The two approaches

Dry salting draws moisture out of the vegetable through osmosis, creating a naturally salty liquid that surrounds the produce. Brine salting — submerging produce in a prepared salt solution — gives more predictable salt concentration and is preferred when large quantities need uniform results.

Both methods, when salt concentration is sufficient, inhibit the growth of harmful bacteria while allowing Lactobacillus species — naturally present on vegetable surfaces — to ferment sugars into lactic acid. This acidification further preserves the product and produces the characteristic sharp flavour of Polish kiszonki.

Salt selection

The type of salt used affects both the process and the final product. Polish household tradition favoured coarse non-iodised salt (sól kamienna or sól morska niejodowana). Iodised table salt is not suitable for fermentation: iodine is an antimicrobial agent that suppresses the Lactobacillus cultures needed to drive fermentation.

Finely ground salt dissolves faster and can produce uneven initial distribution when used for dry salting. Coarse salt applied in layers distributes more evenly as it draws out moisture.

Ogórki kiszone — fermented cucumbers

Cucumbers destined for fermentation should be picked small (10–12 cm), harvested in the morning, and processed the same day. Cucumbers that have been refrigerated or left for more than 24 hours after picking ferment less predictably.

Brine concentration

A standard brine for cucumbers uses 20–30 g of non-iodised salt per litre of water. The lower end of this range produces a more active ferment and a softer final texture. The upper end slows fermentation and results in a crisper product — appropriate if extended storage is the goal.

Practical note: Dissolve salt in a small amount of boiled water, then add cold water to reach the desired volume. Using fully boiled water that has not cooled kills the lactic acid bacteria on the cucumbers. The brine should be at room temperature or cooler when poured.

Packing and additions

  • Pack cucumbers vertically in sterilised glass jars or a ceramic crock.
  • Additions that appear consistently across Polish recipes: fresh dill heads (not dried), a few cloves of garlic, horseradish root or leaf, and optionally a small dried chilli or two black peppercorns.
  • Horseradish leaf placed on top of the cucumbers helps keep them submerged and contains tannins that contribute to firmness.
  • All produce must remain submerged under the brine. Use a small plate or stone weight if needed.
  • Cover loosely — not airtight — for the first 2–3 days to allow CO₂ produced during active fermentation to escape.

Fermentation timeline

At room temperature (18–22 °C), active fermentation lasts 3–5 days. Small bubbles are visible through the jar glass. After this phase, transfer to a cooler location (cellar at 8–12 °C) to slow fermentation and preserve the product. Cucumbers are edible from day 3 but develop fuller flavour over 2–3 weeks.

Kapusta kiszona — sauerkraut

Kapusta kiszona is made by dry salting. Shredded cabbage is mixed with salt, which draws out juice over the course of several hours. The cabbage then ferments in its own liquid.

Procedure

  • Use firm white cabbage (główkowa). Remove outer leaves but set a few aside for covering.
  • Shred finely — 2–3 mm — using a knife or mandoline. Grate carrots and mix in if desired (1 medium carrot per kilogram of cabbage is a common ratio).
  • Weigh the shredded cabbage and add 20 g of non-iodised salt per kilogram.
  • Knead and squeeze firmly for 10–15 minutes until the cabbage releases significant liquid. This step cannot be shortened — mechanical action breaks the cell walls and accelerates liquid release.
  • Pack tightly into a clean crock or large glass jar, pressing down after each addition to remove air pockets. The cabbage should be covered by its own liquid by the end of packing.
  • Cover with reserved outer cabbage leaves and weigh down.

Fermentation at room temperature takes 3–7 days depending on ambient temperature and cabbage sugar content. Taste daily from day 3. Transfer to cold storage when the sourness is at the desired level — fermentation slows considerably below 10 °C but does not stop entirely.

Salted mushrooms

Mushroom salting uses higher salt concentrations than vegetable fermentation — the goal here is preservation rather than active fermentation. Wild mushrooms collected in Polish forests (particularly Boletus edulis, Cantharellus cibarius, and Lactarius deliciosus) are the traditional subject of this process.

Blanch whole or halved mushrooms for 3–5 minutes before salting to reduce volume and soften texture. Layer with non-iodised salt at 100 g per kilogram of mushrooms. Cover and store under weight in a cold location (4–8 °C). Mushrooms are ready to use after 4–6 weeks and keep for several months.

Rinse before use — the salt concentration in the final product is not suitable for direct consumption.

Further reading