How Does Lacto-Fermentation Work? The Basics for Pickles

How does lacto-fermentation work?

Lacto-fermentation is a natural process that uses beneficial bacteria to preserve food. Here's how it works: when vegetables are submerged in a salty brine, the lactobacillus bacteria present on their surface begin to convert sugars into lactic acid. This acid acts as a natural preservative, giving fermented pickles their distinctive sour taste and crunch.

What do you need to get right when fermenting?

Three things: clean equipment, non-iodised salt, and keeping everything under the brine.

• Cleanliness is crucial. Ensure all your equipment and jars are thoroughly cleaned and sterilised.
• Use non-iodised salt. Pickling salt or sea salt is ideal, as iodised salt can inhibit the fermentation process.
• Keep it submerged. Vegetables must stay fully submerged in the brine to prevent mould and spoilage.

How long does fermentation take?

It depends on the vegetable and how tangy you like it. In the book, kimchi ferments at room temperature for 3-7 days, radishes for 5-7 days, and sauerkraut for 1-4 weeks. Once it reaches your desired level of tanginess, seal the jar with a lid and store it in the fridge.

Do fermented pickles need vinegar?

No. In lacto-fermentation the lactic acid made by the bacteria does the preserving, so the brine is just salt and water - or, for sauerkraut, the cabbage's own juices.

What is the difference between pickling and fermenting?

Pickling in vinegar preserves food with acid you add; fermenting lets good bacteria make the acid for you. Vinegar pickles are ready sooner and taste sharp and clean, while ferments take longer and develop a deeper, more complex sourness.

Why do you cover a fermenting jar with a cloth?

Fermentation produces gas. Cover the jar with a cloth or a fermentation lid to allow the gases to escape, and seal it with a normal lid only once it has finished and is going into the fridge.

Is cloudy brine normal when fermenting?

If fermenting pickles, a little cloudiness is normal. However, if it is accompanied by an off smell or slimy texture, discard the batch.

What should I do if I find mould in my pickles?

If you find mould in your pickles, it’s best to discard the entire jar. Mould can indicate contamination and potential spoilage.