In The Energy Cost of Food I note that household energy use associated with food sourcing, preservation, processing and preparation represents about a quarter of total food system energy use. Since consumers have the most control over energy used in their homes it makes sense to ponder how to reduce it, if for no other reason than to save money on utility bills and to create a buffer against the agonies associated with power outages. One way to reduce household energy use associated with food is to adopt fermentation as a primary means of food preservation. The process of fermentation involves allowing particular types of bacteria to digest the sugars in foods, releasing lactic acid as a waste product that acidifies the food and prevents spoilage.
Sandor Ellix Katz, who wrote Wild Fermentation over a decade ago and The Art of Fermentation more recently, is a leader in the resurgence of fermentation and I had the pleasure of attending a two day workshop with him at Shelburne Farms over the past two days. While I already knew the basics of the process, the workshop opened up several new doors for inquiry and also gave me a chance to mingle with over a hundred other people from Vermont and surrounding states who shared my interest in food and traditional health.
The first day of the workshop focused on fermenting fruits and vegetables, and after lunch the 100 or so attendees chopped vegetables to fill a jar to ferment at home. I’ve done this 100 times, but for many people this was their first experience preparing vegetables to ferment so it was fun interacting with people and listening to the questions that cropped up. For this recipe we chopped a mixture of cabbage, radishes, turnips, carrots, onions, garlic and perhaps a few other things, and while mixtures of vegetable ferment taste reasonable to me I prefer ferments that focus on one or at most a few vegetables, so I elected not to fill a jar and let others take a bit more.
The second day of the workshop was more varied; Sandor started the morning lecturing on different types of dairy ferments, including making yogurt, kefir and ending with a brief discussion of cheese. I was intrigued to learn that commercially available kefir isn’t really kefir. Traditional kefir typically has an alcohol content around 1 percent, but given modern food laws this would have to be marketed as an alcoholic beverage so commercial producers adjusted the microbial cultures to constrain the alcohol production. The result is something vaguely like traditional kefir, but it isn’t really kefir, but people want kefir so this label is used even though it isn’t accurate. The final segment of the workshop detailed with grain and legume fermentation, which I’m admittedly not interested in, as well as a brief discussion on fermenting meats.
While I introduced fermentation as a means of low-energy food preservation, it does so much more. Fermentation, particularly of plant foods such as fruits, vegetables and grains, serves to predigest the food and break down nutrient complexes to make nutrients – particularly minerals - far more bioavailable. Another service fermentation provides is detoxification; some anti-nutrients and other toxins in foods can be broken down during the fermentation process, making the food not only more palatable but also less likely to cause harm when eaten. A final benefit of fermentation that complements these earlier two benefits is nutrient enhancement. The microbial action inherent in the fermentative process creates nutrients in foods that weren’t present or were present in much lower quantities, among them B vitamins, certain antioxidants and some short-chain fatty acids.
In all fairness, I do want to warn against eating too much fermented foods. They are quite acidic, with pH values commonly below 3 or 4, so if eaten too frequently or in large helpings the acid can degrade tooth enamel much like constantly slugging soda or vinegar. Eaten in small quantities though, these foods’ acidity shouldn’t cause too much of a problem and they certainly offer a range of benefits. Indulging in fermented foods to excess without any prior experience with them can also cause stomach or intestinal upset for some people, so a relationship with fermented foods is best started slowly. Despite these cautions, I certainly enjoy eating fermented foods on a regular basis and experiment with making them myself to cut costs, and encourage others to do the same.