Which salt to use

Pure salt, with no iodine or anti-caking agents, and weighed. Pickling salt is the top choice; sea salt works if you weigh it, and low-sodium substitutes don't work at all.

6 min read First steps Reviewed October 27, 2026 24 facts, each with its source

The short answer

For fermenting you want salt with no additives¹ and no iodine, because iodine can interfere with fermentation². The top choice is canning or pickling salt: it has no impurities and an even grain³. If you can't find it, a coarse non-iodized salt does the same job⁴.

Put another way: look for a package whose ingredient list says only "salt." And whichever you pick, weigh it.

Salt by salt

Salt	For fermenting	Why
Canning or pickling	Yes, first choice	Pure, with an even grain⁵
Coarse, no iodine or anti-caking agents	Yes	The guides accept it alongside pickling salt⁴
Kosher	Yes, by weight, if the label says only salt	The guides describe it without anti-caking agents⁶, but some brands add them; and its grain is much bulkier
Sea salt with no additives	Yes, by weight	Its impurities vary and can affect the result⁷
Flake	Only if you weigh it	Its density changes from one package to the next⁸
Iodized table salt	No	Iodine and anti-caking agents⁹
With anti-caking agents	No	They cloud the brine¹⁰ and leave sediment¹¹
Low-sodium or substitutes	No	Fermentation needs sodium chloride¹²
Specialty: pink, black, smoked, with herbs	Better not	They may carry heavy metals or additives¹³

What about sea salt?

Here the sources don't say quite the same thing, and it is worth knowing.

A University of California Master Food Preservers guide accepts sea salt if you weigh it, with a caveat: its impurities vary a lot and can affect the result⁷. The BCCDC guide, written for businesses that sell ferments, advises against it along with iodized and specialty salts, because they may contain heavy metals, anti-caking agents or other substances that interfere with fermentation¹³. It adds a practical problem: the wrong salt can discolor the brine and mask spoilage¹⁴.

At Fervida we settle it like this. If you have the choice, use pickling salt or a coarse salt with no additives. If sea salt is all you have, pick one whose label says only "sea salt," with no iodine or anti-caking agents, and weigh it. Keep the colored salts for the table.

How to read the label

Before you buy, read the ingredient list, not the name on the package:

Only salt. That is what you want: "salt," "sea salt" or "sodium chloride," and nothing else.
Iodine, or potassium iodide or iodate. It is iodized salt. Fine for the table; not for fermenting.
Any anti-caking agent. That is what clouds the brine and leaves white sediment. Labels may name it (yellow prussiate of soda, sodium ferrocyanide) or, in Europe, give its E number, such as E535 or E536.
Potassium chloride. It is a low-sodium substitute. It doesn't work, and it tastes bitter¹⁵.
Herbs, garlic or spices. It is no longer just salt. Spices go in separately, as the recipe says.

Weigh it, whatever it is

A cup of salt can weigh anywhere from 230 to 335 g depending on the salt¹⁶. Kosher salt, for example, is around 245 g per cup¹⁷. Spoons work the same way: a tablespoon of flake salt holds far less salt than a tablespoon of fine salt.

That is why the guides ask you to weigh it¹⁸ and accept flake salt only if it is weighed and swapped weight for weight¹⁹. In a ferment salt isn't just seasoning: it controls the fermentation and has to be measured carefully²⁰. 2.5% is 2.5% with any pure salt, as long as it goes on the scale. That is why Fervida always gives salt in grams.

If something looks off

The wrong salt leaves clues. But some of them look like normal fermentation:

You see	It may be the salt	It is also normal if
Cloudy brine	Anti-caking agents¹⁰	It is the first week: brine clouds up and clears by the fourth²¹
White sediment at the bottom	Anti-caking agents¹¹	Fermenting bacteria made it²²
Dark pickles	Iodine⁹
Bitter taste	Potassium chloride¹⁵

None of these alone means the jar has spoiled. Mold, a rotten smell or a slimy texture do: Reading your jar explains them.

If you want less sodium

Don't switch salts or cut back. Low-sodium substitutes don't work for fermenting¹², salt can't be left out of a ferment²³ and reducing it is not safe²⁴. If you want less salt on the plate, rinse the ferment before serving or use it as a condiment. Salt and diet covers this in detail.

Where every number comes from

Every number in the text leads to its figure: the exact sentence from the official guide it comes from, in its own language.

1

Salt with no additives

“The salt used in fermentation should contain no additives.”

University of Illinois Extension · Fermentation handout (2020) · read on October 20, 2026
2

No iodine: it can interfere with fermentation

“Salt should be iodine-free, as iodine can interfere with fermentation.”

University of Minnesota Extension · Preserving food at home: Fermentation (reviewed 2026) · read on October 25, 2026
3

Canning or pickling salt is recommended: no impurities, even grain

“Canning or pickling salt is recommended since it contains no impurities and has a consistent granular size and weight.”

University of Illinois Extension · Fermentation handout (2020) · read on October 20, 2026
4

Pickling or coarse salt, non-iodized

“Choice of salt is important, use a pickling or coarse salt that is non-iodized.”

BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
5

Pure granulated salt, sold as pickling or canning salt

“Pure granulated salt, sold as “Pickling” or “Canning” salt should be used.”

UC Master Food Preservers, Mariposa County (UC ANR) · Pickling versus Fermenting around the World: Key Ingredients (Mariposa MFP, 12-nov-2022) · read on October 26, 2026
6

Kosher salt works too: it has no anti-caking agents

“Kosher salt, which is salt manufactured to conform to Jewish dietary laws, may also be used. These salts do not contain anti-caking agents.”

UC Master Food Preservers, Mariposa County (UC ANR) · Pickling versus Fermenting around the World: Key Ingredients (Mariposa MFP, 12-nov-2022) · read on October 26, 2026
7

Sea salt can be used by weight, but its impurities vary and can affect the result

“Similarly, sea salt can be substituted on a weight-basis in pickle recipes. However, the type and quantity of impurities varies considerably, and may affect product quality.”

UC Master Food Preservers, Mariposa County (UC ANR) · Pickling versus Fermenting around the World: Key Ingredients (Mariposa MFP, 12-nov-2022) · read on October 26, 2026
8

Flake salt isn't recommended: its density varies

“Since flake salt varies in density, it is not recommended for making pickled and fermented foods.”

National Center for Home Food Preservation (USDA, University of Georgia) · General Information on Fermenting · read on October 26, 2026
9

Iodized table salt has iodine and anti-caking agents: they cloud the brine and darken pickles

“Iodized table salt contains iodine and anti-caking materials that may interfere with fermentation. Anti-caking ingredients make the brine cloudy and iodine may darken pickles.”

UC Master Food Preservers, Mariposa County (UC ANR) · Pickling versus Fermenting around the World: Key Ingredients (Mariposa MFP, 12-nov-2022) · read on October 26, 2026
10

Anti-caking agents can cloud the brine

“Noncaking material added to other salts may make the brine cloudy.”

National Center for Home Food Preservation (USDA, University of Georgia) · General Information on Fermenting · read on October 26, 2026
11

White sediment can come from salt with an anti-caking agent

“Salt contains an anti-caking agent or other additives.”

National Center for Home Food Preservation (USDA, University of Georgia) · Causes and Possible Solutions for Problems with Fermented Pickles · read on October 26, 2026
12

Low-sodium substitutes don't work for fermenting

“Reduced sodium salt substitutes should not be used in making fermented pickles or sauerkraut, because the specific properties of sodium chloride are required to achieve the desired fermentation.”

UC Master Food Preservers, Mariposa County (UC ANR) · Pickling versus Fermenting around the World: Key Ingredients (Mariposa MFP, 12-nov-2022) · read on October 26, 2026
13

For businesses, BCCDC advises against iodized, sea and specialty salts

“Iodized salts, sea salts and other speciality salts are not recommended as they may contain heavy metals, anti-caking agents or other agents that interfere with fermentation.”

BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
14

The wrong salt can discolor the brine and mask spoilage

“Problems linked to non food-grade salts include discolouration of the fermentation brine, and masking of spoilage.”

BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
15

The potassium chloride in substitutes tastes bitter

“Potassium chloride, the ingredient in most of these, causes bitterness.”

National Center for Home Food Preservation (USDA, University of Georgia) · Causes and Possible Solutions for Problems with Fermented Pickles · read on October 26, 2026
16

A cup of salt weighs 230 to 335 g depending on the salt

“Salt varies from 230 g to 335 g per US cup measured.”

UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026
17

A cup of kosher salt weighs about 245 g

“Kosher is more like 245 g / cup.”

UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026
18

Weighing salt is best

“It is best to weigh salt for accuracy.”

University of Illinois Extension · Fermentation handout (2020) · read on October 20, 2026
19

Flakes only work if weighed and swapped weight for weight

“Because the density of flake salt varies, its use is not recommended in making pickles and sauerkraut – unless you are able to weigh the flake salt and substitute it in recipes on a weight-for-weight basis.”

UC Master Food Preservers, Mariposa County (UC ANR) · Pickling versus Fermenting around the World: Key Ingredients (Mariposa MFP, 12-nov-2022) · read on October 26, 2026
20

In a ferment, salt must be measured carefully

“In fermented pickles, salt plays an important role in controlling fermentation, and must be carefully measured.”

UC Master Food Preservers, Mariposa County (UC ANR) · Pickling versus Fermenting around the World: Key Ingredients (Mariposa MFP, 12-nov-2022) · read on October 26, 2026
21

Brine turns cloudy in the first week and clears by the fourth

“The brine becomes cloudy as the fermentation proceeds (week 1), then clears (week 4).”

BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
22

Fermenting bacteria also make white sediment

“White sediment in jar. 1. Bacteria cause this during fermentation.”

National Center for Home Food Preservation (USDA, University of Georgia) · Causes and Possible Solutions for Problems with Fermented Pickles · read on October 26, 2026
23

Salt can't be left out of a ferment

“Salt can be omitted in fresh-pack pickle recipes, but cannot be omitted when making fermented (brined) pickles or sauerkraut.”

UC Master Food Preservers, Mariposa County (UC ANR) · Pickling versus Fermenting around the World: Key Ingredients (Mariposa MFP, 12-nov-2022) · read on October 26, 2026
24

Reducing salt is not safe

“It is unsafe to reduce salt in lactofermented vegetables.”

UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026

Keep reading

Salt: how much and why Dry salting or brine Water and chlorine Reading your jar: color, smell and bubbles Salt and diet Kitchen scales