To start a batch of lacto-fermented vegetables, all you need are the vegetables, water and salt as well as a large jar with a wide opening.
The relationship water to salt is always the same: two cups (500 ml) of water to one tablespoon of salt.
The salt is needed to keep the pathological bacteria in check. It does not affect the good bacteria adversely. Once the friendly bacteria have gathered strength in numbers, the pathological bacteria can do them no more harm. The lactic acid formed in the process of fermentation eventually kills off the pathological or putrefying bacteria completely.
Lactobacillus can be found in abundance on the surfaces of all plants, especially those growing close to the earth. Your vegetables naturally come with them.
Use a large glass or ceramic jar—around two to three quarts (2 to 3 l) in size—with a wide opening.
any vegetable, cut into small, thin pieces
5 to 6 garlic cloves or a piece of ginger, peeled and cut into thick slices (optional)
a sprinkle of whole spice seeds such as caraway, fennel, mustard or cumin (optional)
a handful of fresh herbs like thyme, oregano, rosemary, sage or tarragon (optional)
6 cups (1 ½ l) water
3 tablespoons salt
1 Wash your jar with hot water and detergent and set aside.
2 Bring the water to a boil and add the salt. Stir to dissolve and let the mixture cool a bit. This is the brine.
3 Place the vegetables and the garlic, spices or herbs into the jar. Pack tightly, but leave about 2 inches (5 cm) at the top of the jar.
4 Cover the vegetables with the warm brine.
5 Cover the brined vegetables inside the jar with a plate small enough to pass through the jar opening. Press down the vegetables by placing a clean weight, such as a glass filled with water on top of the small plate.
6 Make sure the vegetables are always covered with the brine. If there is not enough brine to cover, boil some water, dissolve a proportionate amount of salt, cool the new brine to warm and then add it to the jar.
7 Place the jar into a bowl or deep plate to catch any brine that might spill over the rim during fermentation.
8 Cover the jar opening with a large plate or a kitchen towel. In the initial fermentation stage, the vegetables should be covered loosely to prevent dust or insects from falling into the mixture. But the jar should not be closed tightly so that any fermentation gases can escape.
9 Let the jar sit at room temperature for at least three days. Check once in a while to make sure that the vegetables are always covered with the brine, as lacto-fermentation is an anaerobic process. If vegetables float to the surface, mold can develop on them. Skim off and discard any foam that might form on the surface of the brine.
Carbon dioxide is released during fermentation. So the appearance of bubbles around the submerged vegetables is a clear sign that lacto-fermentation is indeed underway.
Taste the vegetables on the third day. If they taste pleasantly sour, close the jar with a lid and place it into the refrigerator. From my experience, vegetables taste just right after three to four days, but it all depends on the temperature in the room. The process might take a day or two longer.
Do not despair if the vegetables taste just salty at first. Be patient. With time, a lovely tartness will come to the forefront and the salty flavor will subside.
Some vegetables take longer to ferment than others. Beets take at least seven days, and cabbage takes from seven to ten days to become sauerkraut.
When you refrigerate your jar of vegetables, the lacto-fermentation does not stop but it slows down considerably. Do not discard the brine after you have eaten all the vegetables—it is loaded with friendly bacteria and enzymes. Drink it as an aperitif before your meals to enhance your digestive power. (I remember from my childhood in Germany that the health food stores sold bottled sauerkraut juice for that reason.) If you find the brine too salty, dilute it with some water.
Make it a healthy habit to have some form of raw lacto-fermented vegetables every day. A little goes a long way. A sensible portion might be two heaping tablespoons full. You can have them as an appetizer before your meal, as a little side salad, or as a snack in between.
More on the benefits of lacto-fermented vegetables here.