Eric Garza

Musings on food, energy and adaptation

The Art of Fermentation

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.

KatzGarzaSandor 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.

Return on Investment

In many of my food-related posts I present data on the energy inputs needed to produce food relative to the amount of food actually produced, yielding a handy ratio useful in assessing input-output efficiency for these systems. This approach is a particular application of the idea of Return on Investment, often abbreviated as ROI. Since ROI plays an important role in my own strategic planning and in how I analyze systems, I thought I’d explore the concept in greater detail.

CoinReturn on Investment is typically calculated as a ratio with the return an investment is expected to yield over a given timeframe in the numerator and the investments required to deliver that return in the denominator. ROI is most often used in financial circles, where returns and investments are measured in dollars or some other currency. Since the goal of an investment is to generate the largest return possible, ROI can be used to prioritize alternative investments, hopefully singling out those that will offer the greatest overall return.

While the idea of ROI originated in financial circles, anthropologists and ecologists also use the metric. Richard Lee, an anthropologist, used an ROI framework back in the 1960s to study the labor energy indigenous peoples invested to find food, and calculated ratios of food energy return on labor energy invested for their tribes. Ecologists, notably Howard Odum and later Charles Hall, did the same within studies of ecology, and Hall is well known for coining the phrase Energy Return on Investment and its associated acronym EROI while studying the energy cost of producing fuels from fossil energy resources. Today there’s a growing literature applying the ROI framework to food production in modern food systems, and I applied it to national data in The Energy Cost of Food and to small farming systems in The Energy Cost of Local Food.

While monetary and energy ROI ratios can be useful metrics, I’ve come to believe that the ROI framework is much more broadly useful. I’m currently teaching a course on voluntary simplicity, and a recent homework assignment invited students to keep track of every penny they spend over the course of a week and to explore the many types of non-monetary benefits they get from that spending. Does the money spent on dinner with a friend have the added benefit of strengthening that relationship? Does the money spent buying food at a farmers’ market have the added benefit of providing access to higher quality food than one can get at a local supermarket? Does supporting farmers’ markets pay added dividends by creating a space for people to come together, have conversations they might not otherwise have and support the building of community more generally?

All of these non-monetary benefits are also returns on investment, but in a system measured solely by money they’re invisible. We all make decisions on what to spend our money – or other resources like time and effort – and I think we’d all do well to explore the many non-monetary costs and benefits that accompany this spending. Economists increasingly recognize the value of these ‘external’ costs and benefits within the context of ‘full cost accounting’, but this is rarely practiced outside academic circles and a few government agencies and non-profits. One of my goals in the voluntary simplicity course I’m teaching is to strengthen my students’ intuitive senses of the many non-monetary costs and benefits that tag along with different purchasing habits, so they can better link their purchasing patterns with their values and with the identity they’d like to cultivate.

Let’s play with this a bit. Think about the last item you bought. If you only looked at the monetary benefits you got from that purchase, would it deliver a positive ROI? If not, why did you buy it? What other benefits did you get from that purchase that might offset its lack of positive ROI from a strict money standpoint? What other costs might be associated with it that might offset some of those non-monetary benefits? How many hours did you have to work to earn the money you needed to afford that purchase? These are all useful questions, and they can help lead us towards habits that make the best possible use of our time, energy and resources.

Local Food: A Bridge to Somewhere?

MarketYears ago a dear friend who owned a vegetable farm became pregnant, and as her belly grew she found herself less and less able to keep up with her farm chores and, consequently, earn the meager living she’d come to depend on. As any decent person would, I teamed up with a few friends to take over the farm’s operations: planting, weeding, harvesting, washing, bagging and, most importantly, marketing the products every Saturday at the local farmers’ market. We handed every penny of the revenues to Amy, and although many years have passed I still harbor an incredible appreciation for the hard work that goes into producing fresh vegetables and will always have a soft spot for farmers’ markets and the hard working men and women who sell at them.

MarketDataThis past weekend, while wandering through my local farmers market – one perhaps a thousand miles from Amy’s land - I noticed how few and far between the actual farmers’ booths were. I succumbed to my geek-urge and collected some data: 52 booths featuring prepared or processed foods, 49 booths featuring local artisans selling their wares, and a scant 27 booths where farmers sold food or flowers grown on nearby farms [1]. When I first moved to my town about 7 years ago, farmers occupied most of the booths at the farmers’ market. Alas, those days are gone. Today, at my local farmers’ market, farmers are now a minority.

Most farmers I talk to – and I talk to plenty – are trapped between a rock and a hard place. They’re motivated by a love of working landscapes and lofty environmental and social ideals, but meeting these ideals requires them to charge far higher prices for their food than what consumers today are accustomed to. In Treating Food as an Investment I make the case for paying the higher price, but even as I happily shell out $5 for a pint of blueberries harvested the day before or $10 per pound for sweetbread from a grass fed bull I wonder whether markets are ready to bear the real cost of quality food [2].

During the comedy that was the 2008 US Presidential election, Vice Presidential candidate Sarah Palin was chided for supporting, then abandoning and finally mocking a project dubbed the “bridge to nowhere”. The proposed bridge would have connected the mainland Alaskan town of Ketchikan to its airport, which was built on an island, to facilitate easier access than the current ferries provided. The airport happens to be Alaska’s fourth largest as measured by passenger boardings, so the proposed bridge wasn’t really a bridge to nowhere, but once media caught onto that phrase they wouldn’t let go. Palin’s willingness to pander to political sentiment and abandon – and eventually mock – a project she initially supported didn’t do much for her public image, either nationally or in her home state of Alaska. I can’t help but think that hidden in Palin’s ‘bridge to nowhere’ fiasco are overarching lessons that leaders in the local food movement should be mindful of.

As I walk through my local farmers’ market and see heritage meats, heirloom vegetables and all sorts of ingredients fit for the menus of gourmet restaurants, I wonder what the point of the local food movement really is. Is it to make fresh, locally produced, healthy food available to consumers? If so, why are the number of farmers selling fresh, whole food dwindling at my farmer’s market? Why are booth spaces increasingly occupied by artisans selling wares that are intriguing but inedible, or by vendors selling high-priced, processed food that, as best I can tell, contributes to obesity, diabetes and other chronic diseases just as readily as the industrially produced junk that lines grocery and convenience store shelves across the country? Are changes at my farmers’ market exceptional? What value is there in celebrating locally produced junk food, and giving the vendors who produce it space at a farmers’ market? How can they be part of the problem, and part of the solution?

In the many documentaries and books that idealize the local food movement, a common thread is a vision of local food that gives people agency, that lets them take responsibility for their health in ways our nationalized or globalized food systems doesn’t. My fear is that if the local food movement strays too far from this mission of providing higher quality, healthy food, it risks being written off as another interesting fad that was co-opted by profit-seeking. If the local food movement can be thought of as a bridge, are its leaders and supporters willing to make sure the bridge leads somewhere useful?


  1. The term ‘nearby’ is relative; some of the vendors drive over 50 miles to attend this farmers’ market, as it gets a lot of visitors. Whether these farms’ food counts as ‘local’ is up for debate, but at least they’re farms that sell whole, unprocessed foods and not junk food vendors.
  2. ‘Sweetbread’, for those who are unfamiliar, is the commercial name given to an animal’s pancreas.