Last summer, lurking in a corner in the dark of my basement was a vat of tiny warty cucumbers from our garden, now drowning in a salty brine of peppercorn, dill, garlic and grape leaves. It was my first ever experiment in fermentation. I faithfully checked the vat daily, ensuring the vegetables stayed submerged below the brine-line and to skim any scum from the surface where the saline content wasn’t high enough to prevent undesirable microbial growth.
After about three weeks, when the lactic microbial organisms - the same little guys that curdle milk - converted the natural sugars into pleasantly sour lactic acid, I could finally begin to eat them. Brining and pickling have been used for centuries as a simple and effective methods of food preservation. So why did it make me so nervous?
This is why. I had my doubts, last summer, as to whether after three weeks I really would get pickles, or be ingesting a three-week bubbling slop of garlicky cucumber slush. And is there really even a difference between putrid cucumber cadavers and what we call a pickle? The whole process, as ancient as it is, seems so Frankensteiny.
This is the rub with fermented foods. The lines between “fermented” and “rotten” are fairly fuzzy. We generally consider foods that have undergone intense microbial action as rotten, and for good reason. Some of those microbes make us sick and could in fact kill us. On the other hand, the right foods combined with the right microbes produce complex flavor, provide a desirable texture and preserve nutritional content. They are in fact, delicious.
We humans are hard-wired to keep undesirable microorganisms out of our bodies. But the truth is, you probably eat fermented foods all the time - and enjoy them. Cheese and yogurt are two delicious examples. Bread, too, is the product of microbial action. Our bodies need microorganisms, inside and out, to be healthy and happy. What that disgust trigger in your brain doesn’t know is the difference between the good microorganisms and the bad ones.
I taught my brain this difference in preparation for the pickle tasting last year. If I had been born 100 years ago, I wouldn’t have needed to research this topic. There would be a vat of briny veggies fermenting in their own juices in every basement. We’d be depending on them to survive and fortify our bodies with vitamins during the long winter months. But food production and interaction has been so far removed from the home in this day and age, this process has become foreign. Our culture is obsessed with hygiene so that even the mention of bacteria in food gets people’s brains on the alert. So my brain got schooled. This is what it has picked up so far:
The main difference between rotten vegetables and those that are fermented is salt, according to Sandor Katz in his book Wild Fermentation. Salty water, or brine, serves as protection against the growth of putrefying microorganisms and favors desired strains called Lactobacilli. Most fermentation involves a succession of several different microbial species, each one altering the environment to make conditions more favorable for the next.
The environment in my pickle vat started by acidifying rapidly, to the point that it became impossible for bacteria responsible for food spoilage to take over. Vegetables preserved this way can stay edible in a cool place for many months. This is the same process that gives sauerkraut its vinegary crunch.
There are other good things that happen in this process. Fermentation can break down nutrients into more digestible forms or create antioxidants and omega-3 fatty acids, both good for you. It can also, to some degree, supply your digestive tract with cultures you need to break down other foods and absorb nutrients.
And - get this - certain kinds of bacteria in your gut, the kind you find in some fermented foods, can have a positive effect on your brain, according to study in the British Journal of Nutrition. My brain is more interested in taste than bio-chemistry, but it doesn’t hurt to be informed.
For now, I’ll keep skimming scum, quieting the disgust mechanism in my brain, and hoping for more positive microbial action in the basement.