Expert guide to fermenting

The pickles you buy from the shop aren’t fermented and they are essentially devoid of life because they are preserved in vinegar and pasteurised to kill any bacteria that might make them dangerous.

This is effective for preservation because food can be stored for years without spoiling, but it doesn’t have the same power as a wild brine ferment. The flavour is very different – the sourness comes from vinegar and sugar rather than from gut-healing lactic acid.

It’s easiest to ferment at home with familiar vegetables. Try carrots, green beans and cauliflower florets. They taste pleasantly sour, remain crunchy and their colour stays bright.

They are perfect for a quick pickle as they’ll ferment in about four days – and once done you can pop them into the fridge for eating any time. Brine fermenting is always best with firm vegetables. Chlorophyll-rich vegetables, such as kale and spinach, very seedy or soft vegetables are all best preserved by other methods.

FERMENTING EQUIPMENT

A simple thick jar with a lid will do. I prefer to use an air-lock, but a flip-top jar would also work because it releases some gases.

If using a flip-top or normal screw-top jar, let the gas out by opening it quickly every day or so. Whatever you use, make sure it’s clean – a wash in the dishwasher followed by some boiling hot water swished around will do fine.

Sometimes the vegetables float to the top and attract yeast so find a good system to hold them all down – you could use a cover or ‘follower’ like half a red onion, a crab apple or a vine leaf and then a light weight.

Or, push all the veg in so tightly that they are held down under the brine and don’t need a weight. It’s important to make sure the brine covers them completely though.

SALT FOR FERMENTING

I prefer finely ground sea salt and in the case of a brine you need enough for a 3%-5% solution. Too much salt will inhibit the lactic acid bacteria and stunt the ferment.

Use the following ratios for quick reference:

2% brine – 1 tbsp sea salt/1 litre of water

3% brine – 1.5 tbsp sea salt/1 litre of water

4% brine – 2 tbsp sea salt/1 litre of water

5% brine – 3 tbsp sea salt/1 litre of water

It’s best to start with filtered or unchlorinated water. If you use tap water, boil it first then cool it to room temperature before adding to the vegetables.

SPICE FOR FERMENTING

Try to stick to no more than three different herbs and spices that generally go together and be careful not to add too much. The vegetable you are brining is going to get sour and you won’t want it overwhelmed with garlic, for example.

When you add fresh herbs like coriander and dill stick to the root or stem part, this holds all of the flavour and won’t get slimy. Don’t crush spices, keep them whole to limit mould. The amounts you’ll add depends on the jar size, of course, but it’s better to be subtle than overbearing.

A good combination is a herb, one or two seeds and an allium, for example:

• Garlic, chilli and black pepper

• Dill, mustard seeds and garlic

• Lemon rind, garlic and chilli

• Lemongrass, coriander seeds and chilli

• Mustard seeds, chopped shallot and a sprig of thyme or tarragon

• Dill and parsley root, fennel seeds and orange zest.

Dill pickles

It’s best to use small, thick-skinned, gherkin-style ridge cucumbers for this. A very important ingredient for keeping them crisp is tannin – we use fresh grape leaves, which you can buy dried from souschef.co.uk – or a pinch of tea leaves, raspberry, blackberry or oak leaves work, too. If you have enough, put one on the bottom and then use another to hold the pickles under the brine before adding a weight and sealing the vessel.

Click here to get Sharon Flynn's recipe for dill pickles

Ferment for Good | Sharon Flynn (Hardie Grant)

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