What is fermentation?
Sauerkraut, kimchi, olives, and pickles; yogurt, kefir, and cheese; wine, beer, and vinegar; soy sauce, tempeh, and sake – sound familiar? These are fermented foods that have evolved from ancient tradition into sophisticated craftsmanship. The basic process, however, remains unchanged: Fermentation is still the slow decomposition of carbohydrates (natural sugars) in food by microorganisms. This method of preservation was a way of life before refrigeration, and its secrets were handed down from parent to child. Until recently, fermentation skills were slowly being lost. Yet, there has been a resurgence of interest, which is keeping the tradition alive.
Beer and wine are as much of an art as sauerkraut and pickles, yet with different microbes.
The difference is in the type of microbe(s) used for fermenting a specific food. Fermented foods can be classified by the type of microbe used in the fermentation process, including yeast, mould, bacteria, or a combination. Changing the type of microorganism acting on a certain substrate (food) will yield vastly different end products.
Lacto-fermentation: a subset of bacterial fermentation
Unlike yeast and mould fermentation, fermentation by lactic acid bacteria, lacto-fermentation, produces a sour, tangy flavour characteristic of fermented vegetables, dairy, and fruit. Some love it and others, well, it may take some time for them to come around.
This process is exclusively anaerobic (without oxygen) since all lactic acid bacteria involved in lacto-fermenation are intolerant to oxygen (anaerobes). These bacteria transform natural sugars into lactic acid and carbon dioxide with smaller amounts of acetic acid (vinegar) and ethanol. In the presence of oxygen, mould and yeast grow. Left unchecked, these microbes will spoil your ferment.
Health benefits of lacto-fermented foods
Lacto-fermented foods contain beneficial living microbes that improve gut health, thus health overall. Not all microbes involved in fermentation have known health benefits; that is, not all fermented foods contain probiotics, living microorganisms that when taken in sufficient amounts confer health benefits. Many lacto-fermented foods, however, do contain probiotics when fermentation is done properly (i.e. in an anaerobic environment). Probiotics make us heathy by:
• strengthening and stimulating the immune system,
• producing vitamins in the gut,
• enhancing the gut barrier against harmful bacteria,
• preventing heavy metals absorption, and
• reducing inflammation
“The problem with killing 99.9 percent of bacteria is that most of them protect us from the few that can make us sick.”
― Sandor Ellix Katz, The Art of Fermentation: An In-Depth Exploration of Essential Concepts and Processes from Around the World
Lacto-fermentation also causes a nutritional explosion. New nutrients are made, namely vitamin B1, B2, B3, and vitamin K2. Others, such as vitamins C and phytochemical, are multiplied many fold. Larger nutrients like starch, fiber, and lactose are pre-digested, which is helpful for people with digestive difficulties. Anti-nutrients, which are compounds that bind minerals and inhibit absorption in the intestine, are inactivated. Nutrients that would otherwise degrade due to oxygen are preserved. If you want a super food, lacto-fermented foods, especially lacto-fermented vegetables, are your jack pot!
DIY Vegetable Fermentation
Fermentation on a small-scale at home enables you to develop ferments reflective of your flare. Do you like your sauerkraut really soured over lightly soured? Do you like you dill pickles with a strong garlic presence? Or do you like lemon-rind and fennel seed with your brined pickled beets over the classic beet-orange-cloves flavour? These are aspects you, as a home fermented, can decide on. Your ferment will not taste exactly the same as traditionally fermented vegetables in the store – and that is okay. This uniqueness is actually welcomed, and will enhance your cooking and eating experience. Michael Pollan says it well:
“To ferment your own food is to lodge a small but eloquent protest – on behalf of the senses and the microbes – against the homogenization of flavors and food experiences now rolling like a great, undifferentiated lawn across the globe. It is also a declaration of independence from an economy that would much prefer we remain passive consumers of its standardized commodities, rather than creators of idiosyncratic products expressive of ourselves and of the places where we live, because your pale ale or sourdough bread or kimchi is going to taste nothing like mine or anyone else’s. ”
― Michael Pollan, Cooked: A Natural History of Transformation
ByDesign Nutrition & Health focuses on empowering people with knowledge of fermentation and skills to make a habit of fermenting vegetables at home. Two basic methods of vegetable fermentation are taught the introductory class: dry brining for shredded vegetables and brine pickling for coarsely chopped and whole vegetables.
Essentially both methods involve:
- Choosing fresh, local, and organically grown vegetables – the fresher the better.
- Chopping or shredding vegetables to expose surface area, which is important for brine formation and extracting sugars from vegetables into the brine.
- Salting to limit growth of unwanted microbes, preserve crunchiness, control the rate of fermentation, and draw brine from vegetables.
- Packing shredded vegetables (kimchi or sauerkraut) or whole or coarsely chopped vegetables into the fermenting jar.
Taking the babysitting out of fermenting
When desirable bacteria, mould, and/or yeast are involved, successfully fermented products with favorable texture and flavour result. When undesirable microbes are involved, unintended spoilage occurs. Mould, for example, is favorable for fermenting cheese, but spoils sauerkraut. Only when desirable microbes grow on intended foods at the right times under favorable conditions, do pleasing fermented products result.
Adapting a clamp-lid jar with an airlock takes the hassle out of fermentation. With traditional aerobic methods, such as in a crock, skimming mould daily is required. In the anaerobic jar system sold by ByDesign, mould cannot grow since it requires oxygen. Additional hurdles are applied to minimize unwanted microbes while favouring desirable microbes. Fermentation is all about manipulating factors at certain stages of fermentation to inhibit the growth of select microbes and advance the fermentation stages. The main hurdles used are:
• and the absence of oxygen (anaerobic), discourage the growth of spoilage and harmful microbes.
These hurdles and many other aspects of vegetable fermentation for optimizing its nutritional benefits are explained in more detail in the Vegetable Fermentation Class and Workshop. Look for one near you or contact Sarah if you are interested in hosting a class and having her present.