What is fermentation and why you should start fermenting now

I could copy-paste some technical definitions (and maybe will at some other stages, because it’s good to learn and challenge ourselves), but to make it simple: when applied to food, fermentation is a process through which chemical changes occur in food. More specifically, when fermenting food we aim at creating an environment where specific and desirable microorganisms can thrive. These microorganisms can be bacteria, yeasts, or molds. Why would we want them to thrive? Firstly, because they produce enzymes, which transform our food (more on this below). Secondly, when we create an environment that is very friendly for these known and safe microorganisms, by thriving they will keep at bay other species or strains of bacteria, yeasts and molds that might be bad for us.

Examples of foods and processes that employ these microorganisms:

• Sauerkraut and Kimchi: mainly lactic acid bacteria (L.A.B. from now on)
• Yogurt: (L.A.B.)
• Parmesan and other cheese: (L.A.B.)
• Sourdough/Levain: wild yeasts, L.A.B.
• Miso and soy sauce: molds (Koji is made with a “domesticated” mold, Aspergillus Oryzae), L.A.B
• Wine: yeasts
• Sake: molds (Koji)

I will go more in details on how to create these environments through the recipes, but if you are really into it, I advise you to check the section “What Inspires Me” for book and resources recommendations.

For now, let us focus on the main question: why would I get interested? Why would I buy fermented food or make it at home?

Fermentation is so fascinating. It is something that has been done by humans for food preservation and transformation purposes for thousands of years. Although it is a significant part of the processes used for making food (industrial or artisanal), it was partially out of fashion for home cooks and restaurants (if you maybe exclude some cultures where fermented foods are everyday staples, especially in Asia – I think of kimchi and miso). It is now coming back like a big wave, heavily affecting the restaurant industry and the way home cooks prepare their food. A first example is Noma (Copenhagen, Denmark), which is considered one of the best restaurants in the world, if not the best and most interesting. Noma’s chef René Redzepi and head of fermentation David Zilber² run a research laboratory for fermentation that is completely independent from the daily routine of the restaurant. They wrote “The Noma Guide to Fermentation”, which I urge you to buy and devour if you are interested in the topic. Many smaller restaurants all over the Western world are also employing fermenting techniques. There are incredible results arising from the blending of world cultures and food traditions. For example, Koji is as important for Japanese cuisine and food products (think sake, miso, natto, soy sauce) as yeast is in Western cultures (think bread, beer, wine), but it is now being employed by Western chefs and home cooks to age and cure meat and cheese, apparently with enormous success! I have not been lucky enough to try koji-cured saucisson or coppa or bresaola yet, but I literally cannot wait to do that.

Fermentation is for everybody. It is not difficult. You just need to learn the basic principles and apply them. For some types of techniques, these principles can be very simple. For example, for a by-the-book L.A.B. fermentation of vegetables: measure salt as minimum 2% of total the weight of the vegetables and water; use a very clean jar; once you put them in a jar, use some weights to keep vegetables submerged. That is it! And do not be mistaken: fermentation is not for people that are brave and adventurous. I have always been a scared cat, I throw things out if they are 1 day past their expiry date (depending on the product). When I saw fermentation videos on miso I loved them but I thought “I could never keep something in a jar for a full year and then trust it”. But here we are, with an 8-month old miso in my cupboard. I taste my miso with no worries, because I studied, because I have control, because I understand the process and what I am doing to make it work. And I will share all that with you.

But apart from the romance and the fascination, apart from riding the wave as obsessed cooks, there are several reasons why you should get involved and ferment. Here is why I do it:

• Health benefits: although creating cultures and colonies of microorganisms you cannot see sounds scary at first, if you do it properly you will have an army of microbes working for you (it is very easy to do in most cases, e.g. L.A.B. fermentation. These microbes will effectively pre-digest your food, by converting carbohydrates into sugars, sugars into alcohol, and alcohol into acetic acid. More importantly, enzymes will break down proteins into amino acids, which are the building blocks of life. They are needed to build your muscles and other parts of your body.
  Therefore, by eating fermented food, you would probably have a higher rate of absorption of proteins and other nutrients¹. Moreover, and in my opinion more importantly, the fermentation process creates by-products and transforms food in a way that your gut’s microbes will love. The live bacteria you eat in yogurt and other unpasteurised fermented food will not necessarily live for a long time in your guts, but their “pre-digestion” of food will break down starches and proteins in a way that the bacteria in your guts will love.
  I do not think it is my place to explain why you want to have a healthy community of bacteria in your guts, do research it and make your mind up if you are not convinced. It is generally associated with better digestion, better hormonal control (which will affect your feeling of hunger and satiety), good effect on psychological status.
• Flavour: by breaking down food into its components, especially breaking proteins into amino-acids, the fermentation process creates food with a lot of umami taste. Umami is one of the five basic tastes, and it is associated with a savouriness that hits your tongue and taste receptors in several places. Think of the feeling when parmesan cheese or soy sauce hit your tongue, or when you eat a delicious meat broth, or when you bite into a tomato. Our sense taste has evolved in a way that make us recognise and love some amino-acids, because they are very valuable for building parts of our body. Therefore, not only it is good for you, but you are also likely going to love it. Clearly, the setback of many fermented food I have mentioned is that they are very salty (so they are good for you in small measures), but it does not have to be! For example, sourdough bread has a similar percentage of salt to artisan breads made with commercial yeasts.
• By unlocking flavours and nutrients, with the bonus also of helping preserve the food, fermentation can help have a lower impact on the environment and world resources. By allowing us to absorb more protein and nutrients, some fermentation processes might prove to make some food as protein-efficient as some meats, especially when considering the protein cost of raising the animal for the meat (e.g., by feeding it with protein-rich grains)¹. This alone is not enough to change the balance of the world resources, but it is a point to acknowledge.

¹Read “The Book of Miso” by Shurtleff and Aoyagi to have a more in depth description of how Miso and Soy Sauce can provide as much protein as chicken (in % of weight), due to the higher absorption rate. They also provide very interesting information and stats on world famine (although the book now is a bit old) and show how fermenting soy could increase availability of resources and potentially help reduce world famine thanks to the higher protein return compared to raising cows by feeding them soy and eating beef.

²David recently resigned from Noma to pursue other challenges, you can follow him on Instagram (david_ziber).