Fermenting Vegetables in New Zealand

Fermenting sours vegetables with salt and the bacteria already on them. Sauerkraut has a tested method; most other home ferments do not, so start there.

The tested method

USDA's sauerkraut uses 3 tablespoons (45 ml) of pickling salt for every 2.25 kg of finely shredded cabbage, packed down until its own juice covers it and kept 2.5 to 5 cm under the brine. At 21 to 24°C it is ready in 3 to 4 weeks; at 16 to 18°C, 5 to 6 weeks. Below about 15°C it may not ferment at all.

Winter is the hard part here

Cabbages are ready when New Zealand houses are coolest. A cupboard near the hot water cylinder or a heated room often gives the steady warmth kraut needs; check it with a thermometer, because above 24°C kraut softens. In an unheated Otago or Southland room in July, expect a stalled ferment.

Keeping it safe

• Measure the salt and do not reduce it
• Keep everything under the brine with a plate and weight or a sealed bag of brine
• Skim surface scum as it forms
• Throw out kraut that is soft, slimy, dark or smells rotten

New Zealand Food Safety asks for extra care with fermented meat and fish. Kimchi and brined vegetables are popular, but we have not found a tested method from a food safety agency, so we do not give recipes. Full method: sauerkraut guide.

Sources we checked (October 2026): New Zealand Food Safety (MPI), Clostridium botulinum or botulism; USDA Complete Guide to Home Canning (2015) through the National Center for Home Food Preservation: Sauerkraut, General Information on Fermenting.