould, so what you’re aiming for is a cheese that’s gently wrapped and loosely contained.
If your cheese came wrapped in foil, you’re already halfway there and can rewrap the cut piece in fresh foil before putting it back. Otherwise, use cheese paper or baking paper (parchment paper), then slip the cheese into a box or a loosely closed bag. Avoid cling film (plastic wrap) pressed onto the surface, as it traps moisture and the cheese turns slimy instead of creamy.
Blues release moisture as they sit, so rewrap them every few days if the paper gets damp. If you keep other cheeses nearby, give the blue its own container too, otherwise the mould may slowly move in on your Comté.
How long does blue cheese keep?
Blue cheese will perfume your fridge, which is perfectly normal, so keep it wrapped and away from mild foods like butter and milk that pick up smells easily.
As a rough guide, creamy blues are happiest eaten within one to two weeks of opening, and firmer, drier blues can last three to four weeks if you keep rewrapping them. Always go by the use-by date on the pack first.
Can you freeze blue cheese?
You can, but it’s only worth doing if you plan to cook with it, because freezing changes the texture and a creamy blue turns grainy and crumbly once thawed. Crumble the cheese, wrap it well and freeze it for up to about three months, then use it straight from frozen in sauces, dressings or gratins. When it’s for a cheese board, buy a fresh piece.
How to serve blue cheese
Temperature makes a huge difference, so take blue cheese out of the fridge 30 to 45 minutes before serving. Straight from the fridge it tastes muted and feels waxy, and it’s only once it softens that all the flavour comes out.
On a cheese board, give the blue its own cheese knife so it doesn’t streak everything else, and put it last if you’re tasting from mild to strong. Bread, homemade crackers, slices of pear or apple, walnuts and a little honey all balance the salt rather than competing with it.
For wine, the classic French match is a sweet white like Sauternes, because the sugar softens the salt, while a fruity red goes well with the milder, creamier blues.
If you’d like to go further with pairings, my cheese and wine tasting e-book walks you through it.
Can you eat the rind?
Yes, where a blue has a rind, usually a thin dry crust, it’s edible. Taste a little and see whether you like it, and if you’d rather leave it on the side of the plate, plenty of people do. Blues sold wrapped in foil often have barely any rind at all, so the question doesn’t really come up with those.
Cooking with blue cheese
Blue cheese is salty, creamy and a little wild, and you only need a small amount for it to leave its mark on a dish.
Pear and blue cheese salad
This French bistro classic brings together crisp chicory (Belgian endive) or salad leaves, crumbled blue cheese and walnuts, with a walnut oil dressing. I make my own version with pear, and it’s just divine: pear and blue cheese salad. A simple dressing of walnut or olive oil and vinegar is all it needs, and if you have leftover roast beetroot or caramelised onions, they’re very happy in that bowl too!
Sauce au bleu
Blue cheese melted into cream is one of the great French bistro sauces. I like to keep it simple and toss hot pasta with a spoonful of blue cheese, a splash of the cooking water and a little cream if I want it richer, so the cheese melts into a loose, glossy sauce. With some steamed broccoli, mushrooms or peas stirred in, dinner is ready! The same sauce is also lovely over gnocchi or baked potatoes.
Tarte au bleu et aux poires
Blue cheese and pear are a well-loved pairing in the Auvergne, often baked together in a tart. Scatter small pieces of blue over pears, leeks, onions or roasted squash in a pastry case, pour the custard around and bake, and the cheese softens into pockets of savoury sharpness against the sweet filling. With a drizzle of honey and a green salad, it makes a very good lunch.
Tips for cooking with blue cheese
- Go gently: Blue cheese is strong and a little goes a long way, so start with less than you think and add more if you need it.
- Add it at the end: Stir blue cheese into sauces off the heat or right at the end, as too much heat makes it oily and grainy instead of creamy.
- Pick the right blue: Milder, creamier blues melt beautifully in sauces, and the crumbly, saltier ones are perfect in salads.
- Watch the salt: Taste before you season, because the cheese brings plenty of salt on its own.
FAQ
Is the mould in blue cheese safe to eat?
Yes, the blue in blue cheese is Penicillium roqueforti, a mould chosen specifically for cheesemaking and eaten in France for centuries. It has nothing to do with the fuzzy mould that grows on old bread or on cheese forgotten at the back of the fridge. If a blue cheese develops fuzzy white, pink, orange or black spots on the surface, or starts to smell sour, throw it away.
Can you freeze blue cheese?
You can freeze blue cheese, but the texture won’t survive intact, as a creamy blue turns grainy and crumbly once thawed. That makes frozen blue fine for cooking and disappointing on a cheese board. Crumble it, wrap it tightly, freeze it for up to about three months, and add it straight from frozen to sauces, dressings, soups and gratins.
How do you store blue cheese?
Store blue cheese in the fridge, ideally in the vegetable drawer at around 3 to 7°C (37 to 45°F). Wrap it in foil, cheese paper or baking paper (parchment paper), then keep it in a loosely closed box or bag. Avoid tight cling film (plastic wrap), which makes it sweaty and slimy, rewrap it when the paper gets damp, and keep it away from other cheeses so the mould doesn’t spread.
Why does blue cheese have lines of holes in it?
Those lines are the marks left by the needles used to pierce the cheese while it was young. The mould inside needs oxygen to grow, so cheesemakers push long stainless steel needles right through each cheese to create little air channels. The blue then spreads along them and into the cracks in the paste, which is why the veins often follow neat lines.
Why is my blue cheese turning brown?
A brownish tinge on the cut surface is usually just the cheese drying out and oxidising where it has been exposed to air, and you can scrape a thin layer off. It’s a sign the cheese needs better wrapping. If the brown comes with a slimy surface, fuzzy coloured spots or a sour or ammonia smell, the cheese is past its best and should go in the bin.
Explore all the cheese families
Final thoughts
Blue cheese looks intimidating if you didn’t grow up with it like I did, but it becomes a lot less mysterious once you know the mould is there on purpose and carefully looked after. Start with a mild, creamy cow’s milk blue, give it time to come to room temperature and eat it with pear or walnuts, then work your way up to the stronger, saltier ones when you feel brave!
Once it clicks, it’s that mix of salt, tang and creaminess, with something savoury underneath, that keeps you going back for another piece.
Which French blue cheese is your favourite, and which one won you over the first time? Tell me in the comments!
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