Is Mould on Goat’s Cheese Normal? How to Tell If Soft Cheese Is Still Safe to Eat

In the cheese world, makers and mongers tend to be a bit blasé about the mould that can be found on cheese.  For people who are used to a more sanitised version of food that is acquired from the supermarket though, mould is often seen as worrying, and something to be cut off or discarded.  It is important to realise that there is a difference between mould that is intentionally added to cheese and is perfectly safe to eat, and mould that develops on the cut surfaces of cheese after opening, which is spoilage.

Our own cheeses are made to encourage mould to be present on the rind of our soft goats’ cheeses - Blackmount and Elrick Logs.  The yeast like mould (Geotrichum) is added to the milk as part of the making process at the same time as the cheese culture.  In fact, as part of our process, the cheese is kept in our hastening room to encourage the mould development through control of temperature and humidity.  We encourage the development of geo (white mould) which turns the skin of the cheese wrinkly and velvety.  It also helps to develop the rind or skin of the cheese, helping to build it, and encourages soft creamy textures just under it as it matures.  This is referred to as “breakdown” under the skin, and is what happens as the cheese gets older and more potent.  It is what helps to give the cheese an earthy, mushroomy flavour, encourages that nuttiness and reduces bitterness.  When we are tasting a batch before we release it, we assess the development of the mould and the tastes and textures that it produces. 

However, Geotrichum also raises the pH (reduces the lactic acid) on the surface of the cheese and this encourages the growth of blue and green moulds.  It is not unusual to find spots or blotches of green or blue and the occasional spot of fluffy grey on our cheeses.  Are these safe to eat?  Absolutely – historically, lots of cheeses that mostly present as off white today (such as brie or camembert) would have been covered in blue, green and black spots.  Today, we try to discourage too much of this, because it doesn’t look as appealing to the consumer but it is all part of natural development of rustic, farmhouse cheese, and adds to its character.

When a cheese such as a cheddar style cheese such as Corra Linn is cut it develops another rind over time on the cut face, it may also dry out slightly so might not taste as it was intended in that case you can scrape or cut the face and the internal part of the cheese should still be good to eat, if it has dried out too much it might be better for cooking. If you think of a supermarket factory produced brie in a slice they are sometimes sold with a full coating of white mould even on the cut sides, this is the same thing the sides have simply developed a new rind. You might even get a new cheese if you store all your cheese together a strong white covered brie style cheese stored with a blue cheese for instance could develop a white rind given the right conditions in your fridge.

We are used to the white mould on our soft cheeses such as Blackmount and Elrick Log, and the blue mould in and on blue cheeses such as Lanark Blue.  In fact, we add these during the making process, and take steps during the development of cheese to encourage these moulds to grow.