Fermenting vegetables with Kate Harrison

Why ferment vegetables?

I began my journey with fermenting because I wanted another way to preserve the glut of vegetables coming from my plot in the late Summer and early Autumn. I’d already been making jams, pickles and chutneys, and I wanted to try something new.

Fermenting vegetables is also known as ‘lacto-fermentation’, because it uses lactobacillus bacteria. These bacteria are an example of the ‘good bacteria’ we hear so much about; they are good for your digestion and your gut health. They also help to preserve the good nutrients in your vegetables, such as Vitamin C, and break down some of the carbohydrates and proteins in food, making them easier to digest and absorb. Lactobacillus bacteria thrive in wet and salty conditions – the brine of your fermentation. They produce lactic acid, which is what gives all lacto-fermented foods that tangy sour fresh taste I find so delicious.

How to ferment vegetables?

Before trying my first fermentation, I went to a workshop run by Darren Ollerton of Alchemy Flow. In this workshop I discovered it was so easy, that I started my first ferment the next day. Darren is a fantastic educator and a great advocate for fermentation, and I recommend his website, his delicious products and his workshop. However, you do not need special training to make simple ferments like sauerkraut described below. It’s also much quicker than standing over a pan of bubbling chutney for hours on end – and the end result is sugar-free and more nutritious. Once you’ve tried this, you too will realise how simple it is, and you’ll start experimenting too!

Making sauerkraut

In its most basic form, sauerkraut is simply white cabbage, lacto-fermented with salt. Look for salt that has no added iodine, as it can interfere with the fermentation process. The lactobacillus bacteria is naturally present on the leaves of all vegetables – you are simply creating the salty conditions which encourage this good bacteria to grow, and which inhibits the growth of bad bacteria.

Use 2 to 3 tablespoons of salt for one medium cabbage (about 2 kg). This is not a precise art, and you can taste it to check it’s not horribly salty. I always like to add some caraway seeds to enhance the taste, about one tablespoon per medium cabbage. Once you understand the basic principle, you can start to add other spices and ingredients such as layering it with chard leaves or beetroot tops, adding garlic or spring onion.

Finely shred the cabbage, and put it in a container with lots of space to get your hands in. I use a clean washing up bowl.

Sprinkle the salt onto the cabbage, and stir and massage it in with your hands. Leave it for a while – between 20 minutes to an hour. You’ll find the salt is drawing the liquid out of the cabbage, creating a brine. Keep massaging the cabbage and moving it around, so all the cabbage has contact with the salty solution.

Sprinkle the caraway seeds onto the cabbage and stir and massage again to mix thoroughly.

Get a large jar, or a couple of medium sized ones, and firmly pack the cabbage into the jar. If the jar is big enough, you can get your hand in to really push the cabbage down, packing it tightly so there are very few gaps. You could also use a spoon or a pestle to do this.  The cabbage should be sitting in its salty brine. If you don’t have enough brine, you can always add a 5% salt solution to top it up.

Weight the cabbage down so all is submerged. I use a smaller jar filled with water as a weighting device. You can also use a clean plastic bag filled with 5% brine (in case it leaks), packed into the neck of the jar.

Cover with a clean tea towel or muslin and leave at room temperature for several days. How long is up to you, and the temperature in the room. It could be ready in four days, or you could leave it for two weeks or more. The longer you leave it, the sourer it becomes – so taste it occasionally to check.  Refrigerating the ferment slows the process down dramatically, so once you have the taste you like, keep it in the fridge.

Enjoy it as a pickle on the side of your plate, as an accompaniment to sausage and mash, in soups or sandwiches – experiment!

Once you understand the technique, you can try other things –  red cabbage sauerkraut, fermented runner beans and kimchi.

Troubleshooting

I promise you, making sauerkraut is easy! Here’s a few things to remember to prevent problems:

• Keep hands, utensils and jars clean. No need for sterile jars, but wash with hot soapy water and rinse well
• Not too much salt – this inhibits the fermentation process and tastes rubbish. If your mix tastes too salty, you could add a bit of water before starting the fermentation
• Not too little salt – this will mean the cabbage will rot instead of fermenting. You’ll know by the smell, and the mould. If your cabbage looks mouldy, or you have any doubts about it, throw it away and start again. Rinse before adding to your compost bin, to remove the salt.
• Be aware that fermentation creates a gas, carbon dioxide. This gas needs to escape during fermentation, so do not put a tight lid on your jar, or it may explode. It’s OK to use a lid once you’ve put your ferment in the fridge.

Find out more

Sauerkraut is just the beginning! Look online and you’ll find recipes for all sorts of vegetable ferments. You can also learn about kefir (fermented milk) and kombucha (fermented tea).

If you want to read more, in my opinion Sandor Katz is the best author on the topic: “Wild Fermentation” is the classic.

Kate Harrison is a BHOGG member and has gardened on the Weald allotment for 17 years. She is a member of the FareShare Sussex steering committee and is passionate about reducing food waste and helping more people eat healthy and nutritious food.