Sep 23 2026
Traditionally, the perception of cheese with distinctive holes in it draws the cheese lover to Swiss cheese. It adds great characterisation and personality to those types of cheese, but there are French variations also, which follow the same science and present a cheese with regular-shaped holes in the surface. Emmental and the French version of Gruyère are amongst the most popular French cheeses, and not just for their eye-catching appearance, but people do often wonder how and why these holes develop.
In short, cheese develops holes as a result of a combination of bacteria and carbon dioxide, and in this article we will explain the science behind that.
When herds graze the fields they eat a variety of natural products, such as hay, grass and even soil. As a result, the raw milk they produce contains bacteria, and specifically a bacteria culture called Propionibacteria. When a cheese is pasteurised, these bacteria are killed off and have no effect, but in the past, cheesemakers discovered that as the cheese fermented with these bacteria still present, the bacteria produced carbon dioxide, which formed bubbles or holes in the body of the cheese.
Cheese is now pasteurised to kill off bacteria which can contribute to ageing, but some cheesemakers add Propionibacteria back in, specifically to produce the distinctive holes and to give certain cheeses their renowned personality. The temperature-controlled rooms that cheese is aged in also contribute to the bacteria consuming lactic acid in the cheese and releasing carbon dioxide, the temperature also keeps the texture consistent, which is a big factor in the holes forming. Technically, the holes form because the carbon dioxide can’t escape. The rind of the cheese traps the air in and forms the holes, albeit these types of cheese aren’t known for a particularly hard or thick rind. The carbon dioxide in the cheese also influences the flavour profile of the cheese.
The openings or holes in French cheese are usually called ‘eyes’. In Emmental and Gruyère they are quite evenly spaced out and are circular and regular in shape, although the size can vary between a petis pois and a blueberry size. The eyes are created by tiny pockets of gas in the cheese which creates rounded cavities. Emmental has a Golden rind and is a very yellow cheese that is delicate and supple in texture, but has an acidic and fresh taste with a rich aftertaste and a fruity aroma. Its mild taste makes Emmental a family favourite and a popular cheese for use in salads, gratins or as a snack.
Gruyère originates from the prairies of Savoie and Franche-Comte and was originally made to feed huge farming communities in the winter. Gruyère is ripened in two stages, and when the characteristic holes start to appear, it is moved to a cold cellar where fermentation can be better controlled. Gruyère is also golden in colour with a smooth and springy texture. The taste is fresh and slightly sweet and, like Emmental, is an everyday cheese with all-rounder qualities.
You can enjoy both these ‘holey’ cheeses by ordering from Sodiaal UK today.Traditionally, the perception of cheese with distinctive holes in it draws the cheese lover to Swiss cheese. It adds great characterisation and personality to those types of cheese, but there are French variations also, which follow the same science and present a cheese with regular-shaped holes in the surface. Emmental and the French version of Gruyère are amongst the most popular French cheeses, and not just for their eye-catching appearance, but people do often wonder how and why these holes develop.
In short, cheese develops holes as a result of a combination of bacteria and carbon dioxide, and in this article we will explain the science behind that.
When herds graze the fields they eat a variety of natural products, such as hay, grass and even soil. As a result, the raw milk they produce contains bacteria, and specifically a bacteria culture called Propionibacteria. When a cheese is pasteurised, these bacteria are killed off and have no effect, but in the past, cheesemakers discovered that as the cheese fermented with these bacteria still present, the bacteria produced carbon dioxide, which formed bubbles or holes in the body of the cheese.
Cheese is now pasteurised to kill off bacteria which can contribute to ageing, but some cheesemakers add Propionibacteria back in, specifically to produce the distinctive holes and to give certain cheeses their renowned personality. The temperature-controlled rooms that cheese is aged in also contribute to the bacteria consuming lactic acid in the cheese and releasing carbon dioxide, the temperature also keeps the texture consistent, which is a big factor in the holes forming. Technically, the holes form because the carbon dioxide can’t escape. The rind of the cheese traps the air in and forms the holes, albeit these types of cheese aren’t known for a particularly hard or thick rind. The carbon dioxide in the cheese also influences the flavour profile of the cheese.
The openings or holes in French cheese are usually called ‘eyes’. In Emmental and Gruyère they are quite evenly spaced out and are circular and regular in shape, although the size can vary between a petis pois and a blueberry size. The eyes are created by tiny pockets of gas in the cheese which creates rounded cavities. Emmental has a Golden rind and is a very yellow cheese that is delicate and supple in texture, but has an acidic and fresh taste with a rich aftertaste and a fruity aroma. Its mild taste makes Emmental a family favourite and a popular cheese for use in salads, gratins or as a snack.
Gruyère originates from the prairies of Savoie and Franche-Comte and was originally made to feed huge farming communities in the winter. Gruyère is ripened in two stages, and when the characteristic holes start to appear, it is moved to a cold cellar where fermentation can be better controlled. Gruyère is also golden in colour with a smooth and springy texture. The taste is fresh and slightly sweet and, like Emmental, is an everyday cheese with all-rounder qualities.
You can enjoy both these ‘holey’ cheeses by ordering from Sodiaal UK today.
VIEW ALL OUR NEWS