Homemade sauerkraut: green cabbage and carrot

Working with The University of Sheffield

Season: AutumnSpringSummerWinter

Many of us love having versatile cabbages in the veg box, but if you want to expand your cabbage repertoire we suggest making your own delicious, nutritious, organic sauerkraut or kimchi. The health benefits of ‘live’ fermented veg have been well documented: packed full of nutrients and good bacteria for a happy gut biome.

My own sauerkraut learning curve has been guided by a fantastic book: Fermented Vegetables by Kirsten & Christopher Shockey. Tastiest creations so far are cabbage kraut with lemon and dill, and swede kraut with orange zest, rosemary and black pepper.

Basic principles are wonderfully simple: shred vegetables and add salt, massage well so that the salt draws water from the veg to produce a brine. Pack the veg in a jar, keeping veg submerged in the brine using a weight. The anaerobic brine environment promotes the growth of healthy bacteria but inhibits the baddies. In 10 days or so, the friendly bacteria will have worked their magic and transformed the raw veg into tasty kraut.

I’ve set out the essential steps here for a simple cabbage and carrot sauerkraut. For a fuller understanding of fermentation processes, do consult a reliable source such as the Shockeys’ book. They have a website too ferment.works including a blog with advice and trouble-shooting tips. Make sure you read this one: Five ways to make sure you will not go wrong fermenting your veg.

And here’s a video: ‘Beyond Cabbage’ (forward to 13:30 for the demo if you’re in a rush).

How much salt? It depends on the veg weight. Organic veg box devotees know that we need to be flexible with recipe quantities! Let’s say use one large-ish organic cabbage and a couple of organic carrots. Once washed and prepped , weigh them to determine how much salt you need to generate a brine. The formula for the salt is 2% of the weight of the veg used.

Ingredients

EQUIPMENT:

Large chopping board

Large sharp stainless steel knife

Grater

Large non-plastic mixing bowl

Fermentation jar: a large kilner jar is good but large ordinary glass jars are fine too. The yield from 1kg of veg will be about 1.25 litres.

Fermentation weights - to hold the veg down below the brine level. Glass fermentation weights are a handy purchase if you want to get serious about kraut. You can also use a small lidded glass jar filled with water. This jar needs to fit fairly snugly inside the top of the fermentation jar.

Muslin cloth or clean tea towel

FOR THE KRAUT:

1 organic cabbage (large-ish if possible)

2 or 3 organic carrots

Unrefined sea salt - fine-crystal works well. Do not use table salt.

Caraway seeds - a generous pinch (optional)

Method

With very clean hands, prepare the veg. Remove the coarse outer leaves of cabbage. Rinse a few unblemished ones and set them aside. Rinse the rest of the cabbage in cold water. With a sharp knife, quarter the cabbage and remove the core. Wash and peel the carrots.

Weigh the cabbage and carrots and jot down the weight. Calculate how much sea salt you need: the basic formula is 2% of veg weight. 1kg of prepped veg needs up to 20g of salt. Be mindful that online conversions (grams to teaspoons etc) will depend on how large your salt crystals are.

Slice the cabbage quarters very thinly with a knife or mandoline, then tip the cabbage into a large mixing bowl. Grate the carrots and tip into the same bowl.

Add about three-quarters of the measured salt to the veg. With clean hands, massage the salt well into the veg for a few mins. Taste. You should be able to taste the salt without it being overwhelming. The veg will soon look wet and limp, and liquid will begin to pool as the brine is generated.

Mix in the caraway seeds if using. If you don’t see much brine yet, add the last little bit of salt and massage it in. Let the bowl stand (covered with a tea towel) for 40 mins or so and massage again.

Transfer the veg to the large jar, a few handfuls at a time, pressing down on the veg with your fist or a tamper (or a cocktail muddler) to work out the air pockets. You should see some brine on top of the veg when you press. Leave a couple of inches of head space above the veg in the jar.

If you still have enough veg left over in the mixing bowl, repeat process with another jar.

Top the veg in the jar(s) with one or two of the reserved outer cabbage leaves. Trim them with scissors if you need to. This ‘lid’ in direct contact with the veg in the brine is called a ‘follower’.

Weigh the follower down using a glass fermentation weight or a small sealed clean glass jar filled with water. Another alternative weight device is a ziplock plastic bag filled with water.

Set the jar aside on a small tray somewhere, out of direct sunlight, to ferment. Cover with a muslin cloth or clean tea towel. Let the veg ferment for 4 to 14 days. Check daily to make sure the veg are below the brine level, pressing down on the weight as needed - bubbles will rise to the surface.

Remember the golden rule: keep submerged in brine and all will be fine!

You can start testing the kraut on day 4. It’s ready when it’s nicely sour and pickle-y tasting, but not vinegary. The cabbage will be softened but has some crunch, and will be more yellow than green.

In our Sheffield climate, I’ve found that 10-14 days is ideal, depending on the season. It can take a bit longer in mid-winter. It also depends on whether you have central heating on etc.

When the kraut is to your taste, ladle it into smaller jars and tamp the veg down. Pour in any brine that’s left. Tighten the lids and store in the fridge. Kraut will keep in the fridge for 1 year.