How to make sauerkraut, a simple guide

What is Sauerkraut?

Sauerkraut is fermented shredded cabbage with a tangy, salty flavour. Due to the fermentation process it undergoes, sauerkraut offers nutrition and health benefits far beyond those of fresh cabbage. It is a great source of beneficial vitamins and probiotics that promote healthy gut bacteria, aiding in digestion and nutrient absorption.

Fermentation starts when naturally present yeast and bacteria, come in contact with the sugars in the cabbage. This needs to occur in an environment where there is no oxygen, fortunately that's easy to do when making sauerkraut.

Many store-bought sauerkrauts are made with vinegar, contain preservatives and sugar. They are often pasteurised, to stop the fermentation gasses being made, unfotunatelly killing the beneficial bacteria.
To make sure you get the health benefits of eating sauerkraut, you can make it yourself, giving you control of the tanginess and flavour.
It is easy to do, inexpensive, using locally sourced produce and wonderfully sustainable.

All you need is cabbage, salt and water

It is important to use a salt that is iodine and preservative free - natural sea or rock salt is preferred. Avoid using chlorinated water to make the brine, as it can inhibit the work of the beneficial bacteria. You can use boiled water that has been left in an open bowl overnight for some of the chlorine to evaporate.
For more information see our blog on Salt.

Method

Before you start making your sauerkraut, make sure all your utensils are very clean and sanitised, with hot soapy water, put through the dishwasher, or use sanitising solutions.

Select a cabbage that is fresh as possible and tight, an old cabbage won’t produce much juice, but it will still be usable. Any variety of cabbage can be used to make sauerkraut, green cabbage being the most traditional.

Remove the outer leaves and discard. Leave one clean whole leaf aside to make a lid to cover the shredded cabbage later.

Calculate how much salt to use

You will be adding 2% salt by weight.
To calculate the amount needed, first weigh the cabbage you are going to use, in grams.
Then divide the weight of the cabbage by 100, then multiply the answer by 2.
This will give you the number of grams you need to add to that weight of cabbage.

Shred the cabbage into thin uniform strips, then place in a large bowl and sprinkle with number of grams of salt you calculated that you need to give 2%.
With clean hands, massage the cabbage or use a tamper to crush the cabbage pieces. This will draw out the moisture. The liquid that comes out of the cabbage mixes with the salt, to make salty cabbage juice, this is called the brine.

If you want to add extra flavours

It’s not necessary, but herbs and spices can be added now for extra flavouring: garlic, ginger or pepper. Some traditional additions are garlic, ginger, pepper, dill, carraway, juniper berries or celery seeds. Experiment to create your own unique flavour.

Now start tightly packing your jar with the cabbage a little at a time, squashing it down with your hand or a tampering tool as you add more. This will remove trapped air and further crush the cabbage. It is very important to make sure there are no air spaces, as this will make the sauerkraut spoil. Pour any liquid that is left in the bowl into the jar.

Cut the leaf that was put aside into a shape that fits in the jar, so it forms a neat fitting lid for the cabbage, so that no small pieces float to the top and become exposed to the air.

Place a weight on the cabbage lid. You can use a fermentation weight, a sanitised smooth rock, a glass jar filled with water or a plastic bag with water in it. This is to keep all of the sauerkraut submerged under the brine, as it is important that the cabbage does not come in contact with the air, or it will be spoiled by the growth of oxygen-loving moulds and unfavourable bacteria.

Cover with a tight fitting lid with an airlock in place. The airlock promotes favourable conditions for a successful ferment. See our blog on air-locks.
If you aren’t using an air-lock lid, the jar must be opened, at least once a day to release the build-up of pressure made but the fermenting process, this is called burping. If the build-up of gasses can’t escape, the jar will crack or explode.

Leave the jar overnight and more water will be drawn out of the cabbage. You might need to push the cabbage down if it has risen a lot by using the tamper or a large spoon. A cabbage grown in warm weather, or one kept in storage for a long time might not give up much moisture, so a little brine can be made to top up the jar so the liquid is a few centimetres above the cabbage.

To make a 2% brine

Add 5g of salt to 1 cup of chlorine-free water, and stir until dissolved.
Pour enough of the brine into the jar so there there is about 2cm of liquid above the top of the cabbage.

Leave the sauerkraut to ferment in a cool dry place.
After 4 to 5 days the pH should have dropped to below 4, due to the creation of lactic acid. It should have a slightly sour smell and taste, but if it doesn’t, then leave to ferment a few days longer.
Now it is ready to eat, or it can be left for a few more weeks to develop a tangier and softer texture and flavour profile.
When you are satisfied with the flavour it can be put in the fridge to slow down the fermentation. The airlock is no longer needed as it will not be producing gas. Instead, cover with a tight fitting lid. It will last for 6 months in the fridge.

Enjoying your sauerkraut

The sauerkraut can be enjoyed as a side dish just as it is, added to salads, sandwiches, hamburgers or potato salad. The sauerkraut can be cooked with apple, corned beef, pork or smoked sausages. Sauerkraut is used to make cooked meals such as Polish Bigos stew, or German Sauerkraut, apple and bacon. When cooking the sauerkraut, the living probiotic bacteria is killed, but it is still a healthy nutritious meal to enjoy.