On Jul 22-23 I participated in a Fermenting workshop with Sandor Katz, the author of The Art of Fermentation and Wild Fermentation. Shelburne Farms, just outside Burlington, Vermont hosted the event. If you’ve been to Shelburne Farms before, we were in the Coach Barn for the event. Over two days we covered the basics of fermenting, lactic-acid fermentation of vegetables, a hands-on exercise making our own ferment, (day 2) dairy fermentation, fermenting grains and legumes, and fermented beverages like kombucha.
In general, I was impressed with Mr. Katz knowledge and experience with fermenting. He clearly has a passion for the art and has experimented with a lot of interesting techniques. Admittedly, that was where my enthusiasm stopped. Sorry to drag work into my blog, but I was criticizing Mr. Katz classroom technique throughout the workshop and found his teaching to be lacking. The entire second day was blocked out into 2-hour chunks with 30, 60, and 30 minute breaks between (8 hour day total). Most of the content was basic lecture with a few quick demonstrations (blueberry soda and yogurt). We had a hands-on activity after lunch on day 1, but day 2 was uninterrupted sitting. To compound the fatigue from sitting, the space had uncomfortable chairs and was not air-conditioned. We were pretty short tempered and sweaty in a 90+ degree room with little moving air. I didn’t get much out of the second day, even when I abandoned my uncomfortable chair to stand in the back of the room and hope to catch a little breeze. I did learn a lot, and the course definitely met my objective of motivating me to make better kraut and kimchee. I think I may even start to make our own yogurt.
I had three major takeaways from the event:
- Everything is rotting, being digested and broken down by microbes. Fermenting is just using different techniques to control the process of rotting food by favoring different microbes over others. Malted barley plus water makes sugars that can be digested by yeast to make alcoholic beer, or by other molds to make nasty undrinkable stank.
- Fermenting refers to two different processes. Process 1 is where yeast convert sugar to alcohol in the presence of oxygen, then acetobacteria convert alcohol to acetic acid (vinegar), again, still with oxygen. Process 2 is where lactic acid bacteria convert carbohydrates and sugars to lactic acid in the absence of oxygen. The following table may help clarify the difference between the two foods:
Process 1 Process 2 Microbe Yeast Lactic Acid Bacteria Substrate Sugar Carbohydrates and Sugar Oxygen Present Absent Byproduct Alcohol + CO2 Lactic Acid + CO2 Secondary Process Acetobacteria convert
alcohol to vinegar
Food Characteristics Alcoholic, Bubbly Tart, tangy, softer Tasty Examples Beer, Wine Sauerkraut, Yogurt
- Fermentation has become very “faddish” due to confusion and misinformation about the well-supported versus not-so-well supported benefits of fermentation. Fermentation has three well-known and supported benefits: pre-digestion of food, preservation of unstable foods, and increased diversity of gut flora. With pre-digestion, the bacteria or yeast break down the substances in the food into simpler forms. Complex carbohydrates (e.g. cell walls) become simple carbohydrates (sugars), and complex sugars (disaccharides like sucrose or lactose) become simple sugars (monosaccharides like fructose or glucose). Fermented foods are more stable over time – sauerkraut lasts longer than a plain cabbage, and yogurt lasts longer than milk. Additionally, fermented foods are home to a culture of microbes that have been shown to have benefits for diseases of the gut.The confusion comes from the secondary effects. In the process of fermenting foods, some people argue that the food becomes more nutritious, makes certain nutrients more available for the body to absorb, and may have broader effects on the whole immune system of the body. Some participants at the workshop even argued (from their own personal experience) that fermented foods helped them recover from cancer, HIV, and other serious diseases. While these are nice stories to tell, the research just doesn’t pan out to support these effects. I’m working on a systematic review of the literature and when it gets complete, I’m happy to provide detailed citations. In the few areas where there have been studies, the studies have been small and results are non-conclusive. In the absence of good evidence, it’s fine to eat fermented foods because you like to eat them and drink them, but don’t do it because you think it will be some health panacea. It’s just a fad.
I know them’s fightin’ words, so please give feedback in the comments.