Writing about cheese rind got me thinking about the role of microorganisms such as bacteria and moulds have in cheese-making – after all, without them we wouldn’t have cheese! Like cheese rind, it seems that many of us are a bit wary of mould, maybe because it is usually associated with ‘old’ or deteriorated food. But as far as cheese is concerned there is nothing ‘wrong’ with most moulds found on or even in your cheese; moreover, they play a significant role in producing some of the most delicious varieties of flavours and textures in many cheeses.

Cheese-makers have been manipulating moulds and bacteria to develop different flavours and textures for many hundreds of years. When or how they first started to harness this natural phenomenon is uncertain. Of course, there are a number of myths and legends associated with it, but (forgetful shepherds and milk maids aside) what we can deduce is that many of the limestone caves, cellars and barns where cheese was most often stored would have provided the ideal environment in which moulds and bacteria grow and thrive. Over time cheese-makers learnt to recognise which moulds create the most desirable cheeses and sought the optimum conditions in which to store their cheese to allow the preferred moulds to grow.

Interestingly, we have no qualms about eating the ‘blue’ (mould) in blue cheese such as Stilton, or even the white mould of Brie – perhaps because it’s expected? But what about Cheddar Cheese?

In more recent years blue mould in cheddar cheese has mostly been considered a defect and often rejected. Indeed, you’ll be hard pressed to find any Blue Cheddar for sale on any shelves of any supermarket! To avoid wasting their efforts producing ‘unsellable’ cheese, all cheddar cheesemakers now aim to reduce the chances of their cheese containing any natural ‘blue’. Producing large scale block-formed cheddar and maturing in plastic bags prevents mould developing in most cheddar cheese today.


For those who produce (intentionally) blue cheese for example Stilton, Roquefort or Castello Creamy Blue, a mould, such as Penicillium roqueforti is added to the milk before the cheese is made. Later, during maturation, blue veins develop within the body of the cheese.

For us ‘natural blueing’ can occur when the outside rind cracks or gets damaged, enabling an access point for natural environmental moulds to enter the body of the cheese. Our cheese is cloth bound and long-matured in cool humid store rooms (including the natural caves in Cheddar Gorge) which are ideal environments for traditional cheddar cheese development, but so too for mould spores! If they manage to get through our (normally) protective rind, mould spores will thrive in the body of our cheeses.

Natural blueing in cheese was much more common before more efficient methods of making and storing cheese were developed; during the 19th Century Wensleydale was actually considered to be a ‘blue cheese’ and naturally blue Cheshire Cheese was a local delicacy commonly known as ‘Green Fade’.

Modern cheese-making is more refined these days where specific strains of blue mould can be selected to create exact flavour and texture profiles by the cheese maker.


Although the unrefined natural blue mould found in our cheddar isn’t quite the same as the more refined, intentional strains used in modern style blue cheeses, it still influences the cheese in a similar way; producing a subtle and interesting ‘blue’ flavour. Despite intending to make a non-blue traditional cheddar cheese, we do occasionally discover these blue veins – only at the point when we cut open our huge 25Kg cheddars!

Our authentic cheddars have drier, more ‘friable,’ crystalline textures so are susceptible to cracks forming on the outside rind as they mature and dry over time. We have to take great care to avoid knocking or bumping our cheeses when we turn them whilst they mature, as careless handling could very easily crack the rind.

We like to think of it as ♥ a happy accident ♥ , because natural blue cheddar is always a surprise for us. It’s delicious and interesting!

It’s something unusual to talk about with the visitors to our shop in Cheddar.

I always like to think of it as getting two cheeses in one!

If you’d like to try our Natural Blue Cheddar you can visit our shop in Cheddar Gorge or buy it online HERE.