In Orange County, North Carolina we take well-deserved pride in our local food web. We have innovative local farmers, numerous farmers markets and a host of local restaurants committed to using fresh, local ingredients. But we can, and should, keep striving for improvements. My recommendations for how we might do so, as you might expect, rely on a scientific perspective. To keep to my be-able-to-read-Common-Science-during-one-cup-of-coffee rule, I’ve broken the story into two parts. This week I will review the science and the first half of my recommendations. Next week I will finish my recommendations and conclude with a little dream of mine on how to help my recommendations comes to life.
Although I will be drawing on a number of sources for this analysis, I should note that I will be relying heavily on Cooked: A Natural History of Transformation, by Michael Pollan. So, let me start with an extremely short summary of this excellent book. Cooked begins with an explanation of the key shortcoming of a raw food diet. If you limited you diet to just raw fruits, vegetables, and nuts you would expend a lot of time and energy chewing. Further, due to the large size and complex structure of many of the molecules in raw foods, your digestion process would not be able to access all of the nutrients contained within. Cooking, which Pollan defines as being the transformation of raw foods through either the use of heat or the use of microbes as in fermentation or cheese making, improves food in two essential ways. First, the process of cooking foods breaks down some of their complex molecules such that your digestion process will require less energy and more efficiently extract nutrition. Further, chemical reactions that occur during cooking create new and beneficial compounds that were not present in raw foods. Many scientists and anthropologist believe that it was the invention of cooking, with its attendant enhancements of foods, that allowed humans to become the dominant species on Earth. With that background in hand, let me walk you through how I think we can utilize science to improve our local food web.
Bread has developed a reputation as being a source of empty calories. To a large degree, this reputation is well deserved, but it need not be that way. The nutritious parts of wheat are the bran and the germ. Unfortunately in nearly 100% of flour produced today, some or all of the bran and germ has been removed. Removing the bran and germ makes the flour white and gives it long shelf life. If you make bread from freshly ground whole wheat that still has the germ and bran, it is a very nutritious food. In fact, there were periods of time in Middle Ages Europe were over half all food calories consumed came from bread made in this manner.
We could make this sort of nutritious bread locally with a little cooperation. First, we would need some farmers to commit to growing types of wheat which are good for bread making and which have a variety of harvest dates throughout the year to provide a steady supply. Next, we would need to have someone, an entrepreneur, a co-op, or a government agency, operate a grain mill on a make-to-order basis for local bakeries so that the flour could be baked before it began to spoil. The mill would need to operate rather slowly with good heat removal. If you mill wheat too quickly, you create too much heat from friction that will spoil the germ. Spoiled germ gives off an unpleasant odor. The need for a wheat miller to monitor for this odor is the basis for the phrase, “keeping your nose to the grindstone.”
Lastly, we as a community, would need to commit to purchasing bread that have less shelf life than Wonderbread®. This would require us to make bread purchases at shorter intervals. We’d have better bread and better health.
We tend to think of fermentation as being the process by which yeasts convert sugar to ethanol in beer and wine. However, the definition is much broader than that. A definition of fermenation from thefreedictionary.com that I like is “Any of a group of chemical reactions induced by microorganisms or enzymes that split complex organic compounds into relatively simple substances.” Fermentation of foods by microorganisms enhances its value in three important ways. It increases the amount of nutrition that we can extract from foods. It drastically increases the shelf life of foods without the need for energy-intensive heat-based cooking or refrigeration. Lastly, the bacteria that we consume along with fermented foods are good for our health.
Let’s explore fermentation a bit further using cabbage as an example. (Disclaimer: I really love cabbage.) I like shredded cabbage in my salad. However, it there is too much, it can be hard to digest which results in our bodies not fully utilizing its nutrients along with some odd gurgling noises from our abdomens. The nutritional value of cabbage and the ease with which we can digest it can be enhanced either by cooking it or fermenting it to make sauerkraut.
Making sauerkraut is easy as long as you have patience. All you need to do is cut up some cabbage, immerse it in a dilute salt-water solution, and put it in a container that has an air lock, typically a U-trap filled with water. This keeps air from the outside from entering but allows carbon dioxide and other gases produced during the fermentation process to escape. The bacteria that carry out the fermentation will have been present on the cabbage when you started. For the first couple of weeks you will notice bubbles coming out through the air lock letting you know that bacteria are fermenting away. Once they stop, you can remove the air lock and seal the vessel. Over the next couple of months, a class of acid-producing bacteria from the genus lactobacillus acidophilus will become dominant by making the sauerkraut too acidic for other species to survive. When you get to this point your sauerkraut is finished.
Lactobacillus acidophilus are the predominate type of bacteria in the human mouth, gastrointestinal tract, and vagina. They perform the similar functions in the human body as they do in the sauerkraut by outcompeting other species which could potential be harmful to you. When the population of lactobacillus acidophilus within the body is reduced by the use of broad-spectrum antibiotics other the populations of problematic bacteria can grow and cause problems such as gastrointestinal distress or vaginal yeast infections. This is why your doctor may suggest that if you are on antibiotics that you should eat yogurt, which contains lactobacillus acidophilus for the same reasons as sauerkraut.
Unfortunately, within our current food culture in the U.S., yogurt is just about the only live-culture food which is available. However, we could easily have many more. Essentially any vegetable can be fermented in a similar manner to what I described for cabbage. You can add some vinegar and species to get a pickled flavor. However, pickled vegetables in the grocery store have all been heat pasteurized to kill off all bacteria, beneficial and otherwise, before we eat them.
From a local perspective, we would be well-served to adopt more fermented foods. Individuals can preserve foods at home this way. (I have some sauerkraut that I plan to sample over Thanksgiving.) But a more interesting approach would be to try something on a larger scale. Consider what happens to unsold vegetables at a farmers market. Some are donated to local food kitchens, which is wonderful. However, I suspect that much of it ends up being wasted. Imagine a situation where we created a fermentation co-op where these unsold vegetables were preserved and enhanced through simple, low-cost fermentation. This could enhance the profits to local farmers, reduce food waste, and provide a wider range of live-culture foods to our community. It’s a clear win-win-win.
Next week I’ll review two more recommendations and then tell you about my dream to help make it happen. See you then.
Jeff Danner talked about this week’s column with Aaron Keck on WCHL.
Have a comment or question? Use the interface below or send me an email to email@example.com. Think that this column includes important points that others should consider? Share a link to this column on Facebook or Twitter. Want more Common Science? Follow me on Twitter on @Commonscience.