Dry-salted - Europe and North America

Sauerkraut

Name: Sauerkraut
Cuisine: Europe and North America

The bulletin's account of sauerkraut is a description of a process rather than a list of instructions, so this page is short and the numbers under it are doing most of the work. It is the fermentation the rest of the bulletin measures everything else against.

6 steps, every one quoted from FAO Bulletin 134 5.6.2. The step labels are this site's; the sentences under them are not.

Salt, at a batch you might actually make

2.0 to 2.5 % w/w, of the weight of the vegetable.

Vegetable	Salt at 2%	Salt at 2.5%
1 kg	20 g	25 g
2 kg	40 g	50 g
5 kg	100 g	125 g

The arithmetic, at 2 kg

salt = vegetable weight x percent / 100
     = 2.000 kg x 2.00% / 100
     = 40.0 g

Total after salting: 2.040 kg.

This is a percentage of the vegetable, not of the finished brine. The two conventions differ, and the calculator sets out by how much.

Every number the source states

Salt, final concentration: 2.0 to 2.5% w/w
Salt added as: 1 to 1.5 kg per 50 kg cabbage (2 to 3%)
Fermentation temperature, optimum: 21°C
Temperature for initiating fermentation: 18 to 22°C
Terminal acidity, as lactic acid: 2 to 2.5%
Microbial succession: Leuconostoc mesenteroides, then Lactobacillus plantarum and L. cucumeris, then L. pentoaceticus
On brine: Dry salt, not brine

Substrate

Cabbage

Region

Method

Numbered for your place in the list. Every sentence below is the source's own, verified against the page it came from when this table was last built from the sources.

Shred and salt
Shredded cabbage or other suitable vegetables are placed in a jar and salt is added.
Press
Mechanical pressure is applied to the cabbage to expel the juice, which contains fermentable sugars and other nutrients suitable for microbial activity.
Keep it under
An insufficient level of juice to cover the kraut during the fermentation allows undesirable aerobic bacteria and yeasts to grow on the surface of the kraut, causing off flavours and discoloration.
Hold the temperature
A temperature of 18° to 22° C is most desirable for initiating fermentation since this is the optimum temperature range for the growth and metabolism of L. mesenteroides.
Wait for the succession
The activity initiated by the L. mesenteroides is continued by the lactobacilli (L. plantarum and L. Cucumeris) until an acidity level of 1.5 to 2% is attained.
Finish
Finally, L. pentoaceticus continues the fermentation, bringing the acidity to 2 to 2.5% thus completing the fermentation.

What else the source says

Why the salt is there: The principle function of salt is to withdraw juice from the cabbage (or other vegetable), thus making a more favourable environment for development of the desired bacteria.
Why it is the acid and not the salt that preserves it: The spoilage organisms can tolerate salt concentrations up to between 5 and 7%, therefore it is the acidic environment created by the lactobacilli that keep the spoilage bacteria at bay, rather than the addition of salt.
Why a few degrees matter: A variation of just a few degrees from this temperature alters the activity of the microbial process and affects the quality of the final product.

What is doing the work

Before you make this

This site is a reference and not a food safety authority. It reports what named sources published and does not certify that any preparation is safe. The safety page sets out what the sources themselves say about acidity, about surface growth and about when to throw something away, and equipment lists the instruments the numbers above cannot be checked without.

The full record for this pickle, including every source consulted and the ones that disagree, is on its tradition page.

Other dry-salted recipes

Method and asides from FAO 134 Battcock, M. and Azam-Ali, S. (1998) Fermented fruits and vegetables: A global perspective. FAO Agricultural Services Bulletin No. 134. Food and Agriculture Organization of the United Nations, Rome. Numbers from the same source, extracted separately and listed on methodology.