It doesn’t smell like cheese…it smells like lactic acid bacteria!

Are you one of those that the more intense the smell of cheese is, the more you want to sink your teeth into it? Then this article is for you, because here we’ll explain the function of lactic acid bacteria in the production of cheese, which is responsible for both its taste and smell. Let’s go!

How are cheeses made?

There are more than 2,000 varieties of cheese in the world, which can be classified according to the various types of milk they are made from and how long they mature, however, they all share a process that consists of these four main steps:

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1. Fermentation

This is the period when the milk sugar is converted into lactic acid by means of bacteria, which gives rise to rennet (this half-liquid, half-solid substance that will eventually become our cheese). It is during this process that the cheese masters will add certain types of bacteria to give each cheese its distinctive flavor and aroma. 

2. Curdling

Once we have the rennet, it can be cut with a lyre, a metal grid that helps to separate the solid bit (curds) of the rennet from the liquid (whey). 

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3. Draining

This part of the process strains our future cheese to remove as much liquid as possible. Cheese cloth or presses can be used to help squeeze out the whey. 

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4. Maturing

This step requires patience, since it consists of placing the wheels of cheese in ripening caves or controlled chambers in which humidity, temperature, and air are well-regulated. And then we wait.

The colonies of bacteria used in the fermentation process of cheese making are indispensable since they are responsible for creating the characteristic smell and flavor of each cheese. They can be categorized into two main groups: mesophilic bacteria (which withstand medium temperatures) and thermophilic bacteria (which are used for cheeses that require higher temperatures). Here are a few examples.

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  • Streptococcus thermophilus: is used in the production of Swiss and Italian cheeses, since it is a thermophilic bacterium that can reach high temperatures.
  • Propionibacterium spp.: is responsible for the distinctive smell and characteristic holes of Emmental cheese.
  • Aspergillus spp.: is a type of filamentous fungus that helps to reduce the acidity of rennet, which is involved in modifying the texture, aroma, and appearance of certain types of cheese, like camembert and Roquefort .
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Armed with this knowledge, are you ready to try and make your own cheese?

Warning: remember that not all microorganisms are beneficial to health, so if you are going to use unpasteurized milk, you should let your cheese mature for at least a couple of months so that all pathogenic elements are eliminated.

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