Natural Cultures in Your Food
Why you can’t make bread and cheese on the same day
Reading Time: 4 minutes
Not much beats some bread and cheese, especially when they are both homemade. However, you can’t make (or at least start the culturing of) both on the same day in the same kitchen. This results in not-so-desirable cheese, although the bread should be fine. This is because of bacteria and yeast cultures spreading through the air to one another, but we will go into more detail about that later. Speaking of cultures in the air, let’s also look at some other naturally occurring cultures and how they can be used in the making of food.
Bread and Cheese
When beginning the culturing of milk to make cheese, you must take many precautions to avoid contamination from undesirable bacteria. All utensils are sanitized and everything scrubbed scrupulously. Yet, the one place where it is most difficult to control the bacteria is the air itself. That is why fast-growing cultures are so important for cheese-making. They are able to grow quickly enough to out-compete the other bacteria and microorganisms. Yet, even a reliable starter culture may struggle against another fast-growing culture: the yeast in your bread dough. When you make homemade bread, even though you may be using yeast start from a package, as the bread rises some of this yeast does disperse into the air. If you are starting a cheese culture the same day, the amount of yeast in the air can cause enough yeast to get into your milk and begin to proliferate. It will then compete with your cheese starter in feeding upon the nutrients in the milk. While this won’t necessarily make the resulting cheese inedible, it certainly won’t be what you were aiming for and you can’t guarantee that the difference is only because of the yeast and not from other contaminating bacteria. While yeast is sometimes used as a secondary culture to flavor cheese as it ripens, this must be done after the initial culturing into curds. Typically the yeast is used to coat the rind for some bloomy rind cheeses.
Traditional Cheese Bacteria
Today, most cheesemakers use a freeze-dried starter culture in making cheese because they are proven and consistent. However, before the modern era of safety and consistency, cheese was made using the bacteria already present in the raw milk. Usually, milk that had been expressed carefully to maintain the highest level of cleanliness possible was left to sour overnight, and some of that soured milk was used to inoculate the vat of fresh milk the next day in the cheese-making process. However, the results were not always consistent, and there was a higher chance of food-borne illness. The most interesting aspect of using the milk’s natural bacteria is that the bacteria would differ by region, thereby making cheeses from different areas taste completely different even though they may be processed the same in every way. This is why Parmigiano-Reggiano cheese can only be made in the Parma or Reggio Emilia provinces of Italy with just a little bit of neighboring provinces being included in the production area.
Ahhh, the maker of sourdough: wild yeast. You can find wild yeast everywhere, but it needs a good medium in order to culture enough to be recognizable. There are different ways to “harness” or “catch” wild yeast. There may be enough just in the air of your kitchen to find its way into a flour and water mixture, but it loves to live on sweet fruits. Some beer makers have been known to set their beer start, called wort, under a fruit tree with a simple cheesecloth over so the yeast can fall in and begin fermenting.
Bacteria + Yeast = Love
While wild yeast is what causes sourdough bread to rise, it is the bacteria that truly lend their flavor to the final product. Lactic and acetic acid produced by bacteria in the ferment give the characteristic sour flavor of sourdough. However, different bacteria strains that are indigenous to areas can cause the flavor to vary. Your kitchen with its own blend of bacteria and yeasts will give its own unique flavor different from your friend’s kitchen, although it may be subtle enough not to notice if you live in the same area. For example, those who know sourdough know that the sourdough bread in San Francisco is the best. This is because of the particular blend of bacteria that are in the area helping to flavor the sourdough bread.
Lactobacilli on Your Vegetables
The vegetables growing in your garden are covered in bacteria. Now before you go hosing antibacterial onto the pumpkin patch, know that many of these bacteria are very good for you. One particularly good type of bacteria is the Lactobacillus family. These produce lactic acid when they proliferate. Lactic acid is an excellent preservative for those same vegetables, and you can utilize the Lactobacillus bacteria to ferment vegetables for storage. Now I do recommend researching more into this process, but I can tell you just the basics. Using a high-mineral unrefined salt, you can encourage those lactic acid-producing bacteria to multiply rapidly in your vegetables. Fermenting vegetables is more than just making sauerkraut or cucumber pickles. You can ferment many of the vegetables growing in your garden, only do it quickly after harvest before those wonderful lactobacilli begin to die off.
While our modern world often favors packaged starter cultures for consistency, wild cultures of bacteria and yeasts have been used for thousands of years to make or preserve food. You can still utilize these cultures today in your homesteading practices.
Originally published in the March/April 2020 issue of Goat Journal and regularly vetted for accuracy.