How to turn surplus summer veg into an easy ferment – recipe | Waste not

Like a kid in a sweet shop, I often get carried away at the market, especially with the abundance of this time of year, and usually end up leaving with far more vegetables than I have storage space for. By the end of the week, we’re inevitably left with a surplus that needs to be cooked or preserved.

Lacto-fermentation is a great way to preserve vegetables. It also, of course, diversifies our nutrient intake and boosts gut health via the beneficial bacteria that are created during the fermentation. This recipe is a wet fermentation, rather than a dry one such as sauerkraut; use it to ferment whole, sliced or chopped vegetables, all of them scrupulously cleaned.

Easy lacto-fermented summer vegetables

Today, I fermented a surplus of vegetables, including broad beans which I paired with lemon and dill, carrots that I brined with lemongrass and coriander seed, and aubergine with miso.

Wash, trim and slice or chop your vegetables to the desired size. Smaller vegetables such as broad beans, radishes and gherkins can be left whole, but you might prefer to slice an aubergine or dice kohlrabi, for example.

To prevent the vegetables becoming too soft, add a source of tannins to the jar – a vine leaf or raspberry leaf, say – and refrigerate after the fermentation is fully active and bubbling away. If they do get too soft, however, don’t worry: your fermented veg will still taste delicious. Use them much as you would miso paste, to add depth of flavour to dressings or stews (if the latter, add them at the end of the cooking process).

To help prevent any mould forming, make sure the vegetables are completely covered by the brine. If need be, use a fermentation weight or a clean, heavy, non-porous, non-metallic object to keep them submerged. Also, keep an eye on your vegetables while they are brining, and give them a stir every day or two. Once fermented, store in the fridge so they keep for longer.

To sterilise a jar, wash it in very hot water, then place on its side in a cold oven. Turn on the oven to 150C (130C fan)/300/gas 2, then turn off once it reaches temperature. Leave the jar in the oven until needed. To sterilise the lids, bring to a boil in a saucepan of water, then leave them in the water until required.

400g vegetables – eg, aubergine, broad beans, carrots
12g sea salt
1 herb sprig – eg, sage, basil, thyme (optional)
3cm piece citrus zest (optional)
1 garlic clove , peeled (optional)

Tightly pack your chosen vegetables into a sterilised 500ml jar, leaving a 3cm gap at the topCut the vegetables, if need be, to fit them all into the jar: I like to leave them whole where possible, or cut them into long, thickish sticks. Add any of the optional aromatics.

Make a 3% brine solution by stirring the sea salt into 400ml water, ideally filtered. When the salt has dissolved, pour the brine over the vegetables until they are submerged. Cover loosely with a lid or a piece of cheesecloth and leave to ferment at room temperature and out of direct sunlight for at least four days, or until the mix turns effervescent and lively. Stir the mix every day or two.

You can now either leave the jar at room temperature to continue fermenting, or seal and put in the fridge, which will halt the fermentation process. Vegetables in brine are at their best consumed within one month.

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