My favorite type of pickling is lacto-fermentation, where bacteria break down sugars and produce lactic acid. These bacteria are not only incredibly healthy (they’re the same type that folks eat Greek yoghurt for) but they also add flavour to the food. It’s been a while since I’ve done any pickling, and I believe the last time was when I made corned beef right when I first started this blog.
Let’s start with a bit of biology. Normally, when critters, including us, use sugar for energy they need to take in oxygen to use in the reaction, and produce carbon dioxide. When the oxygen supply is cut off, the process comes to a screeching halt. For some organisms, lack of oxygen is no problem because they use a process called fermentation, which is simply the breaking down of sugars without using oxygen. We can use fermentation for short periods of time, when we are using lots of energy (say while sprinting) and can’t take in enough oxygen to supply all of the energy we need.
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Yeast performs one of the best-known forms of fermentation. They break down sugars and release ethanol (alcohol) and carbon dioxide. For obvious reasons, this is called ethanol fermentation. Lacto-Fermentation, or lactic acid fermentation, is similar, except that the byproducts are lactic acid and carbon dioxide. This is the type we use when we sprint. Lactobacillus, the bacterium that makes yoghurt, also uses this reaction.
To begin with, I built a new fermentation bucket. This is a food-grade two-gallon bucket with an airlock in the lid. The airlock allows carbon dioxide to leave the bucket, because the lid would pop off if the gas built up pressure inside. It also prevents oxygen from the outside air from entering, because as we covered, fermentation only occurs when there is no oxygen available.
We shredded six onions, three red and three white. I used this ratio before and liked the result, so I’m sticking with it. Using a mandolin makes the process quick and easy. Here’s Ace slicing onions.
In the meantime, I prepared three quarts of brine. I got the salt/water ratio from this website, except that I used ice cream salt for one of the quarts and sea salt for the rest. The reason to use salt is that we don’t want ethanol fermentation in this recipe. Yeast is killed by salt, while Lactobacilli thrive in it. This is a simple way of selecting which form of fermentation we want. You can add spices, but I prefer not to, so that I can use the onions in any recipe I want.
The onions go into the bucket and are covered with brine. To keep the onions submerged, place a plate over he onion and press down. It is important to keep the onions submerged to keep it from spoiling. Next, place the cover tightly on the bucket, and let it stand.
The process can take over a month, so I will check on it every now and again. The easiest way to see that the reaction is occurring is to watch the airlock. If air is bubbling out you know that there is fermentation occurring.
~The Homesteading Hippy