Microbes
STORIES

Words: Anthony Power  

Microbes

The unsung hero of food production

There is no questioning the fact that all four elements, earth, air, water and fire, play a fundamental role in our very existence (individually and as a whole), but when it comes to the food system, it is air that we humans really should salute.

Maybe it’s because we can’t see it, maybe because it’s just always there, but we all owe a debt of gratitude and respect to the air we breathe for centuries of service to the food system and helping to shape our very existence in the process.

Invisible to our naked eye (with man-made pollution being the exception), the air we breathe also provides a dense and stable environment that allows trillions upon trillions of microscopic bacteria to simply float around in the air amongst us (and inside us). They latch onto, feed on and rapidly multiply using pretty much whatever they god damn well please. And we are lucky that they do.

Make no mistake, this planet belongs to bacteria; it is quite literally their domain. Bacteria are some of the first life forms to appear on Earth and can be found pretty much everywhere, from soil to acidic hot springs, and from sea floor to radioactive waste. To put into context just how prolific these little critters are, there are around 40 million bacterial cells in a gram of soil and around a million in a millilitre of fresh water — their biomass exceeds that of all plants and animals combined. And they’re not just around us either, they’re all over us, and inside us. On you and in you there are around 39 trillion bacterial cells. This is about 30% more bacterial cells than actual human cells so statistically, you are more bacteria than you are human.

We all know there are good bacteria and bad, but there are a few strains of bacteria that, quite frankly, deserve a medal for their unwavering service to food production. The king of the microbes, or at least in relation to humans, is undoubtedly Lactobacillus. These little legends break down sugars into lactic acid and can be found in their trillions in your digestive and urinary systems, and in the fun parts of the body: the genitalia.

While these simple, microscopic organisms go about their business, the lactic acid they produce makes for something truly magical for us humans: fermentation. They are the ultimate secret ingredient. So secret an ingredient were these microbes and the role they played in food production that for millennia, we had no idea of their existence or just what the fuck was going on, but we liked the end product so we kept doing it.

These microbes are responsible for many of the foods we consume today. Bread, cheese, alcohol, chocolate, salami and Kimchi are only a few direct results of airborne microbes playing a critical role in the fermentation process— the element that make these foods so delicious. Without microbes and the carbon dioxide and lactic acid they produce, these foods would not exist as we know them. Just try to imagine a world without wine. No thanks.

While the thought of a world without booze is unimaginable, take into consideration how humans have literally evolved with bread, the humble loaf. Staple of many cultures around the world and quite possibly the invention that may actually have changed the course of human evolution forever. Bread has been a cornerstone of our diet since the dawn of agriculture and still today, in many cultures around the world, the thought of a meal without bread is unthinkable.

There are many speculative stories about how we first learned to make bread. There is evidence to suggest our prehistoric ancestors experimented with baking using a gruel from foraged starches and roots, mixed with water to form a paste, and cooked on hot rocks. But it wasn’t until around 5000 years ago that the Egyptians took it to the next level by beginning to leaven their bread.

While there is no direct evidence as to exactly when or how the Egyptians invented the first leavened loaf of bread, one of the most plausible explanations is that way, way back, in the region around Egypt fittingly known as the Fertile Crescent and The Cradle of Civilisation, some fool left his or her bowl of wheat grain porridge under the bed, only to find it a few days later bubbling away with a hive of activity. The original ‘mother’ to bread as we know it today. This fermentation happened as a result of yeasts, lactobacillus bacteria-producing carbon dioxide and lactic acid respectively. Unbeknownst to the founders, they created a product not only bigger than what they had started with, but more nutritional than the sum of its parts.

To this end, wheat very quickly became the best thing before sliced bread, and since then it has gone on to take the title of the most widely cultivated crop in history. Some may argue that wheat is the very crop that has enabled the human race to advance to where we find ourselves today, but it was the introduction of microbes to our wheat that really changed the game.

These days we call it sourdough and it has truly made a comeback, with more and more artisan bakers returning to those old ways of bread production, luckily for us. The gluten found within the flour traps the carbon dioxide produced by the yeasts as gas bubbles, while the lactic acid produced by lactobacillus gives the slightly sour flavour to the bread. When compared to mass-produced supermarket bread, it’s like comparing chalk and cheese. A pretty simple process, but without the presence of microbes, we’d be eating flatbreads under those smashed avocados.

Now while these microbes have quietly gone about changing the course of human evolution by giving us the cornerstone of our diets, they have also had our back with some of our other favourite foods. A close second (arguably more important than the facilitation of bread) is their Oscar-worthy performance in the production of alcohol: beautiful, sweet booze. For centuries, humans have been using fermentation to produce wine and beer and for almost as long, the brewers didn’t really understand what was happening to the mix. The end product was magnificent though and it got you drunk, so they just rolled with it.

Cheese is another by-product of microbial bacteria at work. Lactic acid bacteria converts milk sugar and lactose into lactic acid, which in turn lowers the cheese pH. That makes it inhospitable to many other potential spoilage bacteria, and at the same time, makes it equal measures of stinky and tasty.

The bacteria known as Propionobacter shermanii plays a key role in the cheese-making process because of its ability to digest acetic acid and turn it into that distinctly sharp, sweaty, foot-smelling propionic acid and carbon dioxide. It is that same propionic bacteria that can be found on the human body and is responsible for producing that unpleasant stench that can emanate from the body’s sweet spots.

Most of the moulds that grow on cheese are a species of Penicillim, and it is just two species of bacterium, P.roqueforti and P.glaucum, that are responsible for creating the blue moulds that give the unique flavour and texture to hundreds of blue cheese varieties like Stilton, Roquefort and gorgonzola — some of the most revered cheeses around the world. These unique bacteria can live in very low oxygen environments and the cracks within this style of cheese make the perfect home.

Soft-ripened cheeses, such as camembert, are produced by the presence of a mould called P.camemberti. These microbes produce an enzyme that break down the milk proteins and give rise to the characteristic ‘rind’ that encases the firm interior.

When it comes to cheese, there’s a well-known saying ‘the stinkier the better’, and it is microbes once again that are responsible for creating the room-clearing pong of cheeses like Munster, limburger and raclette. In these cases, the odour is caused by the presence of brevibacter linens, also called smear bacteria — not surprisingly, given the stench it produces in cheese, this is the same bacteria that causes foot odour.

To quote the late American poet, John Ciarid; ‘fermentation and evolution are inseparable’, and he couldn’t be more right, but the day we truly bow down in homage to microbes may be not too far into the future; scientists in Finland have apparently created a batch of single cell protein out of thin air using nothing but electricity and carbon dioxide. The food creating system uses a bioreactor to create electrolysis of the water, and with the carbon dioxide captured from the air and our little heroes, microbes, the end result of the reaction is a powdery, edible compound which is around 50% pure protein, 25% carbohydrates while the remainder is various fats and acids. Now Im going to take a guess and say it probably tastes like shit, but the simple fact that the United Nations estimate that there are currently around 900 million under-nourished people around the world, and with this number to increase to somewhere around 2 billion by 2050, well it might just be that microbes quite literally save our asses, again.

So take a moment over your next beer or slice of sourdough bread to say a little thank-you to these little troopers of food production. In fact, so many microbes gave their life so you could enjoy that beer so you really do owe it to them to drink more of it. Cheers.