For many fermentation recipes, especially those using grains and vegetables, salt is a critical ingredient.  Salt, when used in the right proportions, creates an environment within which we are able to better control the growth of microorganisms and have a happier ferment.

Some fermentations such as yoghurt and other beverages which don’t use salt require a strenuously sterile environment if everything is to come out well.  While the first defense is always cleanliness (I always scrub my hands thoroughly, wash the fermenting vessel well and clean my work surface prior to getting to work), salt gives a fermentation project extra level of protection, creating an environment where harmful microorganisms have a difficult time thriving while not hindering the growth of the bacteria and or yeast which is beneficial to the fermentation and your health.

How much salt do I use and how do I use it when I am fermenting?

• Dry salting – tossing your vegetables with salt and allowing the salt to draw liquid from the vegetables.  For this, the typical amount of salt to be used would be approximately 1 TBS for every 1 1/2 lbs of vegetables. You can experiment with using less as I do sometimes. The salt effectively stabilizes the environment while the bacteria involved in the fermentation take hold, somless salt means a little more risk of spoilage. This technique is commonly used for sauerkraut.
• Pre-brining – mixing a brine by dissolving salt in water and then soaking the vegetables in the brine.  This is followed by draining off the brine and then compressing the vegetables to encourage further liquid to escape the vegetables and cover the vegetables for the fermenting process.  A stronger brine of 4 TBS salt for 4 cups of water is good for this.  I use this commony for kimchi.
• Brining – mixing a brine of salt and water and submerging the vegetables within that brine, commonly used for making pickles. 2% – 5% brine by weight is most common.  See table in Making Your Brine section below.  I use this technique for pickling vegetables that don’t lend themselves to being compressed (asparagus, green beans, whole jalapenos, etc.)
• Bouyancy Brining – that’s my term, but basically it’s a very strong brine (something that if you swam in it, you’d have a hard time not being bouyant).  This can work well when you need to pickle and preserve something without needing to refrigerate it afterwards, as in making actual pickles.  Once pickled and when ready to eat, you can rinse the vegetables several times to remove some of the salt so as to make the dish/pickle more palatable.
• Added Salt – sometimes, when fermenting salsa or something that is more akin to a paste (mustard, horseradish, ketchup, etc.) I’ll simply add some salt to the mixture to help keep the environment more stable.

Please note regarding the use of kosher salt – when measurements in Tablespoons are used in this article, that the salt used is a normal grained sea salt or table salt. For courser grained salts such as kosher salt, there is less salt by volume since there is more room for air between the grains. This of course depends on the size of the grain, but a good rule of thumb is that if you are using kosher salt, use 25% more by volume.

How much salt should I use for a brine?
When mixing a brine within which you will submerge your fermentables, it is common to mix to a salinity level between 1.5% and 5% with the sweet spot being in the 2-3% range. This percentage is actually a proportion by weight, so if you divide the weight of your salt by the weight of your water used, you will come up with the percentage.  For example, a brine typically will have approximately 2.5 TBS salt to 4 cups of water, in my kitchen, those weights are:

• 4 cups water – 960 grams – 32 oz
• 1 TBS sea salt – 19 grams – .67ounce

Making your brine
to mix 4 cups of brine to various salinity percentages, dissolve the following amounts of salt into 4 cups of water:

2% brine – 1 TBS sea salt
3% brine – 1.5 TBS sea salt
4% brine – 2 TBS sea salt
5% brine – 2.5 TBS sea salt

i have a scale in my kitchen which I would recommend to you which comes in quite handy for measuring salt proportion by weight. This scale has a “Baker’s math” function. You simply weigh your water and press the % key. Remove the water and then place salt on the scale and it will display as a % of the original water weight. Keep adding salt until you get to the targeted percentage.

evaporated sea water forms into salt crystals on the rocks near my home

Which type of salt should I use for fermenting?

• I recommend using sea salt where possible as it is a naturally formed salt and often contains various nutrients including trace amounts of magnesium, potassium, and calcium.  Living on the California coast, I sometimes go out and collect some of my own sea salt off the rocks – (see image to right and large image above).  Some of the best salts for mineral values are Himalayan sea salt (still boggles me how the Himalayas can have sea salt, but that’s another topic entirely) and the sea salts found on Islands off the Atlantic coast of France.
• Pickling salt is fine as well as is kosher salt.
• I don’t recommend using standard iodized table salt as it contains iodine which can have a negative effect on the bacteria that ferment the food. Also, as part of it’s processing, it is stripped of its trace mineral content and is diluted with an anti-caking agent.

Please feel free to share any additional thoughts or information here.  Happy fermenting!