What is fermentation?
Fermentation is a method of preservation where, as mentioned, salt is used to extend the shelf life of what you have harvested. Salt is added to achieve a high salt concentration, which in turn promotes the lactic acid bacteria that already naturally exist in the food. The good bacteria thrive in the salty environment, but at the same time, the environment in the container becomes unfavorable for harmful bacteria that do not like salt. Lactic acid bacteria are so-called good bacteria (probiotics). They thrive and grow in anaerobic environments, that is, environments lacking oxygen, or in very oxygen-poor environments. Therefore, it is also important to remove as much oxygen as possible from the container to ensure a good fermentation process. We will explain how to do this with the example of sauerkraut below. But first, let's look at what you can ferment.
NOTE! Since you have not cooked the food when using this method, it is a living process that continues until you have finished what is in the container. Therefore, the containers must be stored cool, for example in the refrigerator.
What can you ferment?
Get started with fermentation
When you have harvested your vegetables and decided what you want to ferment, it's time to start. The process is almost the same for all foods, but varies slightly at the beginning depending on how you treat the particular vegetable. For example, you can shred cabbage, ferment whole cucumbers, and slice carrots. It also depends on how you will eat them later. But the more finely chopped the vegetables are, the more surface area good bacteria have access to, and the faster the fermentation process goes.The method basically involves adding 2-4 percent salt to your processed vegetables, ensuring that there is liquid covering them, and finally letting the container sit for a couple of weeks and "work."
The amount of salt needed depends on what you are fermenting. Foods that contain a lot of water, such as cucumbers, need more salt than vegetables that do not contain as much water. You weigh the vegetables you want to ferment, and then calculate how much salt is needed for the salt to make up 2-4 percent of the mixture.
But let's break it down into steps to give you a better understanding of how this is done in detail. In our example, we have chosen sauerkraut because it is one of the most common vegetables that are fermented.
You need this
- The vegetable you want to ferment
- Salt without iodine, preferably sea salt or Himalayan salt
- 1 large bowl
- Kitchen scale
- Glass jars to store the fermented product in (sterile)
Fermenting – step by step
Here we explain step by step, using sauerkraut as an example.
Prepare the jars: It's important that the jars you plan to store the food in are thoroughly clean, preferably sterile. Wash them properly. If they have a rubber ring on the top for extra sealing, this should be boiled.
Prepare the sauerkraut: Start by removing the outer leaves of the sauerkraut and make sure it's not dirty. Then, finely shred it, place the mixture in a bowl, and weigh it using a kitchen scale. If you're fermenting vegetables in chunks instead, you must weigh these along with the added water. The water should be enough to cover the vegetables with some margin when they're in the jar. You weigh both the water and vegetables together to get the right amount of salt in the next step.
Add salt: You should use two percent salt in the mixture. Calculate how much two percent amounts to based on the weight of your mixture. For example, if it weighed 250 grams, you multiply 250 by 0.02, and that will give you the amount of salt to add.
Massage in the salt: Sprinkle the salt over the cabbage mixture and begin massaging it so that the salt covers the entire surface. Continue until the cabbage starts to release liquid (starts to shed water). You'll see this as liquid begins to pool at the bottom of the bowl.
Pack the jar: Pack the jar full with the cabbage and liquid mixture. You do this by taking a handful of sauerkraut, placing it in the jar, and pressing it down as hard as you can. Press each batch to minimize air pockets – the cabbage liquid should form a layer on top. This reduces the risk of oxygen entering the jar.
Fill the jar adequately: Continue alternating between adding new layers and packing them down until about ¾ of the jar is full. You want some free space at the top to prevent overflow during the fermentation process.
Cover with a large cabbage leaf: Once you've packed all the cabbage and the liquid is on top, place a large cabbage leaf that covers the entire surface and press it down under the liquid.
Weight to hold everything in place: Place a weight on the leaf inside the jar. You can buy special preserving glass weights for this, or you can use a plastic bag filled with two percent saltwater, tied shut, and pressed down into the jar. This is because once the fermentation process starts, it will begin to bubble, and the gases will rise through the packed mixture. You don't want the mixture to rise above the surface, as this would cause your fermented sauerkraut to mold. The mixture should remain under the liquid.
Seal the jar: If you have a tightly sealed clamp jar, now place the rubber ring on it and close the clamp. If you have a jar with a screw lid, simply screw the lid on.
Protect the countertop: Since the process involves gas forming in the jar, it may overflow. Therefore, place the jars on a plate or in a bowl so that any overflow doesn’t end up on your countertop.
Store in a dark place: Let the jar sit at room temperature but ensure it's kept in the dark – for example, place it under a paper bag or a box.
Monitor the process: After a few days, the fermentation process will have started. You'll notice this by small gas bubbles rising along the side of the jar. If you don't see any, gently release the clamp and listen for a hissing sound.
"Burp" the jar: If you have a jar with a screw lid, you need to unscrew it every day to "burp" the jar, which means releasing some air so the pressure inside doesn't get too high. In a clamp jar, you don't need to open it, as these jars have a tab you can press down, and you'll hear the gas release.
Wait: Let the jar sit for a few weeks. How long depends on how sour you want it to be, but 2-3 weeks is usually sufficient. Taste it to see if you like the flavor, and let it sit longer if you want it even sourer.
Store in the refrigerator: Once it's ready, place the jar in the refrigerator. Let it mature for a few weeks before consuming; the flavor improves with some additional aging.
The fermented vegetables will keep for about a year. The shelf life, of course, depends on how well you've cleaned the jars and carried out the process above. The fermented vegetables can then be used for sausages, sauces, and other delicious dishes.